From bounce-tacgps-6754@lists.tapr.org Thu Aug 2 21:31:18 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id VAA07866 for ; Thu, 2 Aug 2001 21:31:13 -0500 (CDT) Date: Mon, 23 Jul 2001 14:14:16 -0400 From: John Ackermann To: "TAPR Special Interest Group" Subject: [tacgps] Re: Slightly OT: Playing with VLF Frequency Measurement Message-ID: In-Reply-To: References: List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Software: Lyris Server version 3.0 List-Subscribe: List-Subscribe: List-Owner: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk X-Mailer: Mulberry/2.1.0a6 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline --On Monday, July 23, 2001 2:05 PM -0400 John Ackermann wrote: > Those are neat looking pictures, and great data! I hope mine works as > well... Sorry, that wasn't meant for the list. John --- You are currently subscribed to tacgps as: JDEGOOD@SARNOFF.COM To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 2 21:31:36 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id VAA07878 for ; Thu, 2 Aug 2001 21:31:35 -0500 (CDT) Date: Mon, 23 Jul 2001 14:05:25 -0400 From: John Ackermann To: "TAPR Special Interest Group" Subject: [tacgps] Re: Slightly OT: Playing with VLF Frequency Measurement Message-ID: In-Reply-To: References: List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Software: Lyris Server version 3.0 List-Subscribe: List-Subscribe: List-Owner: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk X-Mailer: Mulberry/2.1.0a6 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Those are neat looking pictures, and great data! I hope mine works as well... My 2.5 had a power supply and was mounted in a similar 2-holed rack panel when I got it, but the batteries had leaked and the thing was pretty much toast. I got a local shop to make a new panel for me, with the standard mounted in the center and a vast bunch of BNC bulkhead connectors arrayed on either side; it became the main patch panel for all my measurement stuff. Mine, by the way, is a 2.5 (no letter suffix) version, so must be quite a bit older. I have a photocopy of the original manual which shows the specs and I think a 1962 date. I'm probably going to be shutting my stuff down for the move this coming weekend, and will pack the Sulzer up and send it to you then. By that time, I will have better than a week's worth of WWVB data from the present run (assuming nothing crashes in the meantime...) John --On Monday, July 23, 2001 12:40 AM -0700 Tom Van Baak wrote: > Have a look at these two Sulzer 2.5C oscillators which are > stable in the short-term to 2E-13 and 5E-13, respectively. > > http://www.leapsecond.com/museum/sul25-1/ > > http://www.leapsecond.com/museum/sul25-2/ > > /tvb > > > --- > You are currently subscribed to tacgps as: JRA@FEBO.COM > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > > > --- You are currently subscribed to tacgps as: JDEGOOD@SARNOFF.COM To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 10 13:54:58 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id NAA11854 for ; Fri, 10 Aug 2001 13:54:54 -0500 (CDT) Message-ID: Date: Fri, 10 Aug 2001 14:53:29 -0400 From: Bob Smith Organization: Smith Machine Works X-Sender: "Bob Smith" <@mail> (Unverified) X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B742DA9.80B7EEC8@home.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Dear Dr. Clark and subscribers -- I am conducting experiments with my M12 from Synergy and TAC32 with an immediate goal of understanding its performance characteristics in my environment. My longterm goal is precision timing. It is becomming obvious that I need to improve my antenna situation, which is pretty poor at the moment, yet I seem to be getting usable results. I recall references to a "choke ring" antenna that you designed and, possibly, a helix type (that was based on a drink cup???). I am a skilled machinest and would appreciate any web references to guide me in construction of such a beast. Sincerely, Bob Smith, WA4YPV -- --------- Avoid computer viruses -- Practice safe hex ------------- * * Specializing in small, cost effective embedded control systems * * Robert L. (Bob) Smith Smith Machine Works, Inc. internet bobsmith5@home.com 9900 Lumlay Road landline 804/745-1065 Richmond, Virginia 23236+1004 --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 10 13:57:27 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id NAA11946 for ; Fri, 10 Aug 2001 13:57:25 -0500 (CDT) Message-ID: Date: Fri, 10 Aug 2001 14:55:59 -0400 From: Bob Smith Organization: Smith Machine Works X-Sender: "Bob Smith" <@mail> (Unverified) X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Homebrewed atomic standards??? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B742E3F.DD1B8080@home.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hello all -- Anybody ever given any serious thought to a home brewed hydrogen / cesium / rubidium standard??? Just how insane have I become?? 73, de bob, wa4ypv > > --- > You are currently subscribed to tacgps as: bobsmith5@home.com > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org -- --------- Avoid computer viruses -- Practice safe hex ------------- * * Specializing in small, cost effective embedded control systems * * Robert L. (Bob) Smith Smith Machine Works, Inc. internet bobsmith5@home.com 9900 Lumlay Road landline 804/745-1065 Richmond, Virginia 23236+1004 --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 10 14:35:17 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id OAA14998 for ; Fri, 10 Aug 2001 14:35:12 -0500 (CDT) Mime-Version: 1.0 X-Sender: j.m.franke@express.larc.nasa.gov Message-Id: Date: Fri, 10 Aug 2001 15:34:20 -0400 To: "TAPR Special Interest Group" From: John Franke Subject: [tacgps] Re: Homebrewed atomic standards??? Content-Type: text/plain; charset="us-ascii" ; format="flowed" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Cesium and hydrogen are flowing systems and require continuous pumping or replacement systems. Rubidium has always appealed to me because it is uses sealed off gas cells. I was considering going back a little further to an ammonia absorption cell system. It is not as accurate (~5 x 10-8) as a rubidium, but the gases are more easily obtained, a gas discharge optical source is not needed, and initially I would not be concerned with buffer gases. The operating frequency, 23.8701 GHz, is easily reached with affordable devices. After all, the saturation drive level is around 1.8 milliwatts, depending on cell size and pressure. The absorption is about 13% per 12 feet at a cell (waveguide) pressure of 10 microns. Anyway, that is the way I have been thinking of going. John WA4WDL >Hello all -- > >Anybody ever given any serious thought to a home brewed hydrogen / >cesium / rubidium standard??? > >Just how insane have I become?? > > 73, de bob, wa4ypv > > > > > > --- > > You are currently subscribed to tacgps as: bobsmith5@home.com > > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > >-- > >--------- Avoid computer viruses -- Practice safe hex ------------- > * * Specializing in small, cost effective embedded control systems * * >Robert L. (Bob) Smith Smith Machine Works, Inc. >internet bobsmith5@home.com 9900 Lumlay Road >landline 804/745-1065 Richmond, Virginia 23236+1004 > >--- >You are currently subscribed to tacgps as: J.M.FRANKE@LARC.NASA.GOV >To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 10 16:19:49 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id QAA27194 for ; Fri, 10 Aug 2001 16:19:46 -0500 (CDT) Message-ID: From: jim_johnson@agilent.com To: "TAPR Special Interest Group" Subject: [tacgps] RE: Homebrewed atomic standards??? Date: Fri, 10 Aug 2001 14:18:25 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Bob, Wow, are you ever ambitious! My first question is, why would you want to do such a thing? You can get VERY good, nearly cesium-like performance these days (no more SA) by disciplining a good quartz oscillator with a GPS controller designed by Brooks Shera. In fact, a colleague of mine and I have done just that and we now have clocks that perform as well (sometimes better) than the HP 58503A, which sells for around $6,000. Our cost has been somewhere in the neighborhood of (I'm guessing at this) $300 plus the cost of the quartz oscillator and the GPS receiver. We were fortunate to have oscillators and GPS receivers lying around so we used what we had. As far as homebrewing atomic standards, the electronics could certainly be built as a hobby project (not for the faint of heart, however) but a cesium beam tube? Not a chance. For rubidium you need glassware (glass cell with Rb in it and a glass lamp with Rb) and a microwave cavity. Both the cesium beam tube and the lamp in the Rb have finite lifetimes, as opposed to quartz which should last forever. Putting it into perspective, you might have better luck homebrewing a jet aircraft than you would a cesium beam frequency standard - but I'm impressed with your level of ambition. Good luck! Jim Johnson Precision Instrumentation Agilent Laboratories Palo Alto, CA > -----Original Message----- > From: Bob Smith [mailto:bobsmith5@home.com] > Sent: Friday, August 10, 2001 11:56 AM > To: TAPR Special Interest Group > Subject: [tacgps] Homebrewed atomic standards??? > > > Hello all -- > > Anybody ever given any serious thought to a home brewed hydrogen / > cesium / rubidium standard??? > > Just how insane have I become?? > > 73, de bob, wa4ypv --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 10 23:04:32 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id XAA24870 for ; Fri, 10 Aug 2001 23:04:27 -0500 (CDT) Message-ID: Date: Fri, 10 Aug 2001 21:03:20 -0700 From: Dan Hinz X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B74AE88.371E8083@ieee.org> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Try this page has several links: http://www.unavco.ucar.edu/dev_test/antennas/pcv.html 73, Dan - W6LSN Bob Smith wrote: > > Dear Dr. Clark and subscribers -- > > I am conducting experiments with my M12 from Synergy and TAC32 with an > immediate goal of understanding its performance characteristics in my > environment. My longterm goal is precision timing. > > It is becomming obvious that I need to improve my antenna situation, > which is pretty poor at the moment, yet I seem to be getting usable > results. I recall references to a "choke ring" antenna that you > designed and, possibly, a helix type (that was based on a drink cup???). > > I am a skilled machinest and would appreciate any web references to > guide me in construction of such a beast. > > Sincerely, Bob Smith, WA4YPV > > > > -- > > --------- Avoid computer viruses -- Practice safe hex ------------- > * * Specializing in small, cost effective embedded control systems * * > Robert L. (Bob) Smith Smith Machine Works, Inc. > internet bobsmith5@home.com 9900 Lumlay Road > landline 804/745-1065 Richmond, Virginia 23236+1004 > > --- > You are currently subscribed to tacgps as: DAN.HINZ@IEEE.ORG > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sat Aug 11 09:42:50 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id JAA08395 for ; Sat, 11 Aug 2001 09:42:49 -0500 (CDT) Message-ID: Date: Sat, 11 Aug 2001 10:42:18 -0400 From: Bob Smith Organization: Smith Machine Works X-Sender: "Bob Smith" <@mail> (Unverified) X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B75444A.3947C1D2@home.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Many thanks to Dan for these useful links!! They have produced much useful information on the machining problem. As always, a project such as this leads to additional questions: 1. The classic choke ring seems to run about 16" in diameter. My intent was to hog one out of a billet of aluminum or brass but, this is simply too big to swing on my fine little 9" Southbend toolroom lathe. Does anyone have a feel for the impact of reducing the design to 8"-9" overall. Certainly there would be some loss in multipath rejection, but I am not on a millimeter geodesic survey, I just want a good antenna for recision timing use in my ham shack. 