Re: [time-nuts] LTE Lite time error
Just to let you know that I received my replacement NS-T receiver and verified that that problem is fixed. ___ 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] LTE Lite time error
NAVCEN issued an alert regarding receiver errors in handling the current pending leap second data like has occurred with the Skytraq receiver. Several brands/models were affected. I have not seen the original alert, but here is an article summarizing: http://www.insidegnss.com/node/4398 Keith Keith On Mon, Feb 2, 2015 at 9:35 AM, Keith Loiselle keith.loise...@gmail.com wrote: We have received some additional information from Skytraq regarding the leap second error: The faulty version firmware indicates leap seconds (17) from now to June 16th (two weeks before June 30th). During June 16th ~ June 30th, leap second will recover to 16 and change properly to 17 on June 30th midnight. For future leap seconds, if the leap second change is still broadcasted ahead of time for more than 2 weeks, it'll still have this problem for coming leap seconds. Keith Keith On Wed, Jan 28, 2015 at 9:27 AM, Tom Van Baak t...@leapsecond.com wrote: I have verified the Skytraq claim on my stand alone NS-T. Tue Jan 27 06:52:06 UTC 2015 $GPGGA,065206.000,4847.3506 Hi Mike, Please use more precise timestamps so your results can be believed. In general it's not adequate to use one second unix time stamps to identify a possible one second NMEA error. Instead try using something like dateu.c (www.leapsecond.com/tools/) to output microsecond timestamps. /tvb ___ 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] LTE Lite time error
We have received some additional information from Skytraq regarding the leap second error: The faulty version firmware indicates leap seconds (17) from now to June 16th (two weeks before June 30th). During June 16th ~ June 30th, leap second will recover to 16 and change properly to 17 on June 30th midnight. For future leap seconds, if the leap second change is still broadcasted ahead of time for more than 2 weeks, it'll still have this problem for coming leap seconds. Keith Keith On Wed, Jan 28, 2015 at 9:27 AM, Tom Van Baak t...@leapsecond.com wrote: I have verified the Skytraq claim on my stand alone NS-T. Tue Jan 27 06:52:06 UTC 2015 $GPGGA,065206.000,4847.3506 Hi Mike, Please use more precise timestamps so your results can be believed. In general it's not adequate to use one second unix time stamps to identify a possible one second NMEA error. Instead try using something like dateu.c (www.leapsecond.com/tools/) to output microsecond timestamps. /tvb ___ 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] LTE Lite time error
I have verified the Skytraq claim on my stand alone NS-T. Tue Jan 27 06:52:06 UTC 2015 $GPGGA,065206.000,4847.3506,N,00216.3005,E,1,06,1.3,191.0,M,47.0,M,,*59 Tue Jan 27 06:52:06 UTC 2015 $GPGLL,4847.3506,N,00216.3005,E,065206.000,A,A*52 Tue Jan 27 06:52:06 UTC 2015 $GPGSA,A,3,04,01,22,28,27,11,,,2.1,1.3,1.7*3F Tue Jan 27 06:52:06 UTC 2015 $GPGSV,2,1,07,04,83,016,40,11,77,287,36,01,57,288,47,28,29,299,42*7E Tue Jan 27 06:52:06 UTC 2015 $GPGSV,2,2,07,03,28,223,09,22,25,056,41,27,21,149,26*42 Tue Jan 27 06:52:06 UTC 2015 $GPRMC,065206.000,A,4847.3506,N,00216.3005,E,000.0,000.0,270115,,,A*65 Tue Jan 27 06:52:06 UTC 2015 $GPVTG,000.0,T,,M,000.0,N,000.0,K,A*0D Tue Jan 27 06:52:06 UTC 2015 $GPZDA,065206.000,27,01,2015,00,00*53 Using the GNSS gui, Query Timing, get a NAK. Monitoring 1PPS gets blank. When booting from Flash, the quantization error of +/-6ns was verifiable both with Monitor Timing on the GUI and on my scope triggered from my T-Bolt.. When booting from ROM it doesn’t seem to be any worse than +/-10ns . I would think that the lower quantization error would enable better phase locking in a GPSDO, especially with a long time constant, which is why I bought the device in the first place. So anyone with an LTE-Lite may just prefer to not use the NMEA stream until a new firmware becomes available, rather than use the WA. It would be of interest to others to see what booting from ROM makes in practice with the LTE-Lite. One observation that I will make is that TTFF is MUCH faster when booting from ROM, and the device is MUCH more sensitive. I can pull in twice the number of SATS when booting from ROM. I am getting HDOP figure 1…wow! The reason why my receiver is not glued to a PRS10 at the moment is that I kept losing 3D Position fix according to the GUI when booted from Flash, even though when in Static mode the 1PPS looked good. 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 27 janv. 2015 à 02:29, Bill Beam wb...@gci.net a écrit : Be careful with 'eyeball data'. GPS receiver does not generate NMEA time data and the leading edge of PPS at the same time. Programs like Tac32 (totally accurate clock) and Lady Heather increment the time display at the leading edge of PPS with a value 1 second greater than the previous NMEA data time. I am able to run multiple GPS receivers into multiple computers running Tac32. The LTE-lite displays one second earlier than all the others. Prior to the announcement of Leap Second Pending in the GPS data stream the LTE-lite agreed with all other units. Now it does not. On Mon, 26 Jan 2015 22:59:36 +0100, Mike Cook wrote: Yes there is certainly an error here: With my timing module I was just eyeballing the output on a windows platform , comparing GUI data. I have just linked the module up to a BeagleBone Black syncG�d with NTP and this is the NMEA msg log: root@bb3:/home/mike/serial-ports# while read GGA; do echo `date` $GGA; done /dev/ttyO4 Mon Jan 26 21:51:07 UTC 2015 $GPGGA,215106.000,4847.3526,N,00216.3005,E,1,04,2.8,192.8,M,47.0,M,,*5C Mon Jan 26 21:51:07 UTC 2015 $GPGLL,4847.3526,N,00216.3005,E,215106.000,A,A*56 Mon Jan 26 21:51:07 UTC 2015 $GPGSA,A,3,25,12,06,31,3.0,2.8,1.0*3A Mon Jan 26 21:51:07 UTC 2015 $GPRMC,215106.000,A,4847.3526,N,00216.3005,E,000.0,173.5,260115,,,A*60 Mon Jan 26 21:51:07 UTC 2015 $GPVTG,173.5,T,,M,000.0,N,000.0,K,A*0D Mon Jan 26 21:51:07 UTC 2015 $GPZDA,215106.000,26,01,2015,00,00*54 Mon Jan 26 21:51:07 UTC 2015 $PSTI,00,2,0,4.6,,*30 snip The time data is all a second late so they appear to have a serious issue. Le 26 janv. 2015 +� 02:47, Bill Beam wb...@gci.net a +�crit : snip Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. snip Bill Beam NL7F ___ 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] LTE Lite time error
I have verified the Skytraq claim on my stand alone NS-T. Tue Jan 27 06:52:06 UTC 2015 $GPGGA,065206.000,4847.3506 Hi Mike, Please use more precise timestamps so your results can be believed. In general it's not adequate to use one second unix time stamps to identify a possible one second NMEA error. Instead try using something like dateu.c (www.leapsecond.com/tools/) to output microsecond timestamps. /tvb ___ 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] LTE Lite time error
Skytraq has provided updated firmware that corrects the 1 second offset. For those who have not already, please contact us off list for return instructions to have your unit updated. Thank you for your patience with this issue. According to Skytraq the error was introduced when code was added based on a customer request. Keith Keith On Wed, Jan 28, 2015 at 9:27 AM, Tom Van Baak t...@leapsecond.com wrote: I have verified the Skytraq claim on my stand alone NS-T. Tue Jan 27 06:52:06 UTC 2015 $GPGGA,065206.000,4847.3506 Hi Mike, Please use more precise timestamps so your results can be believed. In general it's not adequate to use one second unix time stamps to identify a possible one second NMEA error. Instead try using something like dateu.c (www.leapsecond.com/tools/) to output microsecond timestamps. /tvb ___ 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] LTE Lite time error
Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. I am awaiting reply from JL. This is not good for an eBay sniper Bill, NL7F On Sun, 25 Jan 2015 12:12:55 -0800, Tom Van Baak wrote: Hi Paul, Odd, my LTE-Lite appears spot on. Let's take this off-list and see what's going on. If anyone else has been logging SkyTraq NMEA or binary from the LTE-Lite let us know. Bill Beam NL7F ___ 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] LTE Lite time error
We have confirmed this issue with the Skytraq firmware on the LTE-Lite and are working with Skytraq to obtain a firmware update. I will post again when a firmware update is available. Keith Keith On Sun, Jan 25, 2015 at 5:47 PM, Bill Beam wb...@gci.net wrote: Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. I am awaiting reply from JL. This is not good for an eBay sniper Bill, NL7F On Sun, 25 Jan 2015 12:12:55 -0800, Tom Van Baak wrote: Hi Paul, Odd, my LTE-Lite appears spot on. Let's take this off-list and see what's going on. If anyone else has been logging SkyTraq NMEA or binary from the LTE-Lite let us know. Bill Beam NL7F ___ 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] LTE Lite time error
Skytraq has also confirmed the issue and is working on a firmware update. Updating the Skytraq firmware on the LTE-Lite Eval Board requires the unit be returned to Jackson Labs for reprogramming. We will update the Skytraq firmware on units at no charge if units are returned to us. Please contact us off list to make arrangements for returns. Also, the ROM firmware in the Skytraq does not exhibit this issue, so selecting the ROM boot with a jumper between pins 1 and 2 of J3 is a work-around. When making the J3 connection, be sure to remove power to the board to avoid corrupting the flash. The LTE-Lite will operate in a mobile mode without sawtooth correction when the Skytraq is booted from ROM. Thanks, Keith Keith On Mon, Jan 26, 2015 at 10:43 AM, Keith Loiselle keith.loise...@gmail.com wrote: We have confirmed this issue with the Skytraq firmware on the LTE-Lite and are working with Skytraq to obtain a firmware update. I will post again when a firmware update is available. Keith Keith On Sun, Jan 25, 2015 at 5:47 PM, Bill Beam wb...@gci.net wrote: Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. I am awaiting reply from JL. This is not good for an eBay sniper Bill, NL7F On Sun, 25 Jan 2015 12:12:55 -0800, Tom Van Baak wrote: Hi Paul, Odd, my LTE-Lite appears spot on. Let's take this off-list and see what's going on. If anyone else has been logging SkyTraq NMEA or binary from the LTE-Lite let us know. Bill Beam NL7F ___ 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] LTE Lite time error
Be careful with 'eyeball data'. GPS receiver does not generate NMEA time data and the leading edge of PPS at the same time. Programs like Tac32 (totally accurate clock) and Lady Heather increment the time display at the leading edge of PPS with a value 1 second greater than the previous NMEA data time. I am able to run multiple GPS receivers into multiple computers running Tac32. The LTE-lite displays one second earlier than all the others. Prior to the announcement of Leap Second Pending in the GPS data stream the LTE-lite agreed with all other units. Now it does not. On Mon, 26 Jan 2015 22:59:36 +0100, Mike Cook wrote: Yes there is certainly an error here: With my timing module I was just eyeballing the output on a windows platform , comparing GUI data. I have just linked the module up to a BeagleBone Black syncGd with NTP and this is the NMEA msg log: root@bb3:/home/mike/serial-ports# while read GGA; do echo `date` $GGA; done /dev/ttyO4 Mon Jan 26 21:51:07 UTC 2015 $GPGGA,215106.000,4847.3526,N,00216.3005,E,1,04,2.8,192.8,M,47.0,M,,*5C Mon Jan 26 21:51:07 UTC 2015 $GPGLL,4847.3526,N,00216.3005,E,215106.000,A,A*56 Mon Jan 26 21:51:07 UTC 2015 $GPGSA,A,3,25,12,06,31,3.0,2.8,1.0*3A Mon Jan 26 21:51:07 UTC 2015 $GPRMC,215106.000,A,4847.3526,N,00216.3005,E,000.0,173.5,260115,,,A*60 Mon Jan 26 21:51:07 UTC 2015 $GPVTG,173.5,T,,M,000.0,N,000.0,K,A*0D Mon Jan 26 21:51:07 UTC 2015 $GPZDA,215106.000,26,01,2015,00,00*54 Mon Jan 26 21:51:07 UTC 2015 $PSTI,00,2,0,4.6,,*30 snip The time data is all a second late so they appear to have a serious issue. Le 26 janv. 2015 + 02:47, Bill Beam wb...@gci.net a +ªcrit : snip Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. snip Bill Beam NL7F ___ 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] LTE Lite time error
