Re: [time-nuts] No GPS satellites
Hi All of these older rack mount “GPSDO” products had a fairly long lifespan compared to the advances in GPS receivers. When some / most of them first came out, the only practical /proven way to do timing off GPS was with a downconverter. Without things like serial numbers / date codes it’s tough to figure out if this sample of box A has anything at all to do with another sample of the same box. On top of that, these are very low volume products compared to normal HP or Fluke test gear. It’s unlikely that anybody has a database that tells what is what simply from the serial numbers or date codes. I’d bet that many of them were built to order and rarely in groups larger than a few dozen. Bob On Feb 26, 2015, at 8:19 PM, paul swed paulsw...@gmail.com wrote: Boy I ran out to mr google and did a search and now I am wondering if some versions of the xl-dc just used a plain old GPS antenna. It sure looks like that could be the case. The manual does say down converter. Maybe it changed over time. Regards Paul WB8TSL On Thu, Feb 26, 2015 at 8:15 PM, paul swed paulsw...@gmail.com wrote: A fellow time-nut shared the manual for the xl-dc and I downloaded it. It clearly states that it has a down converter. That was very typical of these generation receivers. As examples the Odetics and Austrons. It allowed for very short antenna runs or virtually 0 length antenna runs and losses. The DC468 goes used the same trick. Almost always the receivers show up without the dowconverter because those stay on the roof. Without the down converter the units useless. I have been lucky in some exploits to use odetics down converters with the austron and the another approach using older styles semi-integrated receivers to fake it. So if you want to experiment there is hope. Though it seems each receivers a bit different.The older Truetime manuals were pretty good with schematics and explanations. Unfortunately it looks like the new manual has little to go on. Regards Paul WB8TSL On Thu, Feb 26, 2015 at 4:46 PM, Bill Hawkins b...@iaxs.net wrote: Doesn't the DC in the model number mean down conversion or something like that? Seems to me it did in the obsolete 468-DC GOES time receivers, which had to down convert to about 1.8 MHz. Also, the down conversion was more than a simple local oscillator and mixer. You had to have their antenna to make it work, as the mixer was in the base of the antenna. Bill Hawkins -Original Message- From: Tim Shoppa Sent: Wednesday, February 25, 2015 7:56 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] No GPS satellites Yes, the XL-DC and other Truetime models had as an option for long cable runs, a downconverter in the antenna. I don't know how to tell the difference from part number, but I know the truetimes my employer uses all have the downconverter option and the option is very common. Tim N3QE ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Boy I ran out to mr google and did a search and now I am wondering if some versions of the xl-dc just used a plain old GPS antenna. It sure looks like that could be the case. The manual does say down converter. Maybe it changed over time. Regards Paul WB8TSL On Thu, Feb 26, 2015 at 8:15 PM, paul swed paulsw...@gmail.com wrote: A fellow time-nut shared the manual for the xl-dc and I downloaded it. It clearly states that it has a down converter. That was very typical of these generation receivers. As examples the Odetics and Austrons. It allowed for very short antenna runs or virtually 0 length antenna runs and losses. The DC468 goes used the same trick. Almost always the receivers show up without the dowconverter because those stay on the roof. Without the down converter the units useless. I have been lucky in some exploits to use odetics down converters with the austron and the another approach using older styles semi-integrated receivers to fake it. So if you want to experiment there is hope. Though it seems each receivers a bit different.The older Truetime manuals were pretty good with schematics and explanations. Unfortunately it looks like the new manual has little to go on. Regards Paul WB8TSL On Thu, Feb 26, 2015 at 4:46 PM, Bill Hawkins b...