2. The key, driving element of the choke ring seems to be the "Dorne & Margolin C146-10 dipole antenna element". This seems to be a 10 element dipole array of some type. Anybody know of any information resources for this? A net search turned up nothing but advertisement blurbs for choke ring antennas that used the D & M element. Are there simpler ways to couple the choke ring ground plane to the feed line? Perhaps a simple vertical probe or a two element dipole? Many thanks es 73, de Bob WA4YPV / TAPR supporter Dan Hinz wrote: > > Try this page has several links: > > http://www.unavco.ucar.edu/dev_test/antennas/pcv.html > > 73, > Dan - W6LSN -- --------- Avoid computer viruses -- Practice safe hex ------------- * * Specializing in small, cost effective embedded control systems * * Robert L. (Bob) Smith Smith Machine Works, Inc. internet bobsmith5@home.com 9900 Lumlay Road landline 804/745-1065 Richmond, Virginia 23236+1004 --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sat Aug 11 10:27:02 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id KAA10228 for ; Sat, 11 Aug 2001 10:26:55 -0500 (CDT) Message-ID: From: "Brooks Shera" To: "TAPR Special Interest Group" References: Subject: [tacgps] Re: GPS Antennas Date: Sat, 11 Aug 2001 09:25:58 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <009501c12279$ec972480$6400a8c0@brooksnotebook> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi I suggest that if your interest is in timing you don't need to bother putting a choke ring under your gps antenna. The timing accuracy of a receiver is not very much affected by its exact location. For example, in position-hold mode the position can be incorrect by several meters with no appreciable effect on the timing accuracy. Even for surveying, the choke ring is only important at the mm accuracy level in my experience. Accuracy at the cm level is readily obtained using simple, bare mag-mount patch antennas such as the Motorola Ant-97 (see www.rt66.com/~shera for some surveying results with simple equipment). Perhaps the best thing you can do is put your antenna in a location with a good view of the sky. Brooks >From: "Bob Smith" Many thanks to Dan for these useful links!! > > They have produced much useful information on the machining problem. As > always, a project such as this leads to additional questions: > > 1. The classic choke ring seems to run about 16" in diameter. My > intent was to hog one out of a billet of aluminum or brass but, this is > simply too big to swing on my fine little 9" Southbend toolroom lathe. > Does anyone have a feel for the impact of reducing the design to 8"-9" > overall. Certainly there would be some loss in multipath rejection, but > I am not on a millimeter geodesic survey, I just want a good antenna for > recision timing use in my ham shack. > > 2. The key, driving element of the choke ring seems to be the "Dorne & > Margolin C146-10 dipole antenna element". This seems to be a 10 element > dipole array of some type. Anybody know of any information resources > for this? A net search turned up nothing but advertisement blurbs for > choke ring antennas that used the D & M element. Are there simpler > ways to couple the choke ring ground plane to the feed line? Perhaps a > simple vertical probe or a two element dipole? > > Many thanks es 73, de Bob WA4YPV / TAPR supporter > > > Dan Hinz wrote: > > > > Try this page has several links: > > > > http://www.unavco.ucar.edu/dev_test/antennas/pcv.html > > > > 73, > > Dan - W6LSN > > -- > > --------- Avoid computer viruses -- Practice safe hex ------------- > * * Specializing in small, cost effective embedded control systems * * > Robert L. (Bob) Smith Smith Machine Works, Inc. > internet bobsmith5@home.com 9900 Lumlay Road > landline 804/745-1065 Richmond, Virginia 23236+1004 > > --- > You are currently subscribed to tacgps as: EBS@LANL.GOV > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sat Aug 11 10:45:29 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id KAA10769 for ; Sat, 11 Aug 2001 10:45:23 -0500 (CDT) Message-ID: Date: Sat, 11 Aug 2001 11:44:15 -0400 From: Bob Smith Organization: Smith Machine Works X-Sender: "Bob Smith" <@mail> (Unverified) X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] RE: Homebrewed atomic standards??? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B7552CF.A5E3C2C0@home.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Jim -- Thanks for the reality check. In fact, I have a fair oscillator that I am currently hand tracking to GPS using a home brew counter timer chain that will generate 1 PPS pulses at thumbwheel settable 1 mS intervals and the 1 PPS from my M12 GPS as a scope trigger. The oscillator is 40+ years old and is getting a little (very) tired. Thus I lust after a *really* stable oscillator. I'll reconsider the TOC solution. I've got the QST artical around here somewhere. So thanks, and back to my real homebrew! 73, de bob jim_johnson@agilent.com wrote: > > Hi Bob, > > Wow, are you ever ambitious! My first question is, > why would you want to do such a thing? You can get VERY > good, nearly cesium-like performance these days (no more SA) > by disciplining a good quartz oscillator with a GPS controller > designed by Brooks Shera. In fact, a colleague of mine and > I have done just that and we now have clocks that perform > as well (sometimes better) than the HP 58503A, which sells > for around $6,000. Our cost has been somewhere in the > neighborhood of (I'm guessing at this) $300 plus the > cost of the quartz oscillator and the GPS receiver. We > were fortunate to have oscillators and GPS receivers lying > around so we used what we had. > > As far as homebrewing atomic standards, the electronics > could certainly be built as a hobby project (not for the > faint of heart, however) but a cesium beam tube? Not a > chance. For rubidium you need glassware (glass cell with > Rb in it and a glass lamp with Rb) and a microwave cavity. > Both the cesium beam tube and the lamp in the Rb have > finite lifetimes, as opposed to quartz which should last > forever. > > Putting it into perspective, you might have better > luck homebrewing a jet aircraft than you would a cesium > beam frequency standard - but I'm impressed with your level > of ambition. Good luck! > > Jim Johnson > Precision Instrumentation > Agilent Laboratories > Palo Alto, CA > > > -----Original Message----- > > From: Bob Smith [mailto:bobsmith5@home.com] > > Sent: Friday, August 10, 2001 11:56 AM > > To: TAPR Special Interest Group > > Subject: [tacgps] Homebrewed atomic standards??? > > > > > > Hello all -- > > > > Anybody ever given any serious thought to a home brewed hydrogen / > > cesium / rubidium standard??? > > > > Just how insane have I become?? > > > > 73, de bob, wa4ypv > > --- > You are currently subscribed to tacgps as: bobsmith5@home.com > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org -- --------- Avoid computer viruses -- Practice safe hex ------------- * * Specializing in small, cost effective embedded control systems * * Robert L. (Bob) Smith Smith Machine Works, Inc. internet bobsmith5@home.com 9900 Lumlay Road landline 804/745-1065 Richmond, Virginia 23236+1004 --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sat Aug 11 18:15:42 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id SAA14696 for ; Sat, 11 Aug 2001 18:15:39 -0500 (CDT) Sender: bounce-tacgps-6754@lists.tapr.org Message-ID: Date: Sat, 11 Aug 2001 18:16:14 -0500 From: Gerry Creager N5JXS Reply-To: "TAPR Special Interest Group" Organization: Da House X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: <3B75BCBE.DEDFD637@cs.tamu.edu> Precedence: bulk Maybe Lyris won't choke because this is too long... Overall, I agree strongly with Brooks. (Of course, having spent a lot of time doing some similar work on surveying accuracy may have something to do with it...). To expand further, however, on timing antennas, it's much more important to ask your receiver to look high in the sky (minimize tropo/iono impact, and to reduce, where possible, multipath interference. I am truly fascinated by the Novatel spiral chokering design, and by the Javad "dual-depth" chokering, which utilizes tuned cavities to sink errant signal to ground. The choke ring is designed to mitigate multipath and ground reflected radiation. It acts, effectively by increasing the Q of the antenna. I've argued, conversely, that what it does is introduce a knife-edge diffraction component in the near-field. I suspect the truth lies in a synthesis of the two, more'n likely with more weight going to antenna Q. Personal experience, however, suggests that the right answer is to place the antenna in an area where multipath is minimized rather than depending on a chokering to fix your problems. When worrying about survey accuracies, the important aspects of reproducibility mandate use of an antenna with either well determined phase center characteristics, or that you adequately ascertain these characteristics empirically. I believe a little more strongly than Brooks that either a chokering mount or a large groundplane is beneficial here... or an antenna nestled in charcoal, perhaps. In general, I prefer patch antennas to either discrete element or helical antennas for survey GPS work, based on my experience. Some day, when I can get funding for it, I'll set up a proper antenna test range for GPS antenna work, and verify this. 73, gerry -- Brooks Shera wrote: > > Hi > I suggest that if your interest is in timing you don't need to bother > putting a choke ring under your gps antenna. The timing accuracy of a > receiver is not very much affected by its exact location. For example, in > position-hold mode the position can be incorrect by several meters with no > appreciable effect on the timing accuracy. Even for surveying, the choke > ring is only important at the mm accuracy level in my experience. Accuracy > at the cm level is readily obtained using simple, bare mag-mount patch > antennas such as the Motorola Ant-97 (see www.rt66.com/~shera for some > surveying results with simple equipment). > > Perhaps the best thing you can do is put your antenna in a location with a > good view of the sky. > > >From: "Bob Smith" > Many thanks to Dan for these useful links!! > > > > They have produced much useful information on the machining problem. As > > always, a project such as this leads to additional questions: > > > > 1. The classic choke ring seems to run about 16" in diameter. My > > intent was to hog one out of a billet of aluminum or brass but, this is > > simply too big to swing on my fine little 9" Southbend toolroom lathe. > > Does anyone have a feel for the impact of reducing the design to 8"-9" > > overall. Certainly there would be some loss in multipath rejection, but > > I am not on a millimeter geodesic survey, I just want a good antenna for > > recision timing use in my ham shack. > > > > 2. The key, driving element of the choke ring seems to be the "Dorne & > > Margolin C146-10 dipole antenna element". This seems to be a 10 element > > dipole array of some type. Anybody know of any information resources > > for this? A net search turned up nothing but advertisement blurbs for > > choke ring antennas that used the D & M element. Are there simpler > > ways to couple the choke ring ground plane to the feed line? Perhaps a > > simple vertical probe or a two element dipole? > > > > Dan Hinz wrote: > > > > > > Try this page has several links: > > > > > > http://www.unavco.ucar.edu/dev_test/antennas/pcv.html -- Gerry Creager -- gerry@cs.tamu.edu Network Engineering Academy for Advanced Telecommunications and Learning Technologies Texas A&M University 979.458.4020 (Phone) -- 979.847.8578 (Fax) --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sun Aug 12 10:45:56 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id KAA21023 for ; Sun, 12 Aug 2001 10:45:55 -0500 (CDT) Message-ID: Date: Sun, 12 Aug 2001 08:45:08 -0700 From: Dan Hinz X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] RE: Homebrewed atomic standards??? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B76A484.120534F8@ieee.org> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Bob You mentioned that your oscillator was tired. If you need a source for them, you can try either of the links below. I purchased mine from the first one shortly after Brooks' article first appeared. I checked today and the "test equipment" link is dead, might want to send an e-mail to Gary- N6ZD the owner. He was very helpful with several questions that I had. The second link is also mentioned in Brooks' article. Might consider e-bay too. http://tech-services.com/consult.htm http://www.lehmanscientific.com/ Good Luck & 73 Dan - W6LSN --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sun Aug 12 11:39:12 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id LAA24791 for ; Sun, 12 Aug 2001 11:39:09 -0500 (CDT) Message-ID: Date: Sun, 12 Aug 2001 09:40:47 -0700 From: "Eric G. Lemmon" X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B76B18F.1258575A@impulse.net> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Bob, I am not a GPS antenna expert, but I have experimented with a half-dozen or so antennas on an Ashtech centimeter-grade (carrier phase) GPS receiver and a Motorola Oncore VP timing receiver. When you are trying to establish the L1 carrier phase, any multipath signals can be extremely disruptive, and that is why choke-ring and other "low multipath" antennas were developed. However, the fancy machine work on the fins is only part of the high cost of such antennas. In order to establish a GPS position at the centimeter level (not to mention the millimeter level), the antenna must have a phase center that is exactly on the physical axis. This coincidence must be uniform at all points of the compass, from just above the horizon to the zenith. This is a tall order, and it involves not just precision design and manufacturing, but also some intensive calibration and alignment. One experiment I performed to verify this statement was to center a fairly inexpensive patch antenna on a level ground plane disk, with a clear view of the sky in all directions. I used my Ashtech receiver to record RINEX data in a number of two-hour sessions, rotating the disk on its axis a known angle between sessions. After post-processing the data, I noted a "slop" of nearly a meter in the position solution. I then repeated the test, using my Ashtech low-multipath antenna on the same mount, and found the position error to be less than 3 cm. Now, I know that this experiment will not stand up under scientific scrutiny, simply because a robust test requires several days, at various times of the day, and much longer occupations. Nevertheless, I know that precision positioning requires precision antennas. I am convinced that precision timing, which is sensitive to carrier phase, will also benefit from antennas which have a uniform phase response and freedom from multipath reception. A choke-ring antenna may be extreme overkill. I'd opt for a GPS antenna designed for timing reception. 73, Eric Lemmon WB6FLY > >Bob Smith wrote: I am conducting experiments with my M12 from Synergy and > TAC32 with an immediate goal of understanding its performance > characteristics in my environment. My longterm goal is precision timing. > It is becomming obvious that I need to improve my antenna situation, which > is pretty poor at the moment>>> --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sun Aug 12 13:07:54 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id NAA02863 for ; Sun, 12 Aug 2001 13:07:52 -0500 (CDT) Sender: bounce-tacgps-6754@lists.tapr.org Message-ID: Date: Sun, 12 Aug 2001 13:07:54 -0500 From: Gerry Creager N5JXS Reply-To: "TAPR Special Interest Group" Organization: Da House X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: GPS Antennas References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: <3B76C5FA.978CD787@cs.tamu.edu> Precedence: bulk In fact, the experiments you performed, if well documented, would stand up under scrutiny. One thing I'd suggest... and National Geodetic Survey confirms: 4-hour occupations for geodetic work are necessary. I've published on this, and will try to get that manuscript up on http://page4.cs.tamu.edu/page4/ maybe next week ("How Long Must We Wait?"). I find an error of slop a bit larger than I'd have expecte or what I've seen in some of MY ad hoc experiments, but not inexplicable. And, your point that the phase center of the L1 element for the chokering-augmented antenna must be zero'd is completely accurate. The L2 phase center must be well documented, as well. gerry -- "Eric G. Lemmon" wrote: > > Bob, > > I am not a GPS antenna expert, but I have experimented with a half-dozen or so > antennas on an Ashtech centimeter-grade (carrier phase) GPS receiver and a > Motorola Oncore VP timing receiver. When you are trying to establish the L1 > carrier phase, any multipath signals can be extremely disruptive, and that is > why choke-ring and other "low multipath" antennas were developed. However, > the fancy machine work on the fins is only part of the high cost of such > antennas. In order to establish a GPS position at the centimeter level (not > to mention the millimeter level), the antenna must have a phase center that is > exactly on the physical axis. This coincidence must be uniform at all points > of the compass, from just above the horizon to the zenith. This is a tall > order, and it involves not just precision design and manufacturing, but also > some intensive calibration and alignment. > > One experiment I performed to verify this statement was to center a fairly > inexpensive patch antenna on a level ground plane disk, with a clear view of > the sky in all directions. I used my Ashtech receiver to record RINEX data in > a number of two-hour sessions, rotating the disk on its axis a known angle > between sessions. After post-processing the data, I noted a "slop" of nearly > a meter in the position solution. I then repeated the test, using my Ashtech > low-multipath antenna on the same mount, and found the position error to be > less than 3 cm. > > Now, I know that this experiment will not stand up under scientific scrutiny, > simply because a robust test requires several days, at various times of the > day, and much longer occupations. Nevertheless, I know that precision > positioning requires precision antennas. I am convinced that precision > timing, which is sensitive to carrier phase, will also benefit from antennas > which have a uniform phase response and freedom from multipath reception. A > choke-ring antenna may be extreme overkill. I'd opt for a GPS antenna > designed for timing reception. -- Gerry Creager -- gerry@cs.tamu.edu Network Engineering Academy for Advanced Telecommunications and Learning Technologies Texas A&M University 979.458.4020 (Phone) -- 979.847.8578 (Fax) --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Sun Aug 12 14:30:00 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id OAA07719 for ; Sun, 12 Aug 2001 14:29:55 -0500 (CDT) Message-ID: From: "Brooks Shera" To: "TAPR Special Interest Group" References: Subject: [tacgps] Re: GPS Antennas Date: Sun, 12 Aug 2001 13:29:19 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <005e01c12365$15b77c20$6400a8c0@brooksnotebook> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk I agree with Gerry, position differences of a meter are rather large to be caused by carrier phase multipath. Only I would say, WAY too large. The most serious effect of multipath reflections is to shift the true phase by 90 degrees (a quarter of a cycle, which is 5 cm for a wavelength of 20 cm). This topic is discussed at some length in the excellent book "GPS: Theory and Practice" by Hoffmann-Wellenhof, et al. The size of the differences you report suggest to me that your position measurements might be based on code rather than carrier data, since the larger effective wavelength of the code phase makes multipath a much larger effect. In fact, I have used this difference (over a short baseline) to estimate the multipath rejection of an antenna arrangement, comparing a patch antenna sitting on a ground plane with the same antenna sitting on a choke ring (the pie pan variety described here a year or two ago). I could see no significant difference with the choke ring. I must say the site was decent with a clear view of the sky, but multipath on the code phase was quite evident with both antenna settings. Counselman in a 1981 paper stated (quoted in the above book) : "The multipath effects on carrier phases for relative positioning with short baselines should generally not be more than 1 cm." My observations are consistent with this. All this is somewhat off the topic of this group but I think it is interesting none the less. Brooks >From: "Gerry Creager N5JXS" > In fact, the experiments you performed, if well documented, would stand > up under scrutiny. One thing I'd suggest... and National Geodetic > Survey confirms: 4-hour occupations for geodetic work are necessary. > I've published on this, and will try to get that manuscript up on > http://page4.cs.tamu.edu/page4/ maybe next week ("How Long Must We > Wait?"). > > I find an error of slop a bit larger than I'd have expected or what I've > seen in some of MY ad hoc experiments, but not inexplicable. > > And, your point that the phase center of the L1 element for the > chokering-augmented antenna must be zero'd is completely accurate. The > L2 phase center must be well documented, as well. > > gerry > -- > "Eric G. Lemmon" wrote: > > > > Bob, > > > > I am not a GPS antenna expert, but I have experimented with a half-dozen or so > > antennas on an Ashtech centimeter-grade (carrier phase) GPS receiver and a > > Motorola Oncore VP timing receiver. When you are trying to establish the L1 > > carrier phase, any multipath signals can be extremely disruptive, and that is > > why choke-ring and other "low multipath" antennas were developed. However, > > the fancy machine work on the fins is only part of the high cost of such > > antennas. In order to establish a GPS position at the centimeter level (not > > to mention the millimeter level), the antenna must have a phase center that is > > exactly on the physical axis. This coincidence must be uniform at all points > > of the compass, from just above the horizon to the zenith. This is a tall > > order, and it involves not just precision design and manufacturing, but also > > some intensive calibration and alignment. > > > > One experiment I performed to verify this statement was to center a fairly > > inexpensive patch antenna on a level ground plane disk, with a clear view of > > the sky in all directions. I used my Ashtech receiver to record RINEX data in > > a number of two-hour sessions, rotating the disk on its axis a known angle > > between sessions. After post-processing the data, I noted a "slop" of nearly > > a meter in the position solution. I then repeated the test, using my Ashtech > > low-multipath antenna on the same mount, and found the position error to be > > less than 3 cm. > > > > Now, I know that this experiment will not stand up under scientific scrutiny, > > simply because a robust test requires several days, at various times of the > > day, and much longer occupations. Nevertheless, I know that precision > > positioning requires precision antennas. I am convinced that precision > > timing, which is sensitive to carrier phase, will also benefit from antennas > > which have a uniform phase response and freedom from multipath reception. A > > choke-ring antenna may be extreme overkill. I'd opt for a GPS antenna > > designed for timing reception. > > -- > Gerry Creager -- gerry@cs.tamu.edu --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 16 11:34:34 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id LAA14422 for ; Thu, 16 Aug 2001 11:34:31 -0500 (CDT) Message-ID: From: jim_johnson@agilent.com To: "TAPR Special Interest Group" Subject: [tacgps] RE: Homebrewed atomic standards??? Date: Thu, 16 Aug 2001 09:33:38 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Bob, Have been in class all week so am just now getting to emails. I'm glad to hear you might reconsider your atomic standards project. Time is probably better spent sitting by the pool with a refreshing beverage! Good luck - you sound like an active experimenter. 