Yes there is certainly an error here: With my timing module I was just eyeballing the output on a windows platform , comparing GUI data. I have just linked the module up to a BeagleBone Black sync’d with NTP and this is the NMEA msg log: root@bb3:/home/mike/serial-ports# while read GGA; do echo `date` $GGA; done /dev/ttyO4 Mon Jan 26 21:51:07 UTC 2015 $GPGGA,215106.000,4847.3526,N,00216.3005,E,1,04,2.8,192.8,M,47.0,M,,*5C Mon Jan 26 21:51:07 UTC 2015 $GPGLL,4847.3526,N,00216.3005,E,215106.000,A,A*56 Mon Jan 26 21:51:07 UTC 2015 $GPGSA,A,3,25,12,06,31,3.0,2.8,1.0*3A Mon Jan 26 21:51:07 UTC 2015 $GPRMC,215106.000,A,4847.3526,N,00216.3005,E,000.0,173.5,260115,,,A*60 Mon Jan 26 21:51:07 UTC 2015 $GPVTG,173.5,T,,M,000.0,N,000.0,K,A*0D Mon Jan 26 21:51:07 UTC 2015 $GPZDA,215106.000,26,01,2015,00,00*54 Mon Jan 26 21:51:07 UTC 2015 $PSTI,00,2,0,4.6,,*30 Mon Jan 26 21:51:08 UTC 2015 $GPGGA,215107.000,4847.3526,N,00216.3005,E,1,04,2.8,192.8,M,47.0,M,,*5D Mon Jan 26 21:51:08 UTC 2015 $GPGLL,4847.3526,N,00216.3005,E,215107.000,A,A*57 Mon Jan 26 21:51:08 UTC 2015 $GPGSA,A,3,25,12,06,31,3.0,2.8,1.0*3A Mon Jan 26 21:51:08 UTC 2015 $GPGSV,3,1,10,25,73,294,42,12,59,063,44,14,45,264,20,29,41,196,25*7B Mon Jan 26 21:51:08 UTC 2015 $GPGSV,3,2,10,24,34,136,13,02,28,091,21,31,22,306,34,06,19,047,37*74 Mon Jan 26 21:51:08 UTC 2015 $GPGSV,3,3,10,32,03,310,,03,01,347,*7A Mon Jan 26 21:51:08 UTC 2015 $GPRMC,215107.000,A,4847.3526,N,00216.3005,E,000.0,173.5,260115,,,A*61 Mon Jan 26 21:51:08 UTC 2015 $GPVTG,173.5,T,,M,000.0,N,000.0,K,A*0D Mon Jan 26 21:51:08 UTC 2015 $GPZDA,215107.000,26,01,2015,00,00*55 Mon Jan 26 21:51:08 UTC 2015 $PSTI,00,2,0,-3.9,,*15 The time data is all a second late so they appear to have a serious issue. I module I have is the NS-T from NavSpark, so I will get on to them to see if they have a fix. Updates later. 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 26 janv. 2015 à 02:47, Bill Beam wb...@gci.net a écrit : Odd indeed. My LTE-lite is one second late, appears to have already added the pending leap second. I can compare with four other GPS timeing receivers using time pulse on DCD line. The NMEA data reports in error. I am awaiting reply from JL. This is not good for an eBay sniper Bill, NL7F On Sun, 25 Jan 2015 12:12:55 -0800, Tom Van Baak wrote: Hi Paul, Odd, my LTE-Lite appears spot on. Let's take this off-list and see what's going on. If anyone else has been logging SkyTraq NMEA or binary from the LTE-Lite let us know. Bill Beam NL7F ___ 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] LTE Lite time error
Hi Paul, Odd, my LTE-Lite appears spot on. Let's take this off-list and see what's going on. If anyone else has been logging SkyTraq NMEA or binary from the LTE-Lite let us know. Thanks, /tvb $SkyTraq,Venus8 $Kernel,v2.0.2,1C92,1426,6005,I,16.367667MHz $ver,010827,rev,130221 - Original Message - From: Paul tic-...@bodosom.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Friday, January 23, 2015 8:58 PM Subject: [time-nuts] LTE Lite time error I see a one second error in the NMEA string from my LTE Lite. It lost a second between 23:33:34 and 23:33:42 21-Jan-2015 UTC. I happened to check because a report of a one second error in some NTP pool servers. Just a heads up -- I'll be following up with JL directly. -- Paul ___ 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] LTE Lite time error
I see a one second error in the NMEA string from my LTE Lite. It lost a second between 23:33:34 and 23:33:42 21-Jan-2015 UTC. I happened to check because a report of a one second error in some NTP pool servers. Just a heads up -- I'll be following up with JL directly. -- Paul ___ 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] LTE-Lite
On 5 Dec 2014 07:05, David J Taylor david-tay...@blueyonder.co.uk wrote: David it always does a survey. Though even while doing that the frequency output is fine after its had a bit to stabilize. I wanted to bring the survey lamp out to a front panel LED however that appeared to be more work and risk then the value. Have you considered to use a light pipe? Hopefully you could get enough light out. Or is all else fails, use a photodiode to detect the light and drive an LED. Dave. ___ 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] LTE-Lite
Have you considered to use a light pipe? Hopefully you could get enough light out. Or is all else fails, use a photodiode to detect the light and drive an LED. Dave. Good suggestion, Dave. Light pipes used to be very popular, but I couldn't find one when I searched a little while back. Perhaps I was using the wrong search terms! I would have thought that Maplin, for example, would have something. David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] LTE-Lite
I think the name light pipe has been supplanted by fiber-optic. -Chuck Harris David J Taylor wrote: Have you considered to use a light pipe? Hopefully you could get enough light out. Or is all else fails, use a photodiode to detect the light and drive an LED. Dave. Good suggestion, Dave. Light pipes used to be very popular, but I couldn't find one when I searched a little while back. Perhaps I was using the wrong search terms! I would have thought that Maplin, for example, would have something. David ___ 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] LTE-Lite
On 5 Dec 2014 13:19, Chuck Harris cfhar...@erols.com wrote: I think the name light pipe has been supplanted by fiber-optic. -Chuck Harris Technically I agree that they have a lot in common. But I think the large devices, which are often not cylindrical, are usually called light pipes. http://uk.mouser.com/Mobile/Optoelectronics/LED-Indication/LED-Light-Pipes/_/N-b1d20 Some light pipes are hollow inside. I think that is stretching the definition of optical fibre. According to Wikipedia, light pipes or light tubes were originally developed by the ancient Egyptians. Some of these things are hollow are more than 1 m in diameter. I would hardly call that an optical fibre. But call them what you fancy (optical fibre, multi more fibre, waveguide, light tube, light pipe. ...) I think such a device might solve the problem getting the LTE Lite's status LEDs onto a box. I don't have an LTE Lite, but given that they are low power devices, where heat generation is undesirable, I suspect that the light output level might be a bit low. In which case a photodiode or similar may be needed. Dave. ___ 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] LTE-Lite
We were talking about remotely viewing light from small things like LED's. I hardly think that telling me about a 1m diameter solar light pipe, or the marvels of ancient Egyptians is relevant. I see two types of devices used for moving light remotely: 1) fiber optic, which is a standardized media, and is available off the shelf, and in any length you want. It isn't all the stuff meant to run data around. 2) custom molded acrylic light pipes, which are, well, custom made devices for the situation at hand. Which of the two do you think is more applicable to the OP's needs? -Chuck Harris Dr. David Kirkby (Kirkby Microwave Ltd) wrote: On 5 Dec 2014 13:19, Chuck Harris cfhar...@erols.com wrote: I think the name light pipe has been supplanted by fiber-optic. -Chuck Harris Technically I agree that they have a lot in common. But I think the large devices, which are often not cylindrical, are usually called light pipes. http://uk.mouser.com/Mobile/Optoelectronics/LED-Indication/LED-Light-Pipes/_/N-b1d20 Some light pipes are hollow inside. I think that is stretching the definition of optical fibre. According to Wikipedia, light pipes or light tubes were originally developed by the ancient Egyptians. Some of these things are hollow are more than 1 m in diameter. I would hardly call that an optical fibre. But call them what you fancy (optical fibre, multi more fibre, waveguide, light tube, light pipe. ...) I think such a device might solve the problem getting the LTE Lite's status LEDs onto a box. I don't have an LTE Lite, but given that they are low power devices, where heat generation is undesirable, I suspect that the light output level might be a bit low. In which case a photodiode or similar may be needed. Dave. ___ 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] LTE-Lite
That is a good suggestion. But I fall into the camp. Not really that important now. At least not to get me to pull it out of the rack. :-) The little LED are pretty bright and I remember some broadcast equipment used light pipes. OK now I am going to get silly but this is time-nuts. I think light pipe and fiber optics are two different terms. Yes they both pass light. But a fiber optic is a precision glass or plastic waveguide. A light pipe is a bulk piece of plastic that is not a wave guide in respect to the accuracy of the walls. Oh I am so doomed now that I said that. Regards Paul WB8TSL On Fri, Dec 5, 2014 at 9:10 AM, Dr. David Kirkby (Kirkby Microwave Ltd) drkir...@kirkbymicrowave.co.uk wrote: On 5 Dec 2014 13:19, Chuck Harris cfhar...@erols.com wrote: I think the name light pipe has been supplanted by fiber-optic. -Chuck Harris Technically I agree that they have a lot in common. But I think the large devices, which are often not cylindrical, are usually called light pipes. http://uk.mouser.com/Mobile/Optoelectronics/LED-Indication/LED-Light-Pipes/_/N-b1d20 Some light pipes are hollow inside. I think that is stretching the definition of optical fibre. According to Wikipedia, light pipes or light tubes were originally developed by the ancient Egyptians. Some of these things are hollow are more than 1 m in diameter. I would hardly call that an optical fibre. But call them what you fancy (optical fibre, multi more fibre, waveguide, light tube, light pipe. ...) I think such a device might solve the problem getting the LTE Lite's status LEDs onto a box. I don't have an LTE Lite, but given that they are low power devices, where heat generation is undesirable, I suspect that the light output level might be a bit low. In which case a photodiode or similar may be needed. Dave. ___ 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] LTE-Lite
Mount the LTE-lite to the front panel with a cutout and a green bezel so you can see the LEDs directly. -- Brian Lloyd Lloyd Aviation 706 Flightline Drive Spring Branch, TX 78070 br...@lloyd.aero +1.210.802-8FLY (1.210.802-8359) ___ 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] LTE-Lite
The OP said he couldn't find anything applicable when he was looking for light pipe. So, I offered him a suggestion for why. Ultimately, we are talking about locating something using a search engine. The public has taken to the high tech sounding term fiber optic to describe what used to be called a light pipe. If it is thin, and flexible, and moves light from one location to another, it will be known to most people as fiber optic. As an example, sitting here on my workbench is a light that I use to illuminate objects under my Olympus stereo microscope. It is made by Nikon, and has the following words inscribed on its panel: NIKON, Inc. MKII Fiber Optic Light Do you imagine that it is a precision glass or plastic waveguide, or just a flexible light pipe? -Chuck Harris paul swed wrote: That is a good suggestion. But I fall into the camp. Not really that important now. At least not to get me to pull it out of the rack. :-) The little LED are pretty bright and I remember some broadcast equipment used light pipes. OK now I am going to get silly but this is time-nuts. I think light pipe and fiber optics are two different terms. Yes they both pass light. But a fiber optic is a precision glass or plastic waveguide. A light pipe is a bulk piece of plastic that is not a wave guide in respect to the accuracy of the walls. Oh I am so doomed now that I said that. Regards Paul WB8TSL ___ 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] LTE-Lite