@iaxs.net wrote: Doesn't the DC in the model number mean down conversion or something like that? Seems to me it did in the obsolete 468-DC GOES time receivers, which had to down convert to about 1.8 MHz. Also, the down conversion was more than a simple local oscillator and mixer. You had to have their antenna to make it work, as the mixer was in the base of the antenna. Bill Hawkins -Original Message- From: Tim Shoppa Sent: Wednesday, February 25, 2015 7:56 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] No GPS satellites Yes, the XL-DC and other Truetime models had as an option for long cable runs, a downconverter in the antenna. I don't know how to tell the difference from part number, but I know the truetimes my employer uses all have the downconverter option and the option is very common. Tim N3QE ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Doesn't the DC in the model number mean down conversion or something like that? Seems to me it did in the obsolete 468-DC GOES time receivers, which had to down convert to about 1.8 MHz. Also, the down conversion was more than a simple local oscillator and mixer. You had to have their antenna to make it work, as the mixer was in the base of the antenna. Bill Hawkins -Original Message- From: Tim Shoppa Sent: Wednesday, February 25, 2015 7:56 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] No GPS satellites Yes, the XL-DC and other Truetime models had as an option for long cable runs, a downconverter in the antenna. I don't know how to tell the difference from part number, but I know the truetimes my employer uses all have the downconverter option and the option is very common. Tim N3QE ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Just a heads up as I stumbled on an interesting XL-DC plugin module for sale on ebay while looking for info for Doug. TrueTime Symmetricom XL-DC FTM-III AC Line Frequency Measurement Time Monitor Unfortunately I don’t have an XL-DC, but it looks just just the tick for a time nut who has. Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin Le 25 févr. 2015 à 20:35, Doug Ronald d...@dougronald.com a écrit : I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Mike, That's the same card I used for the 40-day run: http://leapsecond.com/pages/mains/ It's robust and professional (used in the electric grid industry) and nice if you already have a working XL-DC but most of us now use a $1 microcontroller or DCD pin and NTP to track mains phase frequency. /tvb On Feb 26, 2015, at 2:27 AM, Mike Cook michael.c...@sfr.fr wrote: Just a heads up as I stumbled on an interesting XL-DC plugin module for sale on ebay while looking for info for Doug. TrueTime Symmetricom XL-DC FTM-III AC Line Frequency Measurement Time Monitor Unfortunately I don’t have an XL-DC, but it looks just just the tick for a time nut who has. Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin Le 25 févr. 2015 à 20:35, Doug Ronald d...@dougronald.com a écrit : I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Since your antennas have a lot of gain I assume they are active and require a DC voltage to the LNA. Does the XL-DC provide that voltage (sometime you have to select active or passive antenna)? Michael / K7HIL On Wed, Feb 25, 2015 at 12:35 PM, Doug Ronald d...@dougronald.com wrote: I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] No GPS satellites
Yes, the XL-DC and other Truetime models had as an option for long cable runs, a downconverter in the antenna. I don't know how to tell the difference from part number, but I know the truetimes my employer uses all have the downconverter option and the option is very common. Tim N3QE On Wednesday, February 25, 2015, Doug Ronald d...@dougronald.com javascript:_e(%7B%7D,'cvml','d...@dougronald.com'); wrote: I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
The XL-DC Can use either a normal L1 or Down converter Antenna according to the manual. http://www.prostudioconnection.net/1112/xl-dc-manual.pdf If your antenna works with the Lucent then it will be a normal one. Does your XL-DC have any option codes? Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin Le 25 févr. 2015 à 20:35, Doug Ronald d...@dougronald.com a écrit : I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] No GPS satellites
Yes, the TrueTime unit needs its antenna/downconverter to work. Other GPSDOs, like the Meinberg units GPS-SA used in the Rohde Schwarz ED167MP have this arrangement. On Wed, Feb 25, 2015 at 8:35 PM, Doug Ronald d...@dougronald.com wrote: I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] No GPS satellites
I'm hoping someone can shed some light on my problem receiving any GPS satellites. I have two TrueTime GPS Time Frequency Receivers, Model XL-DC. One has a regular crystal oscillator, and the other one has a rubidium oscillator. I have two outdoor GPS antennas with internal LNAs, one a 28 dB gain unit, and the other a 40 dB unit. When either antenna is connected to my Lucent KS-24361, it locks right up and tracks up to 8 satellites. When either of the antennas is connected to the XL-DCs, they just sit there and status : Looking for GPS satellites. In the Alarm menu of either XL-DC there is an alarm for Antenna. Both units say OK and if I disconnect the antenna they both logically say Open. So, what is the problem? I can't believe I don't have enough signal, after the Lucent locks-up right away. Is it possible the TrueTime sanctioned antenna has