73, Jim W6SC > -----Original Message----- > From: Bob Smith [mailto:bobsmith5@home.com] > Sent: Saturday, August 11, 2001 8:44 AM > To: TAPR Special Interest Group > Subject: [tacgps] RE: Homebrewed atomic standards??? > > > Jim -- > > Thanks for the reality check. In fact, I have a fair > oscillator that I > am currently hand tracking to GPS using a home brew counter > timer chain > that will generate 1 PPS pulses at thumbwheel settable 1 mS intervals > and the 1 PPS from my M12 GPS as a scope trigger. The > oscillator is 40+ > years old and is getting a little (very) tired. Thus I lust after a > *really* stable oscillator. I'll reconsider the TOC > solution. I've got > the QST artical around here somewhere. > > So thanks, and back to my real homebrew! > > 73, de bob > > > jim_johnson@agilent.com wrote: > > > > Hi Bob, > > > > Wow, are you ever ambitious! My first question is, > > why would you want to do such a thing? You can get VERY > > good, nearly cesium-like performance these days (no more SA) > > by disciplining a good quartz oscillator with a GPS controller > > designed by Brooks Shera. In fact, a colleague of mine and > > I have done just that and we now have clocks that perform > > as well (sometimes better) than the HP 58503A, which sells > > for around $6,000. Our cost has been somewhere in the > > neighborhood of (I'm guessing at this) $300 plus the > > cost of the quartz oscillator and the GPS receiver. We > > were fortunate to have oscillators and GPS receivers lying > > around so we used what we had. > > > > As far as homebrewing atomic standards, the electronics > > could certainly be built as a hobby project (not for the > > faint of heart, however) but a cesium beam tube? Not a > > chance. For rubidium you need glassware (glass cell with > > Rb in it and a glass lamp with Rb) and a microwave cavity. > > Both the cesium beam tube and the lamp in the Rb have > > finite lifetimes, as opposed to quartz which should last > > forever. > > > > Putting it into perspective, you might have better > > luck homebrewing a jet aircraft than you would a cesium > > beam frequency standard - but I'm impressed with your level > > of ambition. Good luck! > > > > Jim Johnson > > Precision Instrumentation > > Agilent Laboratories > > Palo Alto, CA > > --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Tue Aug 28 01:04:33 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id BAA12346 for ; Tue, 28 Aug 2001 01:04:32 -0500 (CDT) From: "Steven Bible" To: "TAPR Special Interest Group" Subject: [tacgps] 2001 ARRL/TAPR DCC September 21-23, 2001 Date: Mon, 27 Aug 2001 23:06:38 -0700 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Importance: Normal List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk 2001 ARRL/TAPR Digital Communications Conference Cincinnati, Ohio September 21-23, 2001 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Hurry! Conference Room Rates end September 1st! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - DCC Schedule Highlights: Friday All Day APRS Seminar Saturday Technical Papers and Introductory Sessions Banquet Speaker and Prize Drawing Sunday - 5 Hour Seminar: "Simulating Circuits and Systems with Serenade SV" by Dave Newkirk, W9VES - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The 20th ARRL and TAPR Digital Communications Conference will be held September 21-23 in Cincinnati, Ohio. The annual gathering provides an international forum for radio amateurs involved in digital communication, networking, and related technologies to meet, publish their work, and present new ideas and techniques for discussion. The DCC is for technically oriented amateurs of all experience levels to exchange ideas and learn about recent hardware and software advances, theories, experimental results, and practical applications. Sessions at the beginner, intermediate, and advanced levels will be offered in selected areas of digital communication. Topics include APRS, satellite communication, TCP/IP, digital radio, spread spectrum and other introductory topics. Two symposia/seminars will be held which allow those with additional time and interest to make the most of the conference. For those who may have interest in just one symposium or seminar, registration for the conference is not required to attend these activities. The DCC banquet is Saturday night. A guest speaker will speak after the banquet and a prize drawing will top the evening. The Sunday morning seminar topic has not yet been announced. This year's fifth annual Automated Position Reporting System (APRS) National Symposium will be an all-day Friday event moderated by Steve Dimse, K4HG--the developer of javAPRS and www.findu.com. Possible attendees include APRS software authors such as Bob Bruninga, WB4APR--the father of APRS--Keith Sproul, WU2Z, and Mark Sproul, KB2ICI--the developers of MacAPRS and WinAPRS--Brent Hildebrand, KH2Z--the developer of APRSPLUS, Mike Musick, N0QBF--developer of PocketAPRS--and other nationally known APRS leaders. This session will include in-depth discussions and presentations on the status and future of APRS. It's a unique opportunity to gain insight into this fast-paced aspect of digital operation that combines computers, packet radio and GPS. Local co-hosts for the 2001 ARRL and TAPR DCC are Greater Cinti Amateur Radio Assn. http://w3.one.net/~rkuns/gcara.html DIAL Radio Club http://www.qsl.net/w8blv/Miami Valley FM Association http://www.mvfma.org/Southwest Ohio Digital Symposium http://w3.one.net/~rkuns/swohdigi.html Conference presentations, meetings, and seminars will be held at the Holiday Inn Cincinnati--Airport and Conference Center ; 859-371-2233. A special DCC room rate of $89/single and $89/double per night has been blocked for 50 rooms and is available until September 1. Once the 50 rooms have been reserved, room rates will increase. The hotel provides transportation to and from the Cincinnati/Northern Kentucky International Airport. Full information, a registration form, and hotel information also may be obtained by contacting Tucson Amateur Packet Radio, 972-671-TAPR (8277); fax 972-671-8716; e-mail: tapr@tapr.org. Conference registration includes the conference Proceedings, sessions, meetings, and lunch on Saturday. Registrations received before September 1 are $45. After September 1 or at the door, registration is $55. The banquet is $30. The APRS National Symposium on Friday is $25. The Sunday seminar is $20. --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 00:22:09 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id AAA16013 for ; Wed, 29 Aug 2001 00:22:01 -0500 (CDT) From: "Dr. Tom Clark" To: "TAPR Special Interest Group" Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? Date: Wed, 29 Aug 2001 01:21:22 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Importance: Normal List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Some of you may recall that a couple of years ago I posted the schematic for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. In conjunction with a project I'm doing, I had the need to dust off that design and make it into a PCB. In the next couple of weeks I'm going to send the board off to the PCB house to have a number of copies made and I'd like to know if any of you would like copies. You can see the essence of the schematic (the U1-U4 string) at URL ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. Except for a couple of MiniCircuit parts, all the parts are straight out of the DigiKey catalog and the PCB is designed to drop into a cheap case available from DigiKey if you want it to look nice. Here are some of the salient features: Frequency Standard Input: 5 or 10 MHz, jumper selected. Your standard feeds a directional coupler and amplifier (the MiniCircuits parts) so that the counter is isolated from the signal source. Normally the 5/10 MHz in/out is via PCB mounted BNCs, but the board has a large 0.1" grid kludge area, so you can mount a VCXO or TCXO "can" on the PCB. The kludge area could house a single IC doubler to give 10 MHz from a 5 MHz reference osc. Signal Outputs: - The "raw" frequency standard signal is looped thru via a 10 dB SMT directional coupler - 1 PPS, 1 kHz and a digital replica of the input, all driven by isolated Lo-Z 0/+5V digital drivers (using a circuit similar to the output drivers I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC connectors. The 1 PPS output has a 20%/80% duty cycle like the ONCORE. The 1 kHz output is a 40/60% (nearly) square-wave. Divider Synchronization: A CMOS level GPS 1PPS signal (like from a TAC-2) can be input to a PCB mounted BNC so that the divider chain can be synched to GPS time. Temp Monitor: For my application I needed temperature logging capability, so the PCB includes an RJ11 connector and room for two Dallas One-Wire DS1820 (TO92 case) temperature monitors (ignore if you don't need them). Power: +12V is regulated down to +5V with onboard 7805. Since the parts are easy to get from DigiKey, I'll probably just supply a couple of the harder to get parts (like the MiniCircuits widgets that have qty=25 ordering restrictions). But if the demand is there, I might consider doing a full parts kit. So please let me know if there is any interest (and your preferences on bare PCB vs kit). 73, Tom --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 00:51:39 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id AAA18293 for ; Wed, 29 Aug 2001 00:51:26 -0500 (CDT) Message-ID: From: "Kirby, Brian" To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? Date: Wed, 29 Aug 2001 00:48:50 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C1304E.47724CE0" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <8FC40EF9F4E4874CAD6CFD27344179E23B6EEF@UMS.MSFC.NASA.GOV> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ------_=_NextPart_001_01C1304E.47724CE0 Content-Type: text/plain I'm interested, let us know what the boards will cost. I just sent my rubidium out for calibration and found that one of my backup batteries leaked and it got my old divider board and part of the chassis. So I am starting over. This time the battery backup will be in a different chassis... > ---------- > From: Dr. Tom Clark[SMTP:tac@clark.net] > Reply To: TAPR Special Interest Group > Sent: Wednesday, August 29, 2001 12:21 AM > To: TAPR Special Interest Group > Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? > > Some of you may recall that a couple of years ago I posted the schematic > for a divider chain to bring your 5/10 MHz frequency standard down to > 1PPS. > In conjunction with a project I'm doing, I had the need to dust off that > design and make it into a PCB. In the next couple of weeks I'm going to > send > the board off to the PCB house to have a number of copies made and I'd > like > to know if any of you would like copies. You can see the essence of the > schematic (the U1-U4 string) at URL > ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. > > Except for a couple of MiniCircuit parts, all the parts are straight out > of > the DigiKey catalog > and the PCB is designed to drop into a cheap case available from DigiKey > if > you want it to look nice. > > Here are some of the salient features: > > Frequency Standard Input: 5 or 10 MHz, jumper selected. Your standard > feeds > a directional coupler and amplifier (the MiniCircuits parts) so that > the > counter is isolated from the signal source. Normally the 5/10 MHz in/out > is via PCB mounted BNCs, but the board has a large 0.1" grid kludge > area, > so you can mount a VCXO or TCXO "can" on the PCB. The kludge area could > house a single IC doubler to give 10 MHz from a 5 MHz reference osc. > > Signal Outputs: > - The "raw" frequency standard signal is looped thru via a 10 dB SMT > directional coupler > - 1 PPS, 1 kHz and a digital replica of the input, all driven by isolated > Lo-Z 0/+5V digital drivers (using a circuit similar to the output > drivers > I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC > connectors. The 1 PPS output has a 20%/80% duty cycle like the ONCORE. > The 1 kHz output is a 40/60% (nearly) square-wave. > > Divider Synchronization: A CMOS level GPS 1PPS signal (like from a TAC-2) > can be input to a PCB mounted BNC so that the divider chain can be > synched > to GPS time. > > Temp Monitor: For my application I needed temperature logging capability, > so the PCB includes an RJ11 connector and room for two Dallas One-Wire > DS1820 (TO92 case) temperature monitors (ignore if you don't need them). > > Power: +12V is regulated down to +5V with onboard 7805. > > Since the parts are easy to get from DigiKey, I'll probably just supply a > couple of the harder to get parts (like the MiniCircuits widgets that have > qty=25 ordering restrictions). But if the demand is there, I might > consider > doing a full parts kit. > > So please let me know if there is any interest (and your preferences on > bare > PCB vs kit). > > 73, Tom > > > --- > You are currently subscribed to tacgps as: brian.kirby@msfc.nasa.gov > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > ------_=_NextPart_001_01C1304E.47724CE0 Content-Type: text/html Content-Transfer-Encoding: quoted-printable RE: [tacgps] 5/10 MHz =3D> 1PPS PCBs. Interest?