actually, Magritte had it: “this is not a pipe” Don On Dec 5, 2014, at 8:01 AM, Chuck Harris cfhar...@erols.com wrote: The OP said he couldn't find anything applicable when he was looking for light pipe. So, I offered him a suggestion for why. Ultimately, we are talking about locating something using a search engine. The public has taken to the high tech sounding term fiber optic to describe what used to be called a light pipe. If it is thin, and flexible, and moves light from one location to another, it will be known to most people as fiber optic. As an example, sitting here on my workbench is a light that I use to illuminate objects under my Olympus stereo microscope. It is made by Nikon, and has the following words inscribed on its panel: NIKON, Inc. MKII Fiber Optic Light Do you imagine that it is a precision glass or plastic waveguide, or just a flexible light pipe? -Chuck Harris paul swed wrote: That is a good suggestion. But I fall into the camp. Not really that important now. At least not to get me to pull it out of the rack. :-) The little LED are pretty bright and I remember some broadcast equipment used light pipes. OK now I am going to get silly but this is time-nuts. I think light pipe and fiber optics are two different terms. Yes they both pass light. But a fiber optic is a precision glass or plastic waveguide. A light pipe is a bulk piece of plastic that is not a wave guide in respect to the accuracy of the walls. Oh I am so doomed now that I said that. Regards Paul WB8TSL ___ 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] LTE-Lite
I finally took an ineterest in this thread, because I have needed (rather infrequently) a way to get LED light from a PCB to a front panel. I Googled flexible light pipe (no quotes in the Google search) and got loads of hits for them. So, I guess they're called pipes after all. And they're stocked at Mouser, in various sizel and lengths. How quaint! Check out Mouser's catalog page at http://www.mouser.com/catalog/catalogusd/647/186.pdf. There's probably more, but this was as far as I went. Cheers, Dave M Don Latham wrote: actually, Magritte had it: “this is not a pipe” Don On Dec 5, 2014, at 8:01 AM, Chuck Harris cfhar...@erols.com wrote: The OP said he couldn't find anything applicable when he was looking for light pipe. So, I offered him a suggestion for why. Ultimately, we are talking about locating something using a search engine. The public has taken to the high tech sounding term fiber optic to describe what used to be called a light pipe. If it is thin, and flexible, and moves light from one location to another, it will be known to most people as fiber optic. As an example, sitting here on my workbench is a light that I use to illuminate objects under my Olympus stereo microscope. It is made by Nikon, and has the following words inscribed on its panel: NIKON, Inc. MKII Fiber Optic Light Do you imagine that it is a precision glass or plastic waveguide, or just a flexible light pipe? -Chuck Harris paul swed wrote: That is a good suggestion. But I fall into the camp. Not really that important now. At least not to get me to pull it out of the rack. :-) The little LED are pretty bright and I remember some broadcast equipment used light pipes. OK now I am going to get silly but this is time-nuts. I think light pipe and fiber optics are two different terms. Yes they both pass light. But a fiber optic is a precision glass or plastic waveguide. A light pipe is a bulk piece of plastic that is not a wave guide in respect to the accuracy of the walls. Oh I am so doomed now that I said that. Regards Paul WB8TSL ___ 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] LTE-Lite
On 5 Dec 2014 20:05, Dave M dgmin...@mediacombb.net wrote: I finally took an ineterest in this thread, because I have needed (rather infrequently) a way to get LED light from a PCB to a front panel. I Googled flexible light pipe (no quotes in the Google search) and got loads of hits for them. So, I guess they're called pipes after all. I can't help feeling that the name(s) of the device(s) that will allow one to get light from an LED on a PCB to a front panel is a bit off-topic. I think it is fair to say we have ascertained that different people call them by different names, and searching using Google with different names will likely bring benefits over searching with one name. IMHO, we should close this particular part of the thread. Dave ___ 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] LTE-Lite
With the LTE-Lite, are the survey results held in non-volatile memory, or does it need to do a survey each time it is switched on? This is a fixed location. The survey light is still on after a number of hours of operation (but it may have gone off in the meanwhile), and the GPS light sometimes flashes and sometimes not. The signals I'm seeing at the moment are: 24 30 26 18 32 27 21 18 and 19 in the signal quality indicator of Visual GPS. This with the puck on the top storey of a two storey building, but indoors. Other GPS pucks work fine in the same location. The PPS output appears to be correct, and there is 20 MHz from the 20 MHz port, but nothing from the Clock Out port on this 10 MHz unit. The unit is as-received, with the exception of switching to NMEA sentences. Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] LTE-Lite
David it always does a survey. Though even while doing that the frequency output is fine after its had a bit to stabilize. I wanted to bring the survey lamp out to a front panel LED however that appeared to be more work and risk then the value. The documentation says that from time to time it will do a re-survey. Frankly my units racked and stacked with dividers filters and line drivers for various frequencies I am using and its running very very smoothly. By the way at a huge power consumption of 1-3 watts. The power mete doesn't read well at this level. Regards Paul WB8TSL On Thu, Dec 4, 2014 at 11:07 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: With the LTE-Lite, are the survey results held in non-volatile memory, or does it need to do a survey each time it is switched on? This is a fixed location. The survey light is still on after a number of hours of operation (but it may have gone off in the meanwhile), and the GPS light sometimes flashes and sometimes not. The signals I'm seeing at the moment are: 24 30 26 18 32 27 21 18 and 19 in the signal quality indicator of Visual GPS. This with the puck on the top storey of a two storey building, but indoors. Other GPS pucks work fine in the same location. The PPS output appears to be correct, and there is 20 MHz from the 20 MHz port, but nothing from the Clock Out port on this 10 MHz unit. The unit is as-received, with the exception of switching to NMEA sentences. Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] LTE-Lite
David it always does a survey. Though even while doing that the frequency output is fine after its had a bit to stabilize. I wanted to bring the survey lamp out to a front panel LED however that appeared to be more work and risk then the value. The documentation says that from time to time it will do a re-survey. Frankly my units racked and stacked with dividers filters and line drivers for various frequencies I am using and its running very very smoothly. By the way at a huge power consumption of 1-3 watts. The power mete doesn't read well at this level. Regards Paul WB8TSL == Thanks, Paul. I had rather hoped that there might be some EEPROM in one of the chips where the data was stored, oh well! I wonder just how long a bit to stabilize takes? I might have mine on 24 x 7, but I might not... My survey LED has still not gone out despite the unit being on overnight, and the Alarm LED is lit, so I wish there was a way of relaxing the survey constraints a little to get the survey complete. Viewing the NMEA output with either Visual GPS or the U-blox software suggests that, despite good signals, the unit is only getting lock half the time. The positions it produces are correct. I read in the documentation that the serial/USB data is output only, though. (I was wrong on the 10 MHz output being 20 MHz, I forget my other reference was 5 MHz.) 73, David GM8ARV -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] LTE-Lite
SO, I just connected my third LTE-Lite unit. By the time the software drivers were installed, and I selected U-center to the new COMM port, it had a fix. Even with the survey LED still blinking. I looked at the GoogleEarth view, and the fix is within six feet of where the antenna really is. IMPRESSIVE. BTW, the 10 MHz unit I ran for a couple of days showed a fix on GoogleEarth within less than a foot of the antenna location. Most impressive. Jim On 11/28/2014 4:23 PM, Jim Sanford wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
I have for sale a 2 week old 10 Mhz LTE-Lite with power supply, right angle jumpers, and antenna as shipped from Said. An excellent unit - in about 15 minutes it will be within a few parts of 10e10. I am selling it as it would not work out for a project I was working on. $ 175.00 including shipping to lower 48. 73, Bill, WA2DVU Cape May, NJ --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
Hi Just so the rest of the world does not freak out when they look at accuracy compared to Google: Depending on just where you are, Google Maps / Google Earth can be more or less accurate. It’s not at all uncommon to find horizontal errors 20 feet. I have seen this with multiple locations that were surveyed to “couple centimeter accuracy. We’ve been into the details of why. You can dig into the archives for all the details. Bob On Nov 30, 2014, at 1:23 PM, Jim Sanford wb4...@wb4gcs.org wrote: SO, I just connected my third LTE-Lite unit. By the time the software drivers were installed, and I selected U-center to the new COMM port, it had a fix. Even with the survey LED still blinking. I looked at the GoogleEarth view, and the fix is within six feet of where the antenna really is. IMPRESSIVE. BTW, the 10 MHz unit I ran for a couple of days showed a fix on GoogleEarth within less than a foot of the antenna location. Most impressive. Jim On 11/28/2014 4:23 PM, Jim Sanford wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
Hi, Just a word of caution here: Do not trust Google Earth data for any precision work. The mentioned six feet are probably due to the geographical data, not to the precission of your GPS unit. If you look for image seams you can verify the kind of errors involved. Google Earth is not a professional data source, if you want to use it por precise work they offer the option to load your own maps and images for your use , but this is not a free service. The free service and data is good for showing your favorite pub to your friends. Regards. Ignacio EB4APL On 30/11/2014 a las 19:23, Jim Sanford wrote: SO, I just connected my third LTE-Lite unit. By the time the software drivers were installed, and I selected U-center to the new COMM port, it had a fix. Even with the survey LED still blinking. I looked at the GoogleEarth view, and the fix is within six feet of where the antenna really is. IMPRESSIVE. BTW, the 10 MHz unit I ran for a couple of days showed a fix on GoogleEarth within less than a foot of the antenna location. Most impressive. Jim On 11/28/2014 4:23 PM, Jim Sanford wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org ___ 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] LTE-Lite
eb4...@cembreros.jazztel.es said: Do not trust Google Earth data for any precision work. The mentioned six feet are probably due to the geographical data, not to the precission of your GPS unit. If you look for image seams you can verify the kind of errors involved. How good are USGS topo maps for this sort of thing? Most streets are shown as a pair of parallel lines, but the separation of the lines doesn't match the actual width of most streets. Does the center of that pair on the paper correspond to the center of the road? Can I use the intersection of a pair of streets as a reference point? ... How about equivalent maps for other countries? How well do typical benchmarks agree with GPS? Are the surveyors maps used for deeds useful in this context? -- These are my opinions. I hate spam. ___ 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] LTE-Lite
Hi You *know* what’s going to happen (it always does): You’ll get the LTE sold and the next day another project will pop up that it would be absolutely perfect for :) Bob On Nov 30, 2014, at 12:48 PM, billriches bill.ric...@verizon.net wrote: I have for sale a 2 week old 10 Mhz LTE-Lite with power supply, right angle jumpers, and antenna as shipped from Said. An excellent unit - in about 15 minutes it will be within a few parts of 10e10. I am selling it as it would not work out for a project I was working on. $ 175.00 including shipping to lower 48. 73, Bill, WA2DVU Cape May, NJ --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