a down converter in it, perhaps placing the GPS signal from L-band to some lower frequency? I would appreciate any info the group might have... -Doug Ronald W6DSR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Jeffrey Pawlan wrote: On Thu, 25 Mar 2010, Magnus Danielson wrote: Dear Raj, Oh, sorry, needed a few extra. Wanted to recover the rubidiums and put some on Ebay. I gave a lecture about antennas for operation on 1296MHz last week and mentioned that my vacuum tube power abplifier was damaged by a gassy tube. I want to replace it with a solid state amp. One of the engineers present suggested that I find a GPS satellite on the surplus market and pull the the power amplifier out of it. He obviously did not know that satellites , even spares, do not show up on the surplus market. Things like that DO show up as surplus but I wouldn't call it a market. When we excess things at JPL (and that includes spare flight hardware), it goes on a list, and other NASA centers, and then gov't agencies, and then universities/colleges/educational institutions get a crack at it. Finally, it will get scrapped. There is also the ITAR and export controls issue. (an interesting question I'll have to ask... if you have a rad hard widget for a spacecraft (clearly ITAR), and you surplus it in a way that makes it impossible to know it's Class S, is it still controlled..) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
For sure. There was a surplus store in Santa Maria that got bits of space qualified stuff from Vandenberg AFB, and, of course, CH in Pasadena. I got a bunch of things from both, including a number os qual'd spacecraft transmitters and sensors and some Apollo and Saturn items. Kewl stuff! -John = Things like that DO show up as surplus but I wouldn't call it a market. When we excess things at JPL (and that includes spare flight hardware), it goes on a list, and other NASA centers, and then gov't agencies, and then universities/colleges/educational institutions get a crack at it. Finally, it will get scrapped. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Missing GPS satellites
Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Hi Is there a very large bird making a nest on top of your antenna? I *have* had that problem my self. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Raj Sent: Thursday, March 25, 2010 8:04 AM To: Time Nuts Subject: [time-nuts] Missing GPS satellites Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
They wouldn't really do that would they? ;-) On Thu, Mar 25, 2010 at 12:36 PM, J. Forster j...@quik.com wrote: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Dear Raj, Raj wrote: Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Oh, sorry, needed a few extra. Wanted to recover the rubidiums and put some on Ebay. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
News story a few days back that in parts of Afghanistan wireless which has 99% vs 1% wired phones would go out every nite, on orders of the Taleban, to prevent civilians from reporting activity to Coalition forces. Think the wireless networks would last a little longer than a few hours without timing info but you never know , does your cell phone still work? Stanley - Original Message From: paul swed paulsw...@gmail.com To: j...@quik.com; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thu, March 25, 2010 12:17:10 PM Subject: Re: [time-nuts] Missing GPS satellites They wouldn't really do that would they? ;-) On Thu, Mar 25, 2010 at 12:36 PM, J. Forster j...@quik.com wrote: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
On Thu, 25 Mar 2010, Magnus Danielson wrote: Dear Raj, Oh, sorry, needed a few extra. Wanted to recover the rubidiums and put some on Ebay. I gave a lecture about antennas for operation on 1296MHz last week and mentioned that my vacuum tube power abplifier was damaged by a gassy tube. I want to replace it with a solid state amp. One of the engineers present suggested that I find a GPS satellite on the surplus market and pull the the power amplifier out of it. He obviously did not know that satellites , even spares, do not show up on the surplus market. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
I do not believe that is the case as the terminals I work on, used mostly by the Army the Marines, use relatively cheap GPSs in them and we have them all over, Iraq, Afghanistan, Kuwait, etc.. 73 - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ 07731 732-886-5960 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster Sent: Thursday, March 25, 2010 12:37 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Missing GPS satellites It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Link to new story: http://www.cbsnews.com/8301-503543_162-20001083-503543.html http://online.wsj.com/article/SB20001424052748704117304575137541465235972.html Stanley ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. -John = I do not believe that is the case as the terminals I work on, used mostly by the Army the Marines, use relatively cheap GPSs in them and we have them all over, Iraq, Afghanistan, Kuwait, etc.. 73 - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ 07731 732-886-5960 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster Sent: Thursday, March 25, 2010 12:37 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Missing GPS satellites It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