I'm interested, let = us know what the boards will cost.  I just sent my rubidium out = for calibration and found that one of my backup batteries leaked and it = got my old divider board and part of the chassis.  So I am = starting over.  This time the battery backup will be in a = different chassis...

    ----------
    From:   = Dr. Tom = Clark[SMTP:tac@clark.net]
    Reply To: =       TAPR Special Interest Group
    Sent:   = Wednesday, August 29, 2001 12:21 = AM
    To: =     TAPR Special = Interest Group
    Subject: =        [tacgps] 5/10 MHz =3D> 1PPS PCBs. Interest?

    Some of you may recall that a couple = of years ago I posted the schematic
    for a divider chain to bring your = 5/10 MHz frequency standard down to 1PPS.
    In conjunction with a project I'm = doing, I had the need to dust off that
    design and make it into a PCB. In the = next couple of weeks I'm going to send
    the board off to the PCB house to = have a number of copies made and I'd like
    to know if any of you would like = copies. You can see the essence of the
    schematic (the U1-U4 string) at = URL
         = ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pd= f.

    Except for a couple of MiniCircuit = parts, all the parts are straight out of
    the DigiKey catalog
    and the PCB is designed to drop into = a cheap case available from DigiKey if
    you want it to look nice.

    Here are some of the salient = features:

    Frequency Standard Input: 5 or 10 MHz, = jumper selected. Your standard feeds
      a directional coupler and = amplifier (the  MiniCircuits parts) so that the
      counter is isolated from the = signal source. Normally the 5/10 MHz in/out
      is via PCB mounted BNCs, but = the board has a large 0.1" grid kludge area,
      so you can mount a VCXO or = TCXO "can" on the PCB. The kludge area could
      house a single IC doubler to = give 10 MHz from a 5 MHz reference osc.

    Signal Outputs:
     - The "raw" frequency = standard signal is looped thru via a 10 dB SMT
       directional = coupler
     - 1 PPS, 1 kHz and a digital = replica of the input, all driven by isolated
       Lo-Z 0/+5V digital = drivers (using a circuit similar to the output drivers
       I used for the = 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC
       connectors. The 1 PPS = output has a 20%/80% duty cycle like the ONCORE.
       The 1 kHz output is a = 40/60% (nearly) square-wave.

    Divider Synchronization: A CMOS level = GPS 1PPS signal (like from a TAC-2)
      can be input to a PCB mounted = BNC so that the divider chain can be synched
      to GPS time.

    Temp Monitor: For my application I = needed temperature logging capability,
      so the PCB includes an RJ11 = connector and room for two Dallas One-Wire
      DS1820 (TO92 case) temperature = monitors (ignore if you don't need them).

    Power: +12V is regulated down to +5V = with onboard 7805.

    Since the parts are easy to get from = DigiKey, I'll probably just supply a
    couple of the harder to get parts = (like the MiniCircuits widgets that have
    qty=3D25 ordering restrictions). But = if the demand is there, I might consider
    doing a full parts kit.

    So please let me know if there is any = interest (and your preferences on bare
    PCB vs kit).

    73, Tom


    ---
    You are currently subscribed to = tacgps as: brian.kirby@msfc.nasa.gov
    To unsubscribe send a blank email to = leave-tacgps-6754G@lists.tapr.org