Ignacio: Gracias. I only mentioned the GoogleEarth as an indicator . . . Setenta y Tres, Jim wb4...@amsat.org On 11/30/2014 4:11 PM, EB4APL wrote: Hi, Just a word of caution here: Do not trust Google Earth data for any precision work. The mentioned six feet are probably due to the geographical data, not to the precission of your GPS unit. If you look for image seams you can verify the kind of errors involved. Google Earth is not a professional data source, if you want to use it por precise work they offer the option to load your own maps and images for your use , but this is not a free service. The free service and data is good for showing your favorite pub to your friends. Regards. Ignacio EB4APL On 30/11/2014 a las 19:23, Jim Sanford wrote: SO, I just connected my third LTE-Lite unit. By the time the software drivers were installed, and I selected U-center to the new COMM port, it had a fix. Even with the survey LED still blinking. I looked at the GoogleEarth view, and the fix is within six feet of where the antenna really is. IMPRESSIVE. BTW, the 10 MHz unit I ran for a couple of days showed a fix on GoogleEarth within less than a foot of the antenna location. Most impressive. Jim On 11/28/2014 4:23 PM, Jim Sanford wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
On 30 November 2014 at 21:38, Bob Camp kb...@n1k.org wrote: Hi You *know* what’s going to happen (it always does): You’ll get the LTE sold and the next day another project will pop up that it would be absolutely perfect for :) Bob I don't know what the warranty situation would be on a used one. There was one for sale in the UK the other day, but it cost more than I could get one new for, although it could be shipped immediately, rather than in a few weeks. But I also worried a bit about the warranty. But I think I might get an HP OCXO based one instead. Dave ___ 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] LTE-Lite
On 11/30/14, 1:49 PM, Hal Murray wrote: eb4...@cembreros.jazztel.es said: Do not trust Google Earth data for any precision work. The mentioned six feet are probably due to the geographical data, not to the precission of your GPS unit. If you look for image seams you can verify the kind of errors involved. How good are USGS topo maps for this sort of thing? USGS National Map Accuracy Standards are 1/50th of an inch at map scale (essentially, the width of a pencil line). That is, things on the map are within 1/50th of an inch where they actually are. So, on a 1:250,000 map, one can expect 100 meter errors. On a 1:24,000 map, 10 meter errors, etc. Most streets are shown as a pair of parallel lines, but the separation of the lines doesn't match the actual width of most streets. That's the symbology: that is, you're seeing a map symbol for a street of a particular class, not the actual dimensions of the street. Does the center of that pair on the paper correspond to the center of the road? Can I use the intersection of a pair of streets as a reference point? ... No. What you could use is the center point for Bench Marks (BM) on the map, variously represented as crosses or triangles. And, of course, they're only accurate to 0.02 inches on the map (0.0508 cm). In practice, most USGS maps are somewhat better than this, assuming you allow for things like changes since the map revision date. My house is moving at roughly 1-2cm/year due to tectonic motion, and, so, a map that was revised in 1980 will be some 30-60cm in error. Since a 1:24,000 map is the standard 7.5 minute quad, there can be 12 meter uncertainty, and the map doesn't need to be updated. ANd then we get into map datums. Is your map NAD27 or WGS84? How about equivalent maps for other countries? How well do typical benchmarks agree with GPS? Are the surveyors maps used for deeds useful in this context? ___ 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] LTE-Lite
On 30/11/2014 a las 22:49, Hal Murray wrote: eb4...@cembreros.jazztel.es said: Do not trust Google Earth data for any precision work. The mentioned six feet are probably due to the geographical data, not to the precission of your GPS unit. If you look for image seams you can verify the kind of errors involved. How good are USGS topo maps for this sort of thing? Most streets are shown as a pair of parallel lines, but the separation of the lines doesn't match the actual width of most streets. Does the center of that pair on the paper correspond to the center of the road? Can I use the intersection of a pair of streets as a reference point? ... How about equivalent maps for other countries? How well do typical benchmarks agree with GPS? Are the surveyors maps used for deeds useful in this context? In fact I'm not familiar with USGS topo maps, but here in Spain for the small scales(Scale 1:25000 and lower) the streets and roads are not wide enough to be accurately represented, so a symbol is used instead. The symbol style is selected to mean the type of road and yes, the center of the parallel lines corresponds to the center of the street. Another thing is the overall precision, here it is established that the precision of the paper maps should be equal to the unaided eye resolution, about 1/4 mm, so you multiply .25 mm times the scale denominator and you get the precision. Our main national topographic map is at 1:25000 scale and its precision is about 6.25 meters. For digital maps the precision is what the map provider says, since a digital map can be enlarged at will. Usually the precision is consistent with the intended representation scale in the same terms as the paper maps. Since Google's geographical data is usually obtained from official sources, the line maps are quite good, but the satellite images usually are not very well rectified and stitched, unless they are obtained from similar sources which put a lot of effort on its accuracy and matching with the maps. This varies a lot depending the region. The surveyor maps usually agree very well with GPS, in fact they are based in GPS measured reference points these days. This comes from my limited experience, the results can be very different depending the zone and the date. Best regards, Ignacio EB4APL ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
Gents I have a S14WI GPS antenna splitter w. Opt : Amplified + DC Bias Select + Ant Current monitor It's connected to a Maxrad 40dB ice cone timing antenna DS for the spliter here http://www.amtechs.co.jp/2_gps/pdf/S14WI_spec.pdf http://tinyurl.com/nfmpyqm Currently i have this connected : Port1 : Tbolt Port2 : Z3810A Port3 : Reserved KS Lucent (Waiting for TNC-BNC adapter) Port4 : Reserved for LTE-Lite (hope to connect today) Port3/4 have a 50ohm (BNC ethernet terminator) on right now As i read the DS , the splitter currently used the antenna power from Port1, to power the antenna, and Port2 is terminated w. 200ohm. I'm a bit unsure about the DS , but as i read it it will isolate Port4 from the antenna DC , as it draws power from Port1 (Tbolt) The LTE-Lite is 3v3 , and wouldn't like to get 5v on it's antenna. If anyone could have a quick glance , and verify my assumptions i'd be gratefull. TIA CFO -Denmark -- E-mail:xne...@luna.dyndns.dk ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
xne...@luna.dyndns.dk said: The LTE-Lite is 3v3 , and wouldn't like to get 5v on it's antenna. I'd put a voltmeter on that connector and see if the splitter is sending anything out. My scan of the data sheet looks like it will do the right thing. -- These are my opinions. I hate spam. ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
Hi! The splitter will not route 5V back out to another splitter port. Your gpsd(tcx)o antenna port is safe. -- Björn div Originalmeddelande /divdivFrån: cfo xne...@luna.dyndns.dk /divdivDatum:2014-11-29 08:53 (GMT+01:00) /divdivTill: time-nuts@febo.com /divdivRubrik: [time-nuts] LTE-Lite and - S14WI 1x4 GPS splitter /divdiv /divGents I have a S14WI GPS antenna splitter w. Opt : Amplified + DC Bias Select + Ant Current monitor It's connected to a Maxrad 40dB ice cone timing antenna DS for the spliter here http://www.amtechs.co.jp/2_gps/pdf/S14WI_spec.pdf http://tinyurl.com/nfmpyqm Currently i have this connected : Port1 : Tbolt Port2 : Z3810A Port3 : Reserved KS Lucent (Waiting for TNC-BNC adapter) Port4 : Reserved for LTE-Lite (hope to connect today) Port3/4 have a 50ohm (BNC ethernet terminator) on right now As i read the DS , the splitter currently used the antenna power from Port1, to power the antenna, and Port2 is terminated w. 200ohm. I'm a bit unsure about the DS , but as i read it it will isolate Port4 from the antenna DC , as it draws power from Port1 (Tbolt) The LTE-Lite is 3v3 , and wouldn't like to get 5v on it's antenna. If anyone could have a quick glance , and verify my assumptions i'd be gratefull. TIA CFO -Denmark -- E-mail:xne...@luna.dyndns.dk ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
On Sat, 29 Nov 2014 10:54:17 +0100, Björn wrote: Hi! The splitter will not route 5V back out to another splitter port. Your gpsd(tcx)o antenna port is safe. Thanx Hal Björn I have connected it , and it seems to be running fine It has been on for about 1 hr now. $PJLTS,-4.14,-9.10,3870,6,1.7941415,59.8047,9.4E-10,0,8,0x0*55 $PJLTS,-4.30,-9.10,3871,6,1.7941431,59.8047,9.3E-10,0,7,0x0*5C $PJLTS,-4.46,-9.10,3872,6,1.7941451,59.8048,9.3E-10,0,9,0x0*59 Björn do you have the same splitter , i know Magnus does /CFO ___ 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] LTE Lite installation comments
Want to thank everyone for the various comments and insights of the LTE, filters, buffers etc. My unit is built up including dividers and distribution amps and simply need to drill a few holes in the front panel for on/off switch and a few status lamps some 16 BNC's. I want to thank both Bob and Charles for the comments on using 74HC or AS as line drivers with LPF filters. A pair of inverters per coax or 3 lines per 74HC14. Simple and effective for the 10' of coax on the bench distribution. I calculated Low Pass Filters for 10, 5, 1, and .1 Mhz. The older VLF radios use .1 Mhz as a reference. Certainly I can not speak to some of the detailed comments mentioned on Time-Nuts as to jitter etc. But I can say on a spectrum analyzer the outputs look very good. I used Saids inverters for the 1 PPS. I was considering RS 232 and RS 422 and may add those but less of a priority. It seems I always have coax around so this is a pretty nice way to get PPS to a project. So from discussions to real in a few days. Damn technology. I was beginning to believe the old basement Telco RB that drives my stuff was starting to fail. Darned if this project didn't prove it. I could see the RB jitter and occasionally loose lock. OK another project on the list. Regards Paul WB8TSL ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
Hi, I suggest that you use a DVM to see which ports are getting power. Better yet would be to disconnect everything and use an ohm-meter to see which ports are electrically connected. If you can't satisfy yourself that you know what's what, then contact GPS Source. They are very good people to deal with. I've got an MS-14 that had two powered ports plus the powered antenna port, plus it can be internally powered. I asked them about it, and they gave me instructions on how to de-power one of the ports. It was just a matter of removing a 000 shunt resistor and adding a 200 ohm load resistor. The way I read the product description is that the pick and choose likely means it has the same type of construction that mine does. A 000 resistor bypasses a blocking cap for power transfer ports, and you have to add a 200 ohm 1W (ex: CRCW2512200RJNEG) if you depower a port. But, contact them. They'll fix you right up. By the way, if your ports are labeled, PDC = powered DC and BDC = blocked DC. Bob - AE6RV From: cfo xne...@luna.dyndns.dk To: time-nuts@febo.com Sent: Saturday, November 29, 2014 1:53 AM Subject: [time-nuts] LTE-Lite and - S14WI 1x4 GPS splitter Gents I have a S14WI GPS antenna splitter w. Opt : Amplified + DC Bias Select + Ant Current monitor It's connected to a Maxrad 40dB ice cone timing antenna DS for the spliter here http://www.amtechs.co.jp/2_gps/pdf/S14WI_spec.pdf http://tinyurl.com/nfmpyqm Currently i have this connected : Port1 : Tbolt Port2 : Z3810A Port3 : Reserved KS Lucent (Waiting for TNC-BNC adapter) Port4 : Reserved for LTE-Lite (hope to connect today) Port3/4 have a 50ohm (BNC ethernet terminator) on right now As i read the DS , the splitter currently used the antenna power from Port1, to power the antenna, and Port2 is terminated w. 200ohm. I'm a bit unsure about the DS , but as i read it it will isolate Port4 from the antenna DC , as it draws power from Port1 (Tbolt) The LTE-Lite is 3v3 , and wouldn't like to get 5v on it's antenna. If anyone could have a quick glance , and verify my assumptions i'd be gratefull. TIA CFO -Denmark -- E-mail:xne...@luna.dyndns.dk ___ 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] LTE-Lite and - S14WI 1x4 GPS splitter