J. Forster wrote: From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. The preferred method of controlling the access to GPS within a region is GPS jammers, and the full set of efforts being spent on strengthening the allied forces availability to signal is to ensure ability to survive from jamming signal, which includes removing need for C/A locking prior to Y-code lock with direct lock methods, transfer of time, solutions and ephemeris data, and eventually means to direct additional power towards the area and the improved M-code. Turning of the C/A code of a satellite will effect the 1/3 of the earth area that it sees, and for that to be effective in a certain area, you need to do that to 6-8 sats to turn it off, and that will significantly reduce the GPS availability for so large geographical areas that things they want to work will run closer to failure. So no, turning of C/A code is not what they want to do it. They can, but they want to avoid it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Hi I still think it's a bird on the antenna. Bob On Mar 25, 2010, at 7:11 PM, Magnus Danielson wrote: J. Forster wrote: From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. The preferred method of controlling the access to GPS within a region is GPS jammers, and the full set of efforts being spent on strengthening the allied forces availability to signal is to ensure ability to survive from jamming signal, which includes removing need for C/A locking prior to Y-code lock with direct lock methods, transfer of time, solutions and ephemeris data, and eventually means to direct additional power towards the area and the improved M-code. Turning of the C/A code of a satellite will effect the 1/3 of the earth area that it sees, and for that to be effective in a certain area, you need to do that to 6-8 sats to turn it off, and that will significantly reduce the GPS availability for so large geographical areas that things they want to work will run closer to failure. So no, turning of C/A code is not what they want to do it. They can, but they want to avoid it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
What's your latitude Raj? Rob K -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: 25 March 2010 11:15 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Missing GPS satellites Hi I still think it's a bird on the antenna. Bob On Mar 25, 2010, at 7:11 PM, Magnus Danielson wrote: J. Forster wrote: From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. The preferred method of controlling the access to GPS within a region is GPS jammers, and the full set of efforts being spent on strengthening the allied forces availability to signal is to ensure ability to survive from jamming signal, which includes removing need for C/A locking prior to Y-code lock with direct lock methods, transfer of time, solutions and ephemeris data, and eventually means to direct additional power towards the area and the improved M-code. Turning of the C/A code of a satellite will effect the 1/3 of the earth area that it sees, and for that to be effective in a certain area, you need to do that to 6-8 sats to turn it off, and that will significantly reduce the GPS availability for so large geographical areas that things they want to work will run closer to failure. So no, turning of C/A code is not what they want to do it. They can, but they want to avoid it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
I do not think so. If that were the case then the satellite terminals would be considered as classified and handling would be a lot different. Certainly, these terminals are compatible with SAASM, but of course they are not in use. Most use simple Trimble, Brandywine, Motorola receiver boards, even boards from our own Said Jackson of Jackson Labs, and we have about a thousand of these in theater. Regards - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ 07731 732-886-5960 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster Sent: Thursday, March 25, 2010 6:27 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Missing GPS satellites From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. -John = I do not believe that is the case as the terminals I work on, used mostly by the Army the Marines, use relatively cheap GPSs in them and we have them all over, Iraq, Afghanistan, Kuwait, etc.. 73 - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ 07731 732-886-5960 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster Sent: Thursday, March 25, 2010 12:37 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Missing GPS satellites It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. -John == Ahem!, time-nuts. Please release all GPS satellites you are holding up on the other side of the world. I don't seem to have any over my head over Asia. I wonder what happens to those guided missiles that depend of GPS or those in vehicles looking for directions ? Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites (Mike Feher)
Just went to a farm meeting on GPS farm machinery control. At least one equipment mfgr commented that they use GPS but have Glosnoss ability for the times that GPS is limited here in the states. N0UU ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Missing GPS satellites
That is DOP is too high... dilution of precision... the sats are in a poor position for doing fixes. You have probably put the receiver into a 2D or 3D fix mode (not overdetermined clock mode). From the S)urvey menu, select receiver mode 5. _ Hotmail: Trusted email with Microsoft’s powerful SPAM protection. http://clk.atdmt.com/GBL/go/210850552/direct/01/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
Thanks Mark, I was fiddling around with 2D/3D when I saw that error message. I experimented in comparing two GPSDOs, one with full sky and one with limited visibility. All settings kept identical. There was very slow phase difference noted within a narrow range. The exception was when there were not enough sats then I saw sudden fast changes. That is DOP is too high... dilution of precision... the sats are in a poor position for doing fixes. You have probably put the receiver into a 2D or 3D fix mode (not overdetermined clock mode). From the S)urvey menu, select receiver mode 5. _ Hotmail: Trusted email with Microsofts powerful SPAM protection. http://clk.atdmt.com/GBL/go/210850552/direct/01/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Missing GPS satellites
I'm at 43S, 172E and the minimum number of birds I'm seeing in the middle of the days is 4 with a maximum of 12 each night. No sign of a let up here, guano all over the place :) Steve Rooke On 26/03/2010, Raj vu2...@gmail.com wrote: Rob, I am 13N 77E approx. Bob, I checked everytime and no birds. I setup two GPSDOs with seperate antennas and both went to hold over. Its been happening ever day at some times. Even I get the error on this page http://www.n2yo.com/whats-up/?c=20 Lady heather says the doppler is high or something and satellites not usable. Sometimes there are 3 sats overhead and none usable! At 26-03-10, you wrote: What's your latitude Raj? Rob K -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: 25 March 2010 11:15 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Missing GPS satellites Hi I still think it's a bird on the antenna. Bob On Mar 25, 2010, at 7:11 PM, Magnus Danielson wrote: J. Forster wrote: From an unnamed, but VERY credible source: It might be that the DoD is turning the civilian signals off in combat areas to deny GPS to the Taliban and others. Quite possible. This countermeasure was discussed more than ten years ago. It is possible to turn of the civilian signals -- or to leave then on but _jam_ them within a selected area -- without interfering with US military use of the satellites. A modern military does not need the C/ A code to acquire lock on a satellite. It can acquire the encrypted P code directly. The preferred method of controlling the access to GPS within a region is GPS jammers, and the full set of efforts being spent on strengthening the allied forces availability to signal is to ensure ability to survive from jamming signal, which includes removing need for C/A locking prior to Y-code lock with direct lock methods, transfer of time, solutions and ephemeris data, and eventually means to direct additional power towards the area and the improved M-code. Turning of the C/A code of a satellite will effect the 1/3 of the earth area that it sees, and for that to be effective in a certain area, you need to do that to 6-8 sats to turn it off, and that will significantly reduce the GPS availability for so large geographical areas that things they want to work will run closer to failure. So no, turning of C/A code is not what they want to do it. They can, but they want to avoid it. Cheers, Magnus -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Steve Rooke - ZL3TUV G8KVD A man with one clock knows what time it is; A man with two clocks is never quite sure. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