------_=_NextPart_001_01C1304E.47724CE0-- --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 05:34:29 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id FAA13068 for ; Wed, 29 Aug 2001 05:34:27 -0500 (CDT) Message-Id: X-Sender: glittle@awod.com Date: Wed, 29 Aug 2001 06:32:47 -0400 To: "TAPR Special Interest Group" From: Glenn Little Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <4.3.2.7.1.20010829062743.00e7a100@awod.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Tom I would be interested in one of the boards. About the DS1820. This is a now obsolete part. The part is next to imposible to find. We use it at work. The replacement is a DS18S20. If you are using the chip in parisite power mode, you have to short two of the pins together. This drove us crazy trying to find out why the DS18S20 would not work in place of the DS1820. I can get the details on Tuesday. I will be leaving town today and away from email. 73 Glenn WB4UIV At 01:21 AM 8/29/01 -0400, you wrote: >Some of you may recall that a couple of years ago I posted the schematic >for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. >In conjunction with a project I'm doing, I had the need to dust off that >design and make it into a PCB. In the next couple of weeks I'm going to send >the board off to the PCB house to have a number of copies made and I'd like >to know if any of you would like copies. You can see the essence of the >schematic (the U1-U4 string) at URL > ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. > >Except for a couple of MiniCircuit parts, all the parts are straight out of >the DigiKey catalog >and the PCB is designed to drop into a cheap case available from DigiKey if >you want it to look nice. > >Here are some of the salient features: > >Frequency Standard Input: 5 or 10 MHz, jumper selected. Your standard feeds > a directional coupler and amplifier (the MiniCircuits parts) so that the > counter is isolated from the signal source. Normally the 5/10 MHz in/out > is via PCB mounted BNCs, but the board has a large 0.1" grid kludge area, > so you can mount a VCXO or TCXO "can" on the PCB. The kludge area could > house a single IC doubler to give 10 MHz from a 5 MHz reference osc. > >Signal Outputs: > - The "raw" frequency standard signal is looped thru via a 10 dB SMT > directional coupler > - 1 PPS, 1 kHz and a digital replica of the input, all driven by isolated > Lo-Z 0/+5V digital drivers (using a circuit similar to the output drivers > I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC > connectors. The 1 PPS output has a 20%/80% duty cycle like the ONCORE. > The 1 kHz output is a 40/60% (nearly) square-wave. > >Divider Synchronization: A CMOS level GPS 1PPS signal (like from a TAC-2) > can be input to a PCB mounted BNC so that the divider chain can be synched > to GPS time. > >Temp Monitor: For my application I needed temperature logging capability, > so the PCB includes an RJ11 connector and room for two Dallas One-Wire > DS1820 (TO92 case) temperature monitors (ignore if you don't need them). > >Power: +12V is regulated down to +5V with onboard 7805. > >Since the parts are easy to get from DigiKey, I'll probably just supply a >couple of the harder to get parts (like the MiniCircuits widgets that have >qty=25 ordering restrictions). But if the demand is there, I might consider >doing a full parts kit. > >So please let me know if there is any interest (and your preferences on bare >PCB vs kit). > >73, Tom > > >--- >You are currently subscribed to tacgps as: GLITTLE@AWOD.COM >To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --------------------------------------------------------------------------- Glenn Little glittle@awod.com QCWA LM 28417 Amateur Callsign: WB4UIV wb4uiv@amsat.org AMSAT LM 2178 QTH: Goose Creek, SC USA (EM92xx) ARRL TAPR --------------------------------------------------------------------------- --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 07:46:05 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id HAA25269 for ; Wed, 29 Aug 2001 07:46:00 -0500 (CDT) Reply-To: "TAPR Special Interest Group" From: "W3SZ R Rehr" To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? Date: Wed, 29 Aug 2001 08:44:40 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600 In-Reply-To: Importance: Normal List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: <001501c13088$5f8ac520$0300a8c0@rrehr> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk HI, Tom! Thanks for the note to the list. I'd be interested in whatever you decide to put together...board, partial parts, or full parts list. Full parts list would be ideal, but I'll take what I can get. Thanks again! 73, Roger Rehr W3SZ ex AA3QK, WA3JYM FN20ah 2 Merrymount Road Reading, PA 19609-1718 http://www.qsl.net/w3sz > -----Original Message----- > From: bounce-tacgps-23685@lists.tapr.org > [mailto:bounce-tacgps-23685@lists.tapr.org]On Behalf Of Dr. Tom Clark > Sent: Wednesday, August 29, 2001 1:21 AM > To: TAPR Special Interest Group > Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? > > > Some of you may recall that a couple of years ago I posted > the schematic > for a divider chain to bring your 5/10 MHz frequency standard > down to 1PPS. > In conjunction with a project I'm doing, I had the need to > dust off that > design and make it into a PCB. In the next couple of weeks > I'm going to send > the board off to the PCB house to have a number of copies > made and I'd like > to know if any of you would like copies. You can see the > essence of the > schematic (the U1-U4 string) at URL > ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. > > Except for a couple of MiniCircuit parts, all the parts are > straight out of > the DigiKey catalog > and the PCB is designed to drop into a cheap case available > from DigiKey if > you want it to look nice. > > Here are some of the salient features: > > Frequency Standard Input: 5 or 10 MHz, jumper selected. Your > standard feeds > a directional coupler and amplifier (the MiniCircuits > parts) so that the > counter is isolated from the signal source. Normally the > 5/10 MHz in/out > is via PCB mounted BNCs, but the board has a large 0.1" > grid kludge area, > so you can mount a VCXO or TCXO "can" on the PCB. The > kludge area could > house a single IC doubler to give 10 MHz from a 5 MHz reference osc. > > Signal Outputs: > - The "raw" frequency standard signal is looped thru via a 10 dB SMT > directional coupler > - 1 PPS, 1 kHz and a digital replica of the input, all > driven by isolated > Lo-Z 0/+5V digital drivers (using a circuit similar to the > output drivers > I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC > connectors. The 1 PPS output has a 20%/80% duty cycle like > the ONCORE. > The 1 kHz output is a 40/60% (nearly) square-wave. > > Divider Synchronization: A CMOS level GPS 1PPS signal (like > from a TAC-2) > can be input to a PCB mounted BNC so that the divider chain > can be synched > to GPS time. > > Temp Monitor: For my application I needed temperature logging > capability, > so the PCB includes an RJ11 connector and room for two > Dallas One-Wire > DS1820 (TO92 case) temperature monitors (ignore if you > don't need them). > > Power: +12V is regulated down to +5V with onboard 7805. > > Since the parts are easy to get from DigiKey, I'll probably > just supply a > couple of the harder to get parts (like the MiniCircuits > widgets that have > qty=25 ordering restrictions). But if the demand is there, I > might consider > doing a full parts kit. > > So please let me know if there is any interest (and your > preferences on bare > PCB vs kit). > > 73, Tom --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 08:40:05 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id IAA28724 for ; Wed, 29 Aug 2001 08:40:04 -0500 (CDT) From: "John K. Pringle" To: "TAPR Special Interest Group" Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? Date: Wed, 29 Aug 2001 09:39:09 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom -- Put me down for 3 of the boards. Let me know cost and other details. Thanks. John W4SF mailto:jprongle@tampabay.rr.com --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 09:21:34 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id JAA03107 for ; Wed, 29 Aug 2001 09:21:33 -0500 (CDT) Message-ID: Date: Wed, 29 Aug 2001 16:19:04 +0200 From: Alberto di Bene X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B8CF9D7.B420A613@usa.net> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi all, talking of PCBs, does anybody know if/where it exists a PCB for the Analog Device AD9854 DDS ? I obtained this chip as a sample from AD, but it has so many pins, and so close each other that I feel I won't be able to produce myself a PCB with the usual techniques used for ham projects. Ideally it should only bring each pin to a larger connection pad, which then I could use to access the chip. TNX for any info 73 Alberto I2PHD --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 10:05:08 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id KAA06787 for ; Wed, 29 Aug 2001 10:05:06 -0500 (CDT) Message-ID: From: "Chuck Pinkham" To: "TAPR Special Interest Group" References: Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? Date: Wed, 29 Aug 2001 11:02:57 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <001601c1309b$b0c43f80$6e6419ac@sr963c> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Tom, I am interested in two boards. Kits are always nice, but just the boards and MIniCircuits stuff is ok. Thanks, Chuck ----- Original Message ----- From: "Dr. Tom Clark" To: "TAPR Special Interest Group" Sent: Wednesday, August 29, 2001 1:21 AM Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? | Some of you may recall that a couple of years ago I posted the schematic | for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. | In conjunction with a project I'm doing, I had the need to dust off that | design and make it into a PCB. In the next couple of weeks I'm going to send | the board off to the PCB house to have a number of copies made and I'd like | to know if any of you would like copies. You can see the essence of the | schematic (the U1-U4 string) at URL | ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. | | Except for a couple of MiniCircuit parts, all the parts are straight out of | the DigiKey catalog | and the PCB is designed to drop into a cheap case available from DigiKey if | you want it to look nice. | | Here are some of the salient features: | | Frequency Standard Input: 5 or 10 MHz, jumper selected. Your standard feeds | a directional coupler and amplifier (the MiniCircuits parts) so that the | counter is isolated from the signal source. Normally the 5/10 MHz in/out | is via PCB mounted BNCs, but the board has a large 0.1" grid kludge area, | so you can mount a VCXO or TCXO "can" on the PCB. The kludge area could | house a single IC doubler to give 10 MHz from a 5 MHz reference osc. | | Signal Outputs: | - The "raw" frequency standard signal is looped thru via a 10 dB SMT | directional coupler | - 1 PPS, 1 kHz and a digital replica of the input, all driven by isolated | Lo-Z 0/+5V digital drivers (using a circuit similar to the output drivers | I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC | connectors. The 1 PPS output has a 20%/80% duty cycle like the ONCORE. | The 1 kHz output is a 40/60% (nearly) square-wave. | | Divider Synchronization: A CMOS level GPS 1PPS signal (like from a TAC-2) | can be input to a PCB mounted BNC so that the divider chain can be synched | to GPS time. | | Temp Monitor: For my application I needed temperature logging capability, | so the PCB includes an RJ11 connector and room for two Dallas One-Wire | DS1820 (TO92 case) temperature monitors (ignore if you don't need them). | | Power: +12V is regulated down to +5V with onboard 7805. | | Since the parts are easy to get from DigiKey, I'll probably just supply a | couple of the harder to get parts (like the MiniCircuits widgets that have | qty=25 ordering restrictions). But if the demand is there, I might consider | doing a full parts kit. | | So please let me know if there is any interest (and your preferences on bare | PCB vs kit). | | 73, Tom | | | --- | You are currently subscribed to tacgps as: k3per@arrl.net | To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org | --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 11:29:43 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id LAA14582 for ; Wed, 29 Aug 2001 11:29:43 -0500 (CDT) Date: Wed, 29 Aug 2001 11:29:02 -0500 (CDT) From: John Koster