Checking on this and anything you get is a very good idea. - Someone could have opened it up and added/deleted parts, in this case +5V on one of the ports that is suppose to be just a 200 ohm load. - Could have been a factory special with knows what configuration. - and so on On Sat, Nov 29, 2014 at 10:13 AM, Bob Stewart b...@evoria.net wrote: Hi, I suggest that you use a DVM to see which ports are getting power. Better yet would be to disconnect everything and use an ohm-meter to see which ports are electrically connected. If you can't satisfy yourself that you know what's what, then contact GPS Source. They are very good people to deal with. I've got an MS-14 that had two powered ports plus the powered antenna port, plus it can be internally powered. I asked them about it, and they gave me instructions on how to de-power one of the ports. It was just a matter of removing a 000 shunt resistor and adding a 200 ohm load resistor. The way I read the product description is that the pick and choose likely means it has the same type of construction that mine does. A 000 resistor bypasses a blocking cap for power transfer ports, and you have to add a 200 ohm 1W (ex: CRCW2512200RJNEG) if you depower a port. But, contact them. They'll fix you right up. By the way, if your ports are labeled, PDC = powered DC and BDC = blocked DC. Bob - AE6RV From: cfo xne...@luna.dyndns.dk To: time-nuts@febo.com Sent: Saturday, November 29, 2014 1:53 AM Subject: [time-nuts] LTE-Lite and - S14WI 1x4 GPS splitter Gents I have a S14WI GPS antenna splitter w. Opt : Amplified + DC Bias Select + Ant Current monitor It's connected to a Maxrad 40dB ice cone timing antenna DS for the spliter here http://www.amtechs.co.jp/2_gps/pdf/S14WI_spec.pdf http://tinyurl.com/nfmpyqm Currently i have this connected : Port1 : Tbolt Port2 : Z3810A Port3 : Reserved KS Lucent (Waiting for TNC-BNC adapter) Port4 : Reserved for LTE-Lite (hope to connect today) Port3/4 have a 50ohm (BNC ethernet terminator) on right now As i read the DS , the splitter currently used the antenna power from Port1, to power the antenna, and Port2 is terminated w. 200ohm. I'm a bit unsure about the DS , but as i read it it will isolate Port4 from the antenna DC , as it draws power from Port1 (Tbolt) The LTE-Lite is 3v3 , and wouldn't like to get 5v on it's antenna. If anyone could have a quick glance , and verify my assumptions i'd be gratefull. TIA CFO -Denmark -- E-mail:xne...@luna.dyndns.dk ___ 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] LTE Lite installation comments
Hi You can check part of the performance of the buffers with your ‘scope. Trigger on the input and look at the output. Depending on what sort of scope you have, you might get sub ns. Of course you also could simply trust that logic gates have pretty stable delay specs. Bob On Nov 29, 2014, at 11:12 AM, paul swed paulsw...@gmail.com wrote: Want to thank everyone for the various comments and insights of the LTE, filters, buffers etc. My unit is built up including dividers and distribution amps and simply need to drill a few holes in the front panel for on/off switch and a few status lamps some 16 BNC's. I want to thank both Bob and Charles for the comments on using 74HC or AS as line drivers with LPF filters. A pair of inverters per coax or 3 lines per 74HC14. Simple and effective for the 10' of coax on the bench distribution. I calculated Low Pass Filters for 10, 5, 1, and .1 Mhz. The older VLF radios use .1 Mhz as a reference. Certainly I can not speak to some of the detailed comments mentioned on Time-Nuts as to jitter etc. But I can say on a spectrum analyzer the outputs look very good. I used Saids inverters for the 1 PPS. I was considering RS 232 and RS 422 and may add those but less of a priority. It seems I always have coax around so this is a pretty nice way to get PPS to a project. So from discussions to real in a few days. Damn technology. I was beginning to believe the old basement Telco RB that drives my stuff was starting to fail. Darned if this project didn't prove it. I could see the RB jitter and occasionally loose lock. OK another project on the list. Regards Paul WB8TSL ___ 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] LTE Lite installation comments
Hi If you are looking at the 10 MHz outputs and want to see what they are doing - feed a pair of outputs into a double balanced mixer. You will get an IF output that tracks the phase between the two outputs. Best to do it with 90 degrees of coax shifting things so you get a zero output. Track the voltage (maybe after a preamp) and you are measuring phase. Calibrate the mixer by changing the coax and you have pretty accurate information. Bob On Nov 29, 2014, at 11:12 AM, paul swed paulsw...@gmail.com wrote: Want to thank everyone for the various comments and insights of the LTE, filters, buffers etc. My unit is built up including dividers and distribution amps and simply need to drill a few holes in the front panel for on/off switch and a few status lamps some 16 BNC's. I want to thank both Bob and Charles for the comments on using 74HC or AS as line drivers with LPF filters. A pair of inverters per coax or 3 lines per 74HC14. Simple and effective for the 10' of coax on the bench distribution. I calculated Low Pass Filters for 10, 5, 1, and .1 Mhz. The older VLF radios use .1 Mhz as a reference. Certainly I can not speak to some of the detailed comments mentioned on Time-Nuts as to jitter etc. But I can say on a spectrum analyzer the outputs look very good. I used Saids inverters for the 1 PPS. I was considering RS 232 and RS 422 and may add those but less of a priority. It seems I always have coax around so this is a pretty nice way to get PPS to a project. So from discussions to real in a few days. Damn technology. I was beginning to believe the old basement Telco RB that drives my stuff was starting to fail. Darned if this project didn't prove it. I could see the RB jitter and occasionally loose lock. OK another project on the list. Regards Paul WB8TSL ___ 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] LTE-Lite
All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
Hi The “new chip ID, new com port” thing is pretty typical for the FTDI drivers. If you plug the old LTE back in there’s a good chance it will come back up as COMM 5. Usually they are pretty good about only adding ports for devices they have not seen before. Bob On Nov 28, 2014, at 3:23 PM, Jim Sanford wb4...@wb4gcs.org wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
All: Sharing lessons learned the hard way . . . After messing around with my Anti-Virus program, which declared some false threats, messing with drivers, and uninstalling/reinstalling Ublox, I put the 20 MHz unit back on line. Instantly came up and showed data in UBLOX. Shut it down, removed it, and reinstalled the 10 MHz unit which Winders7 called COMM6. Still nothing. Then looked at the LTE-Lite closely -- NMEA was not selected. Selected NMEA. Nothing. Selected COMM6. Nothing. Shifted to 38k4 baud -- instantly had data and a FIX!!! Even though survey LED is still blinking. Fix is pretty close to what I had from the unit that ran a week, PDOP is 1.5 and HDOP is 0.9. Pretty impressive. So, I must conclude that the problem was failure to check the board and make sure NMEA was selected. Hoping to save somebody my pain. 73, Jim wb4...@amsat.org On 11/28/2014 4:23 PM, Jim Sanford wrote: All: After running my 20 MHz LTE-Lite for a week or so, I shut it down and connected one of the 10 MHz units. The LEDs appear to be responding (survey still in progress) as per the quick start guide. Windows installed a new comm port and driver. (COMM6, with FTDI driver) The COMM5 port which was the 20 MHz unit is gone. U-center has selected COMM6 and is autobaud at 38000, but is showing my nothing except blank screens and a red NO FIX. Have I missed something? Or will it not report anything until a lock is achieved?? Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite
kb...@n1k.org said:
The ânew chip ID, new com portâ thing is pretty typical for the FTDI
drivers. If you plug the old LTE back in thereâs a good chance it will come
back up as COMM 5. Usually they are pretty good about only adding ports for
devices they have not seen before.
Most/some of the FTDI usb to serial chips have a serial number. I don't know
how it works on Windows, but on Linux, you can use the udev rules to make an
alias so your software can refer to something with a filename like /dev/LITE
rather than /dev/ttyUSB2. It works no matter which slot you plug it into
and/or still works after it gets unplugged and reconnected.
lsusb -v will show things like:
idVendor 0x0403 Future Technology Devices International, Ltd
idProduct 0x6001 FT232 USB-Serial (UART) IC
bcdDevice6.00
iManufacturer 1 FTDI
iProduct2 FT232R USB UART
iSerial 3 A102GX1N
/var/log/messages or /var/log/syslog will contain something like:
Nov 28 15:12:00 deb kernel: [1392082.791230] usb 3-3: Product: FT232R USB UART
Nov 28 15:12:00 deb kernel: [1392082.791235] usb 3-3: Manufacturer: FTDI
Nov 28 15:12:00 deb kernel: [1392082.791240] usb 3-3: SerialNumber: A102GX1N
Nov 28 15:12:00 deb kernel: [1392082.799337] ftdi_sio 3-3:1.0: FTDI USB
Serial Device converter detected
Nov 28 15:12:00 deb kernel: [1392082.799447] usb 3-3: Detected FT232RL
...
Nov 28 15:12:00 deb kernel: [1392082.805436] usb 3-3: FTDI USB Serial Device
converter now attached to ttyUSB3
This is what I put in /etc/udev/rules.d/35-hgm.rules
# LTE LITE Eval Board
KERNEL==ttyUSB*, ATTRS{serial}==A102GX1N, MODE=0666, SYMLINK+=LITE
I use the same approach with my Rigol scope and Prologic USB-GPIB.
--
These are my opinions. I hate spam.
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Re: [time-nuts] LTE-Lite
On Fri, Nov 28, 2014 at 3:42 PM, Hal Murray hmur...@megapathdsl.net wrote: kb...@n1k.org said: The “new chip ID, new com port” thing is pretty typical for the FTDI drivers. If you plug the old LTE back in there’s a good chance it will come back up as COMM 5. Usually they are pretty good about only adding ports for devices they have not seen before. Most/some of the FTDI usb to serial chips have a serial number. I don't know how it works on Windows, but on Linux, you can use the udev rules to make an alias so your software can refer to something with a filename like /dev/LITE rather than /dev/ttyUSB2. It works no matter which slot you plug it into and/or still works after it gets unplugged and reconnected. It's really a limitation of USB. You have the vendor ID, product ID, and for some devices, a serial number. IF the device has a serial number, next time it's plugged in, the OS can be pretty certain it's the same device and can use the same COM port or device assignment as last time. If not, all bets are off. If a USB device has no serial number, Windows choses to use the physical USB port the device is plugged into. I.e. if you plug such a device with the same vendor ID/product ID into the same USB port, you get the same COM port assignment. I really don't know of a better way. It's unfortunate that for a device with no serial number, if you plug the same device into a different USB port, you get a different COM port, but it is the best solution for the case where you have more than one USB device with the same vendor ID/product ID... it works just the same as traditional RS232 ports: the COM port assignment depends on which socket you plug the device in. It is also unfortunate that the USB specs allowed this to happen and didn't require devices to have a serial number. ___ 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] LTE-Lite
For Linux, I worked this up and posted to linuxquestions.org. I don't
guarantee it, but it's been working for the PL-2303 devices for me. It just
creates a link to the real driver. There are probably better ways to do it.
File: /etc/udev/rules.d/70-persistent-usb.rulesACTION==add,
KERNEL==ttyUSB[0-9]*, PROGRAM=/etc/udev/rules.d/usb-parse-devpath.pm %p,
SYMLINK+=ttyUSB%c
File: /etc/udev/rules.d/usb-parse-devpath.pm#!/usr/bin/perl -w
@items = split(/, $ARGV[0]);
for ($i = 0; $i @items; $i++) {
if ($items[$i] =~ m/^usb[0-9]+$/) {
if ($items[$i + 2] =~ m/:/) {
print $items[$i + 1] . \n;
} else {
print $items[$i + 2] . \n;
}
last;
}
}
Example:
crw-rw 1 root dialout 188, 0 Nov 28 20:59 /dev/ttyUSB0
crw-rw 1 root dialout 188, 1 Nov 28 23:43 /dev/ttyUSB1
lrwxrwxrwx 1 root root 7 Nov 17 23:39 /dev/ttyUSB1-2 - ttyUSB0
lrwxrwxrwx 1 root root 7 Nov 22 21:17 /dev/ttyUSB4-2 - ttyUSB1
If the two code boxes don't make it through the list forwarder, the code can be
found here. Read the whole thread as I didn't put it all in the final post:
www.linuxquestions.org/questions/linux-hardware-18/usb-pl2303-reliable-device-names-4175506134/
Bob
From: Orin Eman orin.e...@gmail.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Friday, November 28, 2014 11:41 PM
Subject: Re: [time-nuts] LTE-Lite
On Fri, Nov 28, 2014 at 3:42 PM, Hal Murray hmur...@megapathdsl.net wrote:
kb...@n1k.org said:
The “new chip ID, new com port” thing is pretty typical for the FTDI
drivers. If you plug the old LTE back in there’s a good chance it will
come
back up as COMM 5. Usually they are pretty good about only adding ports
for
devices they have not seen before.
Most/some of the FTDI usb to serial chips have a serial number. I don't
know
how it works on Windows, but on Linux, you can use the udev rules to make
an
alias so your software can refer to something with a filename like
/dev/LITE
rather than /dev/ttyUSB2. It works no matter which slot you plug it into
and/or still works after it gets unplugged and reconnected.
It's really a limitation of USB. You have the vendor ID, product ID, and
for some devices, a serial number.
IF the device has a serial number, next time it's plugged in, the OS can be
pretty certain it's the same device and can use the same COM port or device
assignment as last time. If not, all bets are off.
If a USB device has no serial number, Windows choses to use the physical
USB port the device is plugged into. I.e. if you plug such a device with
the same vendor ID/product ID into the same USB port, you get the same COM
port assignment. I really don't know of a better way. It's unfortunate
that for a device with no serial number, if you plug the same device into a
different USB port, you get a different COM port, but it is the best
solution for the case where you have more than one USB device with the same
vendor ID/product ID... it works just the same as traditional RS232 ports:
the COM port assignment depends on which socket you plug the device in.
It is also unfortunate that the USB specs allowed this to happen and didn't
require devices to have a serial number.
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Re: [time-nuts] LTE Lite SkyTraq chip info
As I say a most useless website. Regards On Tue, Nov 25, 2014 at 10:35 PM, Dave Martindale dave.martind...@gmail.com wrote: I spent a bit of time poking around the SkyTraq web site on the weekend. I couldn't find a datasheet for the chip on the LTE-Lite - perhaps it's so new that SkyTraq has not put together the datasheet yet. Under timing, they only list the Venus638LPx-T, which is a older (2011 copyright on the datasheet) 65-channel receiver. The LTE-Lite documentation mentions 65 channels somewhere too, suggesting that the LTE-Lite started out using this chip. Under navigation receivers, Skytraq lists the newer (2013) Venus838FLPx with 167 channels. So I would assume that the Venus838LPx-T-L used in the LTE-Lite is the same 167-channel hardware with timing firmware, and that the LTE-Lite switched from the 638LPx-T to the 838LPx-T-L sometime during development. - Dave On Tue, Nov 25, 2014 at 5:12 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. I personally use the uBlox software because the Skytrack software had a habit of crashing itself and my computer from time to time.. In a message dated 11/25/2014 14:02:41 Pacific Standard Time, paulsw...@gmail.com writes: Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-bo ard/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE-Lite Plans
Said, Your drawing looks better than those by Bob Pease, and he was never embarrassed by his :) Thank you for your extensive contributions to time nuts Didier KO4BB On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said ___ 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] LTE-Lite Plans
:) Sent From iPhone On Nov 26, 2014, at 9:20, Didier Juges shali...@gmail.com wrote: Said, Your drawing looks better than those by Bob Pease, and he was never embarrassed by his :) Thank you for your extensive contributions to time nuts Didier KO4BB On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said ___ 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] LTE-Lite Plans
Interesting comment. . . . I'm reading Bob's book now! Never met him, but felt like I knew him from all of his writings. His death was very sad Jim wb4...@amsat.org On 11/26/2014 12:20 PM, Didier Juges wrote: Said, Your drawing looks better than those byBob Pease, and he was never embarrassed by his :) Thank you for your extensive contributions to time nuts Didier KO4BB On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite Plans
Jim, A double tragedy. I was working with Jim Williams on one of our designs a week before he passed away. Then Bob crashed his car coming from Jim's funeral (grief?) and died too. Two of the greatest analog minds lost within days. Bye, Said Sent From iPhone On Nov 26, 2014, at 9:34, Jim Sanford wb4...@wb4gcs.org wrote: Interesting comment. . . . I'm reading Bob's book now! Never met him, but felt like I knew him from all of his writings. His death was very sad Jim wb4...@amsat.org On 11/26/2014 12:20 PM, Didier Juges wrote: Said, Your drawing looks better than those byBob Pease, and he was never embarrassed by his :) Thank you for your extensive contributions to time nuts Didier KO4BB On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE Lite SkyTraq chip info
Hi! Navspark has one board with Glonass (http://navspark.mybigcommerce.com/navspark-gl-arduino-compatible-development-board-with-gps-glonass/) and one board with Beidou (http://navspark.mybigcommerce.com/navspark-bd-arduino-compatible-development-board-with-gps-beidou/). Both use a Venus 8 engine. There is also a timming version (http://www.navspark.com.tw/blog/more-ns-t-programmable-frequency-testing) with a programmable frequency output. It has a LEON3 Sparc-V8 core and can be programmed with Arduino IDE. Edésio On Tue, Nov 25, 2014 at 10:29:19PM +, Poul-Henning Kamp wrote: In message 7da89.51b7dfcf.41a65...@aol.com, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] LTE Lite SkyTraq chip info
Poul are you teferring to the lte lite specifically? My Resolution SMT GG will go single sat or OD mode with only non GPS sats available. On Tuesday, November 25, 2014, Poul-Henning Kamp p...@phk.freebsd.dk wrote: In message 7da89.51b7dfcf.41a65...@aol.com javascript:;, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com javascript:; 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] LTE-Lite Plans
Didier: Please DO share. Thanks! Jim On 11/25/2014 7:47 PM, Didier Juges wrote: Jim, I have somewhere a piece of VB 6.0 code that decodes NMEA sentences and puts it pretty on the screen (at least that's how I remember it :). I am not at home at the moment but I'll be glad to send it to you if you are interested. May not do what you want, but it will get you started. Didier KO4BB www.ko4bb.com On November 25, 2014 1:42:42 PM CST, Jim Miller j...@jtmiller.com wrote: I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite Plans
On 25 November 2014 at 19:51, S. Jackson via time-nuts time-nuts@febo.com wrote: Jim, please remember you need proper lightning protection if you put the antenna outside.. bye, Said ___ 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] LTE Lite SkyTraq chip info
Sorry, seems this did not show first time. Edésio On Tue, Nov 25, 2014 at 09:16:20PM -0200, Edesio Costa e Silva wrote: Hi! Navspark has one board with Glonass (http://navspark.mybigcommerce.com/navspark-gl-arduino-compatible-development-board-with-gps-glonass/) and one board with Beidou (http://navspark.mybigcommerce.com/navspark-bd-arduino-compatible-development-board-with-gps-beidou/). Both use a Venus 8 engine. There is also a timming version (http://www.navspark.com.tw/blog/more-ns-t-programmable-frequency-testing) with a programmable frequency output. It has a LEON3 Sparc-V8 core and can be programmed with Arduino IDE. Edésio On Tue, Nov 25, 2014 at 10:29:19PM +, Poul-Henning Kamp wrote: In message 7da89.51b7dfcf.41a65...@aol.com, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] LTE-Lite Plans
yes please! Don On Nov 26, 2014, at 11:45 AM, Jim Sanford wb4...@wb4gcs.org wrote: Didier: Please DO share. Thanks! Jim On 11/25/2014 7:47 PM, Didier Juges wrote: Jim, I have somewhere a piece of VB 6.0 code that decodes NMEA sentences and puts it pretty on the screen (at least that's how I remember it :). I am not at home at the moment but I'll be glad to send it to you if you are interested. May not do what you want, but it will get you started. Didier KO4BB www.ko4bb.com On November 25, 2014 1:42:42 PM CST, Jim Miller j...@jtmiller.com wrote: I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite Plans
I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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] LTE-Lite Plans
Jim, please remember you need proper lightning protection if you put the antenna outside.. bye, Said In a message dated 11/25/2014 11:43:09 Pacific Standard Time, jim@jtmil ler.com writes: I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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] LTE-Lite Plans
Jim Because of the short runs you should be quite fine with your approach. I used the 74HC version to do my dividing using the second section to get 5 MHz. Lots of gear still uses that. Frankly ublox and such don't show you much and I am using PUTTY. There is another pgm from India but shows much the same as ublox. They do show more if NEMA. But what we want typically is the status. So the suggestion of VB is very reasonable to create a more useful interface. That is mostly watching the frequency offset and such in the status message. I sure all that can be dressed up easily and nicely. Regards Paul WB8TSL On Tue, Nov 25, 2014 at 2:42 PM, Jim Miller j...@jtmiller.com wrote: I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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] LTE-Lite Plans
On 25 November 2014 at 19:42, Jim Miller j...@jtmiller.com wrote: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. You could consider using a light pipe, fibre optic or whatever you want to call it. Perspex or similar material will guide light from an LED by total internal reflection. You could probably use a panel-mounted LED, remove the electronics and just use the lens, and holder so it looks better than it would be able do with just a hole. Dave ___ 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] LTE Lite SkyTraq chip info
Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-board/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE Lite SkyTraq chip info
Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. I personally use the uBlox software because the Skytrack software had a habit of crashing itself and my computer from time to time.. In a message dated 11/25/2014 14:02:41 Pacific Standard Time, paulsw...@gmail.com writes: Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-bo ard/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE Lite SkyTraq chip info
Said Really did not run it very long a few hours. In that time it ran fine and on Vista no less. Now thats scary. The fact that it had my location and insists on Asia along with fixed screen scaling hints that its half beaked. But there was little additional value compared to ublox accept for one thing I noticed. On ublox the update to the C/N updates every other second same with other screens. Then blanks the screen and repeats. A bit annoying. PUTTY isn't pretty but has what I care about. The offset. Regards Paul WB8TSL On Tue, Nov 25, 2014 at 5:12 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. I personally use the uBlox software because the Skytrack software had a habit of crashing itself and my computer from time to time.. In a message dated 11/25/2014 14:02:41 Pacific Standard Time, paulsw...@gmail.com writes: Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-bo ard/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE Lite SkyTraq chip info