To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk I don't know what kind of package the Analog Device AD9854 comes in, but as for concept, look at this: http://www.jdr.com/interact/item.asp?itemno=gr-cgn-1001 I don't recall where, but I think I have seen them for SMT parts as well as for a broader range of PLCC parts than this link shows. Besides lurking the JDR site, you might try Jameco or Digikey. Or perhaps a general web search for prototyping + your package type. There's a lot of stuff out there from small unknown organizations. Good luck. John Koster, W9DDD On Wed, 29 Aug 2001, Alberto di Bene wrote: > Hi all, > talking of PCBs, does anybody know if/where it exists a PCB > for the Analog Device AD9854 DDS ? > > I obtained this chip as a sample from AD, but it has so many pins, > and so close each other that I feel I won't be able to produce myself > a PCB with the usual techniques used for ham projects. > > Ideally it should only bring each pin to a larger connection pad, which > then I could use to access the chip. > > TNX for any info > > 73 Alberto I2PHD > > > > --- > You are currently subscribed to tacgps as: W9DDD@TAPR.ORG > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > > --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 13:32:20 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id NAA26153 for ; Wed, 29 Aug 2001 13:32:20 -0500 (CDT) Date: Wed, 29 Aug 2001 13:31:36 -0500 (CDT) From: John Koster To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk You might also find the following of interest. http://members.iinet.net.au/~richardh/Direct%20Digital%20Synthesizer%20using%20the%20AD9854%20quadrature%20DDS.htm John Koster, W9DDD On Wed, 29 Aug 2001, Alberto di Bene wrote: > Hi all, > talking of PCBs, does anybody know if/where it exists a PCB > for the Analog Device AD9854 DDS ? > > I obtained this chip as a sample from AD, but it has so many pins, > and so close each other that I feel I won't be able to produce myself > a PCB with the usual techniques used for ham projects. > > Ideally it should only bring each pin to a larger connection pad, which > then I could use to access the chip. > > TNX for any info > > 73 Alberto I2PHD > > > > --- > You are currently subscribed to tacgps as: W9DDD@TAPR.ORG > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org > > --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 14:27:10 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id OAA01872 for ; Wed, 29 Aug 2001 14:27:05 -0500 (CDT) X-Originating-IP: 199.46.198.231 X-URL: http://www.mail2web.com/ Subject: [tacgps] =?iso-8859-1?Q?RE: 5/10 MHz =3D> 1PPS PCBs. Interest??= Sender: bounce-tacgps-6754@lists.tapr.org From: "paulnocella@sprintmail.com" Date: Wed, 29 Aug 2001 15:26:26 -0400 To: "TAPR Special Interest Group" Reply-To: "TAPR Special Interest Group" X-Priority: 3 X-MSMail-Priority: Normal MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-ID: X-OriginalArrivalTime: 29 Aug 2001 19:28:47.0625 (UTC) FILETIME=[D3141F90:01C130C0] List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: Precedence: bulk Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from Quoted-Printable to 8bit by tapr.org id OAA01872 Hi Tom, Yes, I could use two kits (or at least just the boards if that is all that is available) Many thanks for allowing us this opportunity ! Paul, WB2SKC Original Message: ----------------- From: Dr. Tom Clark tac@clark.net Date: Wed, 29 Aug 2001 01:21:22 -0400 To: tacgps@lists.tapr.org Subject: [tacgps] 5/10 MHz => 1PPS PCBs. Interest? Some of you may recall that a couple of years ago I posted the schematic for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. In conjunction with a project I'm doing, I had the need to dust off that design and make it into a PCB. In the next couple of weeks I'm going to send the board off to the PCB house to have a number of copies made and I'd like to know if any of you would like copies. You can see the essence of the schematic (the U1-U4 string) at URL ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. Except for a couple of MiniCircuit parts, all the parts are straight out of the DigiKey catalog and the PCB is designed to drop into a cheap case available from DigiKey if you want it to look nice. Here are some of the salient features: Frequency Standard Input: 5 or 10 MHz, jumper selected. Your standard feeds a directional coupler and amplifier (the MiniCircuits parts) so that the counter is isolated from the signal source. Normally the 5/10 MHz in/out is via PCB mounted BNCs, but the board has a large 0.1" grid kludge area, so you can mount a VCXO or TCXO "can" on the PCB. The kludge area could house a single IC doubler to give 10 MHz from a 5 MHz reference osc. Signal Outputs: - The "raw" frequency standard signal is looped thru via a 10 dB SMT directional coupler - 1 PPS, 1 kHz and a digital replica of the input, all driven by isolated Lo-Z 0/+5V digital drivers (using a circuit similar to the output drivers I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC connectors. The 1 PPS output has a 20%/80% duty cycle like the ONCORE. The 1 kHz output is a 40/60% (nearly) square-wave. Divider Synchronization: A CMOS level GPS 1PPS signal (like from a TAC-2) can be input to a PCB mounted BNC so that the divider chain can be synched to GPS time. Temp Monitor: For my application I needed temperature logging capability, so the PCB includes an RJ11 connector and room for two Dallas One-Wire DS1820 (TO92 case) temperature monitors (ignore if you don't need them). Power: +12V is regulated down to +5V with onboard 7805. Since the parts are easy to get from DigiKey, I'll probably just supply a couple of the harder to get parts (like the MiniCircuits widgets that have qty=25 ordering restrictions). But if the demand is there, I might consider doing a full parts kit. So please let me know if there is any interest (and your preferences on bare PCB vs kit). 73, Tom --- You are currently subscribed to tacgps as: PAULNOCELLA@SPRINTMAIL.COM To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org -------------------------------------------------------------------- Mail2Web - Check your email from the web at http://www.mail2web.com/ . --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 16:47:00 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id QAA16252 for ; Wed, 29 Aug 2001 16:46:59 -0500 (CDT) Date: Wed, 29 Aug 2001 16:46:27 Subject: [tacgps] newbie question To: "TAPR Special Interest Group" From: "Allan Liu" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" Sender: bounce-tacgps-6754@lists.tapr.org Message-Id: Precedence: bulk Hi, I am new to the entire issue of time. I am currently trying to build a box to measure network performance. One of the things that I will need is an accurate timestamp, down to the 100 microseconds. I have been doing a bit of reading on the web and I believe I know how to accomplish this using a GPS receiver with ASCII date/time output and a 1PPS output. I don't understand what the TAC2 platform provides that the Garmin GPS25 does not provide. In other words, why would I need to buy a TAC2 kit. As I understand from Garmin's datasheet, the GPS25 board offers both an ASCII date/time output as well as a 1PPS output. Am I missing something? Thanks. Regards, -Allan --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 20:21:15 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id UAA01706 for ; Wed, 29 Aug 2001 20:21:12 -0500 (CDT) Message-ID: Date: Wed, 29 Aug 2001 21:20:38 -0400 From: GS Organization: bigfoot.com X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B8D94E6.4CF30669@bigfoot.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk "Dr. Tom Clark" wrote: > > So please let me know if there is any interest (and your preferences on bare > PCB vs kit). I'd be interested in one, preferably a kit, but a bare board with the hard to find parts would be fine also. Gary Sanders --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Wed Aug 29 23:58:26 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id XAA17796 for ; Wed, 29 Aug 2001 23:58:26 -0500 (CDT) Date: Wed, 29 Aug 2001 21:53:17 -0700 From: Steve Share Subject: [tacgps] RE: tacgps digest: August 29, 2001 To: "TAPR Special Interest Group" Message-id: X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2462.0000 Content-transfer-encoding: 7BIT Importance: Normal X-Priority: 3 (Normal) X-MSMail-priority: Normal List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom, I'd be interested in 2, kits preferred over PCB only. Thanks, Steve Share > Subject: 5/10 MHz => 1PPS PCBs. Interest? > From: "Dr. Tom Clark" > Date: Wed, 29 Aug 2001 01:21:22 -0400 > X-Message-Number: 1 > > Some of you may recall that a couple of years ago I posted > the schematic > for a divider chain to bring your 5/10 MHz frequency standard > down to 1PPS. > In conjunction with a project I'm doing, I had the need to > dust off that > design and make it into a PCB. In the next couple of weeks > I'm going to send > the board off to the PCB house to have a number of copies > made and I'd like > to know if any of you would like copies. You can see the > essence of the > schematic (the U1-U4 string) at URL > ftp://aleph.gsfc.nasa.gov/GPS/toc/rubidium/counters.pdf. > > Except for a couple of MiniCircuit parts, all the parts are > straight out of > the DigiKey catalog > and the PCB is designed to drop into a cheap case available > from DigiKey if > you want it to look nice. > > Here are some of the salient features: > > Frequency Standard Input: 5 or 10 MHz, jumper selected. Your > standard feeds > a directional coupler and amplifier (the MiniCircuits > parts) so that the > counter is isolated from the signal source. Normally the > 5/10 MHz in/out > is via PCB mounted BNCs, but the board has a large 0.1" > grid kludge area, > so you can mount a VCXO or TCXO "can" on the PCB. The > kludge area could > house a single IC doubler to give 10 MHz from a 5 MHz reference osc. > > Signal Outputs: > - The "raw" frequency standard signal is looped thru via a 10 dB SMT > directional coupler > - 1 PPS, 1 kHz and a digital replica of the input, all > driven by isolated > Lo-Z 0/+5V digital drivers (using a circuit similar to the > output drivers > I used for the 1PPSoutputs on the TAC-2 board) with PCB-mounted BNC > connectors. The 1 PPS output has a 20%/80% duty cycle like > the ONCORE. > The 1 kHz output is a 40/60% (nearly) square-wave. > > Divider Synchronization: A CMOS level GPS 1PPS signal (like > from a TAC-2) > can be input to a PCB mounted BNC so that the divider chain > can be synched > to GPS time. > > Temp Monitor: For my application I needed temperature logging > capability, > so the PCB includes an RJ11 connector and room for two > Dallas One-Wire > DS1820 (TO92 case) temperature monitors (ignore if you > don't need them). > > Power: +12V is regulated down to +5V with onboard 7805. > > Since the parts are easy to get from DigiKey, I'll probably > just supply a > couple of the harder to get parts (like the MiniCircuits > widgets that have > qty=25 ordering restrictions). But if the demand is there, I > might consider > doing a full parts kit. > > So please let me know if there is any interest (and your > preferences on bare > PCB vs kit). > > 73, Tom --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 00:18:27 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id AAA25675 for ; Thu, 30 Aug 2001 00:18:26 -0500 (CDT) Message-Id: X-Sender: rhamstra@shell12.ba.best.com Date: Wed, 29 Aug 2001 22:15:48 -0700 To: "TAPR Special Interest Group" From: "Robert H. Hamstra, Jr." Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? In-Reply-To: Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="=====================_1026778609==_.ALT" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <4.3.2.7.2.20010829221127.00dd29d0@shell12.ba.best.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk --=====================_1026778609==_.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed Hi, I am interested in one bare PCB with MiniCircuit parts, if possible. Thanks, Bob Hamstra At 01:21 8/29/01 -0400, you wrote: >Some of you may recall that a couple of years ago I posted the schematic >for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. ------------------------------------------------------------------------------- Robert H. Hamstra, Jr. - Circuit Solutions, San Jose, CA 95129 RHamstra@CirSol.com Voice: (408) 996-2166 Fax: (408) 446-9471 http://www.cirsol.com --=====================_1026778609==_.ALT Content-Type: text/html; charset="us-ascii" Hi,