In message 7da89.51b7dfcf.41a65...@aol.com, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] LTE Lite SkyTraq chip info
Thanks for the link. The Navspark also uses a Venus GPS, but I don't know if it the same one. I can't look it up at the moment. Joe Gray W5JG On Nov 25, 2014 3:02 PM, paul swed paulsw...@gmail.com wrote: Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-board/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE Lite SkyTraq chip info
Hi I think it’s more a supply and demand thing right now. There are a lot of systems (CDMA for example) that run on GPS time. There do not seem to be quite as many people putting out spec’s for the other systems (yet). Bob On Nov 25, 2014, at 5:29 PM, Poul-Henning Kamp p...@phk.freebsd.dk wrote: In message 7da89.51b7dfcf.41a65...@aol.com, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] LTE Lite SkyTraq chip info
We evaluated a Glonass unit for 1PPS and it was really quite bad. Unless you are near the poles or get jammed a lot I would not see much advantage.. Sent From iPhone On Nov 25, 2014, at 15:10, Bob Camp kb...@n1k.org wrote: Hi I think it’s more a supply and demand thing right now. There are a lot of systems (CDMA for example) that run on GPS time. There do not seem to be quite as many people putting out spec’s for the other systems (yet). Bob On Nov 25, 2014, at 5:29 PM, Poul-Henning Kamp p...@phk.freebsd.dk wrote: In message 7da89.51b7dfcf.41a65...@aol.com, S. Jackson via time-nuts writes : Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. That reminds me: I have yet to see anthing that uses Galileo or GNONASS in a position-hold mode, are those constellations still not competitive with GPS in that niche ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] LTE-Lite Plans
Jim, I have somewhere a piece of VB 6.0 code that decodes NMEA sentences and puts it pretty on the screen (at least that's how I remember it :). I am not at home at the moment but I'll be glad to send it to you if you are interested. May not do what you want, but it will get you started. Didier KO4BB www.ko4bb.com On November 25, 2014 1:42:42 PM CST, Jim Miller j...@jtmiller.com wrote: I have one of the LTE-Lite 20Mhz units and plan to use it as a frequency reference for my ham radio gear. My planned setup is as follows: I'm putting it in the recommended Hammond enclosure powered by a USB cable from my PC. I had originally planned to use the wall wart provided but I want to get status from the unit without hacking a window in the top to see the LEDs so I plan to use TBD software to provide a status check. I briefly thought about doing something with an Arduino and display shields but that seemed like too much work for now. I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to provide 10Mhz. The chip and associated passives will be on a little circuit board mounted in the open area normally reserved for the external oscillator. The output of the chip will be connected via a series resistor of about 400 ohms to a SMA connector. This resistor will limit the load on the FF and the LTE-Lite power source. Power will be taken from C6. This output will only go a few inches to a DEMI 10Mhz 4 way splitter The input of the splitter will be equipped with an additional ERA-2+ amplifier (50 ohm input) which will restore the signal levels lost due to the series resistor in the LTE-Lite addon. The DEMI splitter will also be equipped with a manual power switch which will allow me to kill the output of the box if the GPSDO fails for some reason. The little hockey puck antenna will be mounted directly outside the shack wall near a south facing wall which will limit the visibility to only half the horizon. I'm assuming this will be enough for my modest needs. The four outputs will be used as follows: One will go to the K3 ExtREF to provide an external reference. Two will go to separate TX/RX converters for low frequency (600Khz) use and be used with the transverter I/O on the K3. The last will be used as a general calibration reference. When the power switch on the DEMI splitter is turned off the K3 will revert to using its internal TXCO. I leave the PC running 24/7 and the power to the LTE-Lite would only be interrupted when the PC is rebooted. I don't need a frequency reference during the reboot time since I always operate my rig with the PC on and running. The TBD status software will tell me when the LTE-Lite is synched up again. The PC is served by a UPS and the shack circuit is one which is served by our whole house generator. I have the DEMI splitter built up and working. Now just waiting on enclosure from Digikey. I should have everything running by mid December. I still need to figure out what to use for the status software. Ideally I'd like an applet to display appropriate status indications on my monitor for now I'll examine the uBlox and Putty and if not satisfactory perhaps I'll write something in VB. Feedback and suggestions welcome. 73 Jim ab3cv ___ 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. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things. ___ 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] LTE-Lite Plans
Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said ___ 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] LTE-Lite Plans
Hi If you decide to run the circuit from +5V, get the 74ACT04 instead of the 74AC04. It will trigger better on the 3.3V output from the LTE. The 74AC(T)04 will not in any way impact the phase noise or ADEV coming out of the LTE, if a reasonable supply is used… With a decent PCB layout and SMT parts, the isolation can be *very* good if multiple gate packages are used. Bob On Nov 25, 2014, at 8:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said CMOS_buffer_for_LTE-Lite-Eval.JPG___ 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] LTE-Lite Plans
Hi Mark, Bob, two comments: * I forgot to mention that feeding the 1PPS signal through the IC inverts the signal of course, so the falling edge becomes the active edge. Use the two inverters in series rather than parallel to avoid that problem, at the cost of lower drive capability and higher Tpd. * On the interaction between the three signals: the worst is when the 1PPS signal hits and drives 3V into the 100 Ohms equivalent termination (30mA). At that point the power supply will sag, causing AM modulation to appear on the RF signals. The result is humps in the ADEV plot at 1Hz, 2Hz, 3Hz, etc etc all the way up to a couple of KHz. This is why separate power supplies and driver IC's are recommended (a separate LDO for the RF signals and one just for the 1PPS would solve this 1PPS crosstalk). This is one reason why I don't like DC 50 Ohms terminations and love open-ended coax cables. In fact Tom V.B. some years ago reported here that he could measure the 1PPS LED current (!!!) from one of his GPSDOs as it fed THROUGH THE AC POWER LINE into another unit.. Albeit at levels of xE-014 or lower if I remember correctly.. bye, Said In a message dated 11/25/2014 17:51:37 Pacific Standard Time, m...@alignedsolutions.com writes: Thanks Said. Strangely enough I was just about to ask the group for comments re the practicality of using inverters in parallel with resistors as a simple means of buffering 1 pps signals. I'll give this a try. Thanks Mark Spencer On 2014-11-25, at 5:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said CMOS_buffer_for_LTE-Lite-Eval.JPG ___ 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] LTE-Lite Plans
Hi One simple point: Do you *need* ultra low phase noise on your 1 pps output or is real good ADEV all you are after? If you need good phase noise .. exactly what are you doing ??? So… tack a 78L05 onto your bulk power and run the pps output “empire” off of that supply. Maybe wire the 1 pps stuff on it’s own little chunk of PCB material. Save the fancy low noise regulator(s) for the 10 MHz “empire”. ( If you get a good one, 78L05 might do just fine there as well). What’s the massive cost impact of this radical approach? Well the inverter chips are $0.20 each from several outfits. The 78L05 is also $0.20. The resistors and caps should be on your bench already. If not plan on another $0.30 for the bunch. So you have added (at most) $0.70 to the cost of the circuit by doing this. Skip the order of fries with lunch and it’s paid for. The above does not include the cost of connectors, enclosure, power or switches. All of that will be part of any design you do. Enclosures and power are going to be lower with this circuit than just about anything else you could do. No hogging pockets out of a 1 foot cube of aluminum required ….. Bob On Nov 25, 2014, at 9:14 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Hi Mark, Bob, two comments: * I forgot to mention that feeding the 1PPS signal through the IC inverts the signal of course, so the falling edge becomes the active edge. Use the two inverters in series rather than parallel to avoid that problem, at the cost of lower drive capability and higher Tpd. * On the interaction between the three signals: the worst is when the 1PPS signal hits and drives 3V into the 100 Ohms equivalent termination (30mA). At that point the power supply will sag, causing AM modulation to appear on the RF signals. The result is humps in the ADEV plot at 1Hz, 2Hz, 3Hz, etc etc all the way up to a couple of KHz. This is why separate power supplies and driver IC's are recommended (a separate LDO for the RF signals and one just for the 1PPS would solve this 1PPS crosstalk). This is one reason why I don't like DC 50 Ohms terminations and love open-ended coax cables. In fact Tom V.B. some years ago reported here that he could measure the 1PPS LED current (!!!) from one of his GPSDOs as it fed THROUGH THE AC POWER LINE into another unit.. Albeit at levels of xE-014 or lower if I remember correctly.. bye, Said In a message dated 11/25/2014 17:51:37 Pacific Standard Time, m...@alignedsolutions.com writes: Thanks Said. Strangely enough I was just about to ask the group for comments re the practicality of using inverters in parallel with resistors as a simple means of buffering 1 pps signals. I'll give this a try. Thanks Mark Spencer On 2014-11-25, at 5:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said CMOS_buffer_for_LTE-Lite-Eval.JPG ___ 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
Re: [time-nuts] LTE-Lite Plans
Bob, Its not the 1PPS that would be suffering, its the 10MHz that will have all the 1Hz and its harmonics making the PN graph look ugly.. Agree with you that the regulators cost zip these days and using individual buffer ICs and regs is the best way to go. Bye, Said Sent From iPhone On Nov 25, 2014, at 18:45, Bob Camp kb...@n1k.org wrote: Hi One simple point: Do you *need* ultra low phase noise on your 1 pps output or is real good ADEV all you are after? If you need good phase noise .. exactly what are you doing ??? So… tack a 78L05 onto your bulk power and run the pps output “empire” off of that supply. Maybe wire the 1 pps stuff on it’s own little chunk of PCB material. Save the fancy low noise regulator(s) for the 10 MHz “empire”. ( If you get a good one, 78L05 might do just fine there as well). What’s the massive cost impact of this radical approach? Well the inverter chips are $0.20 each from several outfits. The 78L05 is also $0.20. The resistors and caps should be on your bench already. If not plan on another $0.30 for the bunch. So you have added (at most) $0.70 to the cost of the circuit by doing this. Skip the order of fries with lunch and it’s paid for. The above does not include the cost of connectors, enclosure, power or switches. All of that will be part of any design you do. Enclosures and power are going to be lower with this circuit than just about anything else you could do. No hogging pockets out of a 1 foot cube of aluminum required ….. Bob On Nov 25, 2014, at 9:14 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Hi Mark, Bob, two comments: * I forgot to mention that feeding the 1PPS signal through the IC inverts the signal of course, so the falling edge becomes the active edge. Use the two inverters in series rather than parallel to avoid that problem, at the cost of lower drive capability and higher Tpd. * On the interaction between the three signals: the worst is when the 1PPS signal hits and drives 3V into the 100 Ohms equivalent termination (30mA). At that point the power supply will sag, causing AM modulation to appear on the RF signals. The result is humps in the ADEV plot at 1Hz, 2Hz, 3Hz, etc etc all the way up to a couple of KHz. This is why separate power supplies and driver IC's are recommended (a separate LDO for the RF signals and one just for the 1PPS would solve this 1PPS crosstalk). This is one reason why I don't like DC 50 Ohms terminations and love open-ended coax cables. In fact Tom V.B. some years ago reported here that he could measure the 1PPS LED current (!!!) from one of his GPSDOs as it fed THROUGH THE AC POWER LINE into another unit.. Albeit at levels of xE-014 or lower if I remember correctly.. bye, Said In a message dated 11/25/2014 17:51:37 Pacific Standard Time, m...@alignedsolutions.com writes: Thanks Said. Strangely enough I was just about to ask the group for comments re the practicality of using inverters in parallel with resistors as a simple means of buffering 1 pps signals. I'll give this a try. Thanks Mark Spencer On 2014-11-25, at 5:28 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Guys, I never expected such an intense discussion about using and buffering the outputs from the LTE-Lite board since the actual circuit to use can be quite simple. To address these questions, I drew up a simple schematic that uses a DIP-14 74AC04 gate, six resistors, and two caps. Everyone who can solder should be able to build this simple circuit as a dead-bug type build on a copper-clad board. This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on pin 14 of that part on the eval board, even though I would strongly suggest to use a separate low noise 3.3V or 5V power supply to power the 74AC04 chip. You can add 100nF caps in series to the two RF signals before they feed into the coax output connectors for less power consumption and removing DC for instruments that don't like DC inputs. Using a single IC for the three signals will result in crosstalk between the signals, but it should be clear from the schematics how one could break up the signals by using three independent ICs to minimize crosstalk. We use this circuit in a small box here using SMT components, and it works really well. Excuse my horrible writing, using keyboards has made my fingers numb.. Hope that helps, Said CMOS_buffer_for_LTE-Lite-Eval.JPG ___ 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