I am interested in one bare PCB with MiniCircuit parts, if possible.

Thanks,

Bob Hamstra

At 01:21 8/29/01 -0400, you wrote:
Some of you may recall that a couple of years ago I posted the schematic
for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS.


-------------------------------------------------------------------------------
 Robert H. Hamstra, Jr. - Circuit Solutions, San Jose, CA 95129
 RHamstra@CirSol.com  Voice: (408) 996-2166  Fax: (408) 446-9471
--=====================_1026778609==_.ALT-- --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 01:42:58 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id BAA01497 for ; Thu, 30 Aug 2001 01:42:52 -0500 (CDT) Message-Id: To: "TAPR Special Interest Group" From: clemens@dwf.com Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? In-Reply-To: Your message of "Wed, 29 Aug 2001 01:21:22 EDT." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Thu, 30 Aug 2001 00:41:52 -0600 Sender: bounce-tacgps-6754@lists.tapr.org List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <200108300641.f7U6fqN01522@orion.dwf.com> Precedence: bulk Id be interested in one. A kit would be easier, but the bare board+ would be fine. -- Reg.Clemens reg@dwf.com --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 02:02:39 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id CAA03015 for ; Thu, 30 Aug 2001 02:02:34 -0500 (CDT) Message-ID: Date: Thu, 30 Aug 2001 03:01:45 -0400 From: Boyd Prestwood K5YKG Reply-To: "TAPR Special Interest Group" X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: <3B8DE4D9.AE692013@netcarrier.com> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk "Dr. Tom Clark" wrote: > Some of you may recall that a couple of years ago I posted the schematic > for a divider chain to bring your 5/10 MHz frequency standard down to 1PPS. Sounds like another fun project. I'd be interested in a bare board or kit, whatever you decide to put together. Thanks for the offering. Boyd Prestwood, K5YKG --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 07:20:40 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id HAA03153 for ; Thu, 30 Aug 2001 07:20:35 -0500 (CDT) Date: Thu, 30 Aug 2001 08:19:56 -0400 From: John Ackermann N8UR To: "TAPR Special Interest Group" Subject: [tacgps] Re: newbie question Message-ID: In-Reply-To: References: List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <1649431.999159596@WUSJA129861-8HP> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk X-Mailer: Mulberry/2.1.0b3 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline --On Wednesday, August 29, 2001 4:46 PM +0000 Allan Liu wrote: > Hi, > > I am new to the entire issue of time. I am currently trying to build a > box to measure network performance. One of the things that I will need > is an accurate timestamp, down to the 100 microseconds. I have been > doing a bit of reading on the web and I believe I know how to accomplish > this using a GPS receiver with ASCII date/time output and a 1PPS output. > > I don't understand what the TAC2 platform provides that the Garmin GPS25 > does not provide. In other words, why would I need to buy a TAC2 kit. > As I understand from Garmin's datasheet, the GPS25 board offers both an > ASCII date/time output as well as a 1PPS output. Am I missing > something? Thanks. Hi Allan -- The TAC provides a fairly elegant interface to the Garmin or Motorola GPS receiver. You can get the 1PPS off the receiver without it, but it provides regulated voltage for the receiver, two serial ports, and two low-Z buffered 1PPS outputs. Just makes life a bit easier than having to haywire everything to the 10 pin connector on the receiver. John ---- John Ackermann N8UR jra@febo.com http://www.febo.com President, TAPR n8ur@tapr.org http://www.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 22:58:58 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id WAA13957 for ; Thu, 30 Aug 2001 22:58:55 -0500 (CDT) From: "Dr. Tom Clark" To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? Date: Thu, 30 Aug 2001 23:58:11 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Importance: Normal In-Reply-To: List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Thanks to all for the quick reply. So far the requests total about 30, so this will clearly justify doing an extra run. I got the prototype running fine yesterday. First, let me give a brief explanation on why I'm doing this board. In June I decided to retire from NASA/GSFC (although I still have a presence there as an Emeritus scientist). I took on a part-time relation as a Senior Scientist at Syntonics (http://www.SyntonicsCorp.com) -- this firm spun off from Johns Hopkins Applied Physics Lab to commercialize the extremely high-quality xtal oscillators that JPL had provided for many DoD and Deep Space missions. At Syntonics, I have been working on developing techniques to array N oscillators to try to extract a sqrt(N) performance improvement as well as improved reliability. To try to design the optimum combiner, it became obvious that we needed a good statistical characterization of just what is noisy in various oscillators and what effects performance. To do this, I decided that we needed to be able to measure the Allan Variance on a number of oscillators of different degrees of "goodness" -- ranging from Rubes and high quality xtals all the way down to cheap crystal can oscillators. To accomplish this we have adapted Rick's TAC32Plus so that it can support simultaneous TIC measurements on up to 8 HP53131/2 counters, and I developed the small "test pod" divider chain that I described to you a couple of days ago. Right now we are doing 3-way tests to see if we can identify "problem children" from their integrated time-difference performance. In case you'd like to see more about the divider PCB I've been working on, the schematic is posted for review on my NASA/GSFC FTP server at ftp://aleph.gsfc.nasa.gov/GPS/dividers/tac-div.pdf and a photo of the PCB can be seen at ftp://aleph.gsfc.nasa.gov/GPS/dividers/tac-div.jpg. In the photo you see the PCB resting in the bottom half of the cheap Hammond box that the project was designed to fit into. Let me answer a couple of questions that were raised after my initial posting. Jeff Vollin questioned the fact that I used simple ripple counters (74HC390s) instead of more quiet synchronous counters. The basic answer is that the project I described is based on the longer term Allan Variance details. Short-term "phase" noise from the ripple counters is pretty irrelevant. Simplicity/cost considerations led to the use of simple ripple counters (but on the initial prototype I'm seeing pulse-to-pulse jitter of a nsec or less even with the ripple counters). I agree that the best approach would be to use an FPGA, but I'm still illiterate (and lacking design tools) in VHDL! Glenn Little pointed out that the DS1820 is an obsolete part, now replaced by the 18S20. Yep -- I just used the "1820" name to describe the generic device type. When you look at the photo, you will see the holes for the 18S20 indicated; the DC power and RJ11 1-wire LAN connects thru a single-piece Hirose connector mounted on the PCB (although for right now, power for the unit under test is coming thru the red/blk twisted pair). This was included because >>THE<< principal effect on xtal oscillators comes from their temperature environment. As the "test pod" is cycled, I wanted to be able to follow the temperature of the oscillator can. I've also been using the DS1920 iButton version of the 1820, and the DS1921 temperature logging iButton is really a neat tool. 73, Tom --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Thu Aug 30 23:06:24 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id XAA14306 for ; Thu, 30 Aug 2001 23:06:21 -0500 (CDT) From: "Dr. Tom Clark" To: "TAPR Special Interest Group" Cc: "TACGPS" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? Date: Fri, 31 Aug 2001 00:05:47 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Importance: Normal In-Reply-To: List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Lyle asked (while I was typing in my other message): > Any idea of the price for aboard and the hard-to-get parts? I'm > interested, I think :-) Don't know PCB costs yet. There are only a couple on hard-to-get (i.e. non-DigiKey) parts, a ~$6 SMT 9dB direction coupler and an $2 ERA-3 MMIC. The only reason they are hard to get is the MiniCircuits has a order minimum. The PCB BNCs and the Hammond cabinet are the most expensive parts. Everything else is pure Popcorn! > Want to put all the logic in a single CPLD or FPGA? I sorta answered this in my posting of a few minutes ago. That's a technology I need to learn. But because this device is price dominated by cabinet, connectors and SMT RF parts, I doubt that an FPGA would save much. 73, Tom --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 31 04:04:02 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id EAA13423 for ; Fri, 31 Aug 2001 04:04:01 -0500 (CDT) Message-ID: From: "Holger Hey Mortensen" To: "TAPR Special Interest Group" References: Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? Date: Fri, 31 Aug 2001 09:02:06 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" X-Priority: 3 X-MSMail-Priority: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <001401c131fb$9d517c40$7001a8c0@test> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by tapr.org id EAA13423 Hej Tom I am interested in one bare PCB with MiniCircuit parts, if possible. Thanks Holger Mortensen / OX3HI --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 31 07:35:58 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id HAA26061 for ; Fri, 31 Aug 2001 07:35:54 -0500 (CDT) Message-ID: Date: Fri, 31 Aug 2001 08:31:45 -0400 From: Bill Powell Reply-To: "TAPR Special Interest Group" X-Accept-Language: en,pdf MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re>RE: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio X-Message-Id: <3B8F83B1.4761BDF5@intrex.net> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom, I'd be interested in 4 boards/hard to find parts, or any grouping of parts that includes the boards. Thanks, Bill Powell af4jg bpowell@intrex.net "Dr. Tom Clark" wrote: > > Thanks to all for the quick reply. So far the requests total about 30, so > this will clearly justify doing an extra run. I got the prototype running > fine yesterday. > > First, let me give a brief explanation on why I'm doing this board. In June > I decided to retire from NASA/GSFC (although I still have a presence there > as an Emeritus scientist). I took on a part-time relation as a Senior > Scientist at Syntonics (http://www.SyntonicsCorp.com) -- this firm spun off > from Johns Hopkins Applied Physics Lab to commercialize the extremely > high-quality xtal oscillators that JPL had provided for many DoD and Deep > Space missions. > > At Syntonics, I have been working on developing techniques to array N > oscillators to try to extract a sqrt(N) performance improvement as well as > improved reliability. To try to design the optimum combiner, it became > obvious that we needed a good statistical characterization of just what is > noisy in various oscillators and what effects performance. > > To do this, I decided that we needed to be able to measure the Allan > Variance on a number of oscillators of different degrees of "goodness" -- > ranging from Rubes and high quality xtals all the way down to cheap crystal > can oscillators. To accomplish this we have adapted Rick's TAC32Plus so that > it can support simultaneous TIC measurements on up to 8 HP53131/2 counters, > and I developed the small "test pod" divider chain that I described to you a > couple of days ago. Right now we are doing 3-way tests to see if we can > identify "problem children" from their integrated time-difference > performance. > > In case you'd like to see more about the divider PCB I've been working on, > the schematic is posted for review on my NASA/GSFC FTP server at > ftp://aleph.gsfc.nasa.gov/GPS/dividers/tac-div.pdf and a photo of the PCB > can be seen at ftp://aleph.gsfc.nasa.gov/GPS/dividers/tac-div.jpg. In the > photo you see the PCB resting in the bottom half of the cheap Hammond box > that the project was designed to fit into. > > Let me answer a couple of questions that were raised after my initial > posting. Jeff Vollin questioned the fact that I used simple ripple counters > (74HC390s) instead of more quiet synchronous counters. The basic answer is > that the project I described is based on the longer term Allan Variance > details. Short-term "phase" noise from the ripple counters is pretty > irrelevant. Simplicity/cost considerations led to the use of simple ripple > counters (but on the initial prototype I'm seeing pulse-to-pulse jitter of a > nsec or less even with the ripple counters). I agree that the best approach > would be to use an FPGA, but I'm still illiterate (and lacking design tools) > in VHDL! > > Glenn Little pointed out that the DS1820 is an obsolete part, now replaced > by the 18S20. Yep -- I just used the "1820" name to describe the generic > device type. When you look at the photo, you will see the holes for the > 18S20 indicated; the DC power and RJ11 1-wire LAN connects thru a > single-piece Hirose connector mounted on the PCB (although for right now, > power for the unit under test is coming thru the red/blk twisted pair). This > was included because >>THE<< principal effect on xtal oscillators comes from > their temperature environment. As the "test pod" is cycled, I wanted to be > able to follow the temperature of the oscillator can. I've also been using > the DS1920 iButton version of the 1820, and the DS1921 temperature logging > iButton is really a neat tool. > > 73, Tom > > --- > You are currently subscribed to tacgps as: BPOWELL@INTREX.NET > To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 31 09:05:22 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id JAA04038 for ; Fri, 31 Aug 2001 09:05:20 -0500 (CDT) Message-ID: Date: Fri, 31 Aug 2001 16:04:54 +0200 From: Dietmar Grossmann X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=iso-8859-2 Content-Transfer-Encoding: 8bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B8F9986.2B39C6B4@gmx.de> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom, IŽd be interested in two PCBs with MiniCircuit parts to help reach the minimum order, but kits would also be welcome. Thanks for the offering. Dietmar Grossmann, DJ4RX --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 31 11:01:24 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id LAA10924 for ; Fri, 31 Aug 2001 11:01:18 -0500 (CDT) Message-ID: Date: Fri, 31 Aug 2001 08:59:56 -0700 From: Dan Hinz X-Accept-Language: en MIME-Version: 1.0 To: "TAPR Special Interest Group" Subject: [tacgps] Re: 5/10 MHz => 1PPS PCBs. Interest? References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: <3B8FB47C.CFA0C942@ieee.org> Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom- I'd be interested in a single board and teh minicircuits parts. Thanks es 73, Dan - W6LSN --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org From bounce-tacgps-6754@lists.tapr.org Fri Aug 31 12:10:21 2001 Received: from lists.tapr.org (lists.tapr.org [204.17.217.24]) by tapr.org (8.9.3/8.9.3/1.13) with SMTP id MAA17007 for ; Fri, 31 Aug 2001 12:10:19 -0500 (CDT) Message-ID: From: jim_johnson@agilent.com To: "TAPR Special Interest Group" Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? Date: Fri, 31 Aug 2001 10:09:39 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" List-Unsubscribe: List-Software: Lyris Server version 3.0 List-Subscribe: List-Owner: X-List-Host: Tucson Amateur Packet Radio Reply-To: "TAPR Special Interest Group" X-Message-Id: Sender: bounce-tacgps-6754@lists.tapr.org Precedence: bulk Hi Tom, I didn't want to bother the list with my question but I can't find a personal email address for you. I'm wondering about the "optimum combiner" you mention below. What characteristic(s) are you trying to optimize? What would be the downside of just buying a combiner/splitter out of a catalog from a vendor? Thanks, Jim, W6SC Agilent Labs Palo Alto, CA jim_johnson@agilent.com > -----Original Message----- > From: Dr. Tom Clark [mailto:tac@clark.net] > Sent: Thursday, August 30, 2001 8:58 PM > To: TAPR Special Interest Group > Subject: [tacgps] RE: 5/10 MHz => 1PPS PCBs. Interest? > > > At Syntonics, I have been working on developing techniques to array N > oscillators to try to extract a sqrt(N) performance > improvement as well as > improved reliability. To try to design the optimum combiner, it became > obvious that we needed a good statistical characterization of > just what is > noisy in various oscillators and what effects performance. > --- You are currently subscribed to tacgps as: lyris.tacgps@tapr.org To unsubscribe send a blank email to leave-tacgps-6754G@lists.tapr.org