Re: [time-nuts] LTE Lite SkyTraq chip info
I spent a bit of time poking around the SkyTraq web site on the weekend. I couldn't find a datasheet for the chip on the LTE-Lite - perhaps it's so new that SkyTraq has not put together the datasheet yet. Under timing, they only list the Venus638LPx-T, which is a older (2011 copyright on the datasheet) 65-channel receiver. The LTE-Lite documentation mentions 65 channels somewhere too, suggesting that the LTE-Lite started out using this chip. Under navigation receivers, Skytraq lists the newer (2013) Venus838FLPx with 167 channels. So I would assume that the Venus838LPx-T-L used in the LTE-Lite is the same 167-channel hardware with timing firmware, and that the LTE-Lite switched from the 638LPx-T to the 838LPx-T-L sometime during development. - Dave On Tue, Nov 25, 2014 at 5:12 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Now that the cat is out of the bag - notice that on these boards we used the special -T timing version which is more than twice as expensive than the normal navigation version used by others.. I personally use the uBlox software because the Skytrack software had a habit of crashing itself and my computer from time to time.. In a message dated 11/25/2014 14:02:41 Pacific Standard Time, paulsw...@gmail.com writes: Here is a link to a company that at least shares details of the SkyTraq venus 8 chip on the LTE-Lite. The actual skytraq sites is pretty useless. https://www.tindie.com/products/smokingresistor/venus838flpx-gps-breakout-bo ard/ There is a program that will read the nema codes and such also. Have used it and its not better or worse then ublox. A bit of humor it only ever shows Asia for the ground track. The venus 8 seems to have a lot of capability. Not sure how to get to it, but the fact is for the LTE Lite its not needed. It has a single job to perform. It would be curious to obtain the board tindie sells because it supports all of the satellites. But have to say thats a project for another day wa down the list. But at least you can have some further technical details for the system. Regards Paul WB8TSL ___ 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] LTE-lite pigtails
My unit didn't come with right-angle pigtails as shown in the doc (and Tom's photos). Did anyone else get straight connectors? ___ 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] LTE-lite pigtails
My first unit came with straight connectors. I can manage. On 11/23/2014 1:50 PM, Paul wrote: My unit didn't come with right-angle pigtails as shown in the doc (and Tom's photos). Did anyone else get straight connectors? ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-lite pigtails
Paul Mine came with right angles. It does make for a nicer arrangement. Regards Paul WB8TSL On Sun, Nov 23, 2014 at 2:26 PM, Jim Sanford wb4...@wb4gcs.org wrote: My first unit came with straight connectors. I can manage. On 11/23/2014 1:50 PM, Paul wrote: My unit didn't come with right-angle pigtails as shown in the doc (and Tom's photos). Did anyone else get straight connectors? ___ 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE lite questions
Nigel, CC'ing time nuts.. R2 and R3 are stuffing options, see the schematics in the user manual. Typically you don't have to solder anything. The default is set for the low-noise 3.0V to be fed to the DIP-14 tcxo for best performance. On your question on removing the SMT Tcxo, this is not easy, but possible with a heat gun. Its easy to melt the adjacent switches though when doing that. The RTV over it should just peel off, but we have not tried that yet. There is no way to just remove power to the internal Tcxo unfortunately. This is why I had suggested the 19.2MHz version for people who want to use the external oscillator option, because that won't beat with your oscillator close-in. I was a bit surprised that so few of those 19.2MHz units sold compared to the significant numbers for 10/20MHz units. In either case I think the resulting beat spurs are typically lower than many other GPSDOs and oscillators have in their spurs, the CSAC with its spurs comes to mind.. Hope that helps, Said Sent from my iPad On Nov 22, 2014, at 6:08, gandal...@aol.com wrote: Hi Said, Sorry to bother you again, I'm not sure is this is an oversight or deliberate but I've just noticed that R2 has not been fitted to my evaluation board. I'm a bit concerned as this will affect power to the external oscillator and R2 would be difficult to fit now that SW2 is installed. I may have missed this if it was mentioned on the Time-Nuts list but there's a lot there to look through so thought it best to ask you direct. Regards Nigel GM8PZR Sent from my iPad ___ 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] LTE-Lite Antenna
All: Received my LTE-Lite and ready to play, EXCEPT, I'm in the basement. Does anyone know if the antenna which the ebay purveyor of the Nortel Thunderbolts supplies will work on the 3.3 volts coming out of the LTE Lite? (I measured the Nortel, it puts 4.95 volts on the coax.) That antenna has the advantage of being at altitude with a feedline run to the basement. Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite Antenna
Hi Pretty much all of the “timing” GPS antennas want to see 5V to work properly. About the only thing I’ve seen that likes 3.3V are the modern mag mount antennas. Bob On Nov 22, 2014, at 4:55 PM, Jim Sanford wb4...@wb4gcs.org wrote: All: Received my LTE-Lite and ready to play, EXCEPT, I'm in the basement. Does anyone know if the antenna which the ebay purveyor of the Nortel Thunderbolts supplies will work on the 3.3 volts coming out of the LTE Lite? (I measured the Nortel, it puts 4.95 volts on the coax.) That antenna has the advantage of being at altitude with a feedline run to the basement. Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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] LTE-Lite Antenna
Jim, try it out. Check the C/No values in the GPGSV NMEA messages. If they are over 40dB, then it works just fine and there is no need to over-think the issue.. bye, Said In a message dated 11/22/2014 16:39:55 Pacific Standard Time, kb...@n1k.org writes: Hi Pretty much all of the “timing” GPS antennas want to see 5V to work properly. About the only thing I’ve seen that likes 3.3V are the modern mag mount antennas. Bob On Nov 22, 2014, at 4:55 PM, Jim Sanford wb4...@wb4gcs.org wrote: All: Received my LTE-Lite and ready to play, EXCEPT, I'm in the basement. Does anyone know if the antenna which the ebay purveyor of the Nortel Thunderbolts supplies will work on the 3.3 volts coming out of the LTE Lite? (I measured the Nortel, it puts 4.95 volts on the coax.) That antenna has the advantage of being at altitude with a feedline run to the basement. Thanks, Jim wb4...@amsat.org --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ___ 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-nu ts 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] LTE-Lite Antenna
Hi Jim, not much harm should come to the 5V antenna if driven at only 3.3V. However if you feed 5V into the LTE Lite antenna port then bad things will happen because it will back-feed into the 3.3V power rail, and possible damage some of the 3.3V parts on the PCB. Running a 3.3V antenna port with external 5V feeding in is never a good idea.. That said you can actually power the unit from 3.3V coming from another unit through just the antenna port. Don't ask me how I know.. bye, Said In a message dated 11/22/2014 18:09:16 Pacific Standard Time, wb4...@wb4gcs.org writes: SAID: After checking schematics, was contemplating exactly this. I wanted to make sure I can't do any harm, and it appears not. Will probably give it a try tomorrow If it doesn't work, I've come up with a bias-T and amplifier. Will have to spin a PCB, tho. Will advise. Jim On 11/22/2014 8:46 PM, _SAIDJACK@aol.com_ (mailto:saidj...@aol.com) wrote: Jim, try it out. Check the C/No values in the GPGSV NMEA messages. If they are over 40dB, then it works just fine and there is no need to over-think the issue.. bye, Said In a message dated 11/22/2014 16:39:55 Pacific Standard Time, _kb8tq@n1k.org_ (mailto:kb...@n1k.org) writes: Hi Pretty much all of the “timing” GPS antennas want to see 5V to work properly. About the only thing I’ve seen that likes 3.3V are the modern mag mount antennas. Bob On Nov 22, 2014, at 4:55 PM, Jim Sanford _wb4...@wb4gcs.org_ (mailto:wb4...@wb4gcs.org) wrote: All: Received my LTE-Lite and ready to play, EXCEPT, I'm in the basement. Does anyone know if the antenna which the ebay purveyor of the Nortel Thunderbolts supplies will work on the 3.3 volts coming out of the LTE Lite? (I measured the Nortel, it puts 4.95 volts on the coax.) That antenna has the advantage of being at altitude with a feedline run to the basement. Thanks, Jim _wb4gcs@amsat.org_ (mailto:wb4...@amsat.org) --- This email has been checked for viruses by Avast antivirus software. _http://www.avast.com_ (http://www.avast.com/) ___ time-nuts mailing list -- _time-nuts@febo.com_ (mailto: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_ (mailto:time-nuts@febo.com) To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. (http://www.avast.com/) This email has been checked for viruses by Avast antivirus software. _www.avast.com_ (http://www.avast.com/) ___ 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] LTE-Lite Antenna
Hi On Nov 22, 2014, at 9:14 PM, S. Jackson via time-nuts time-nuts@febo.com wrote: Hi Jim, not much harm should come to the 5V antenna if driven at only 3.3V. However if you feed 5V into the LTE Lite antenna port then bad things will happen because it will back-feed into the 3.3V power rail, and possible damage some of the 3.3V parts on the PCB. Running a 3.3V antenna port with external 5V feeding in is never a good idea.. That said you can actually power the unit from 3.3V coming from another unit through just the antenna port. Don't ask me how I know.. I wonder how well that works with an OCXO based unit….. Bob bye, Said In a message dated 11/22/2014 18:09:16 Pacific Standard Time, wb4...@wb4gcs.org writes: SAID: After checking schematics, was contemplating exactly this. I wanted to make sure I can't do any harm, and it appears not. Will probably give it a try tomorrow If it doesn't work, I've come up with a bias-T and amplifier. Will have to spin a PCB, tho. Will advise. Jim On 11/22/2014 8:46 PM, _SAIDJACK@aol.com_ (mailto:saidj...@aol.com) wrote: Jim, try it out. Check the C/No values in the GPGSV NMEA messages. If they are over 40dB, then it works just fine and there is no need to over-think the issue.. bye, Said In a message dated 11/22/2014 16:39:55 Pacific Standard Time, _kb8tq@n1k.org_ (mailto:kb...@n1k.org) writes: Hi Pretty much all of the “timing” GPS antennas want to see 5V to work properly. About the only thing I’ve seen that likes 3.3V are the modern mag mount antennas. Bob On Nov 22, 2014, at 4:55 PM, Jim Sanford _wb4...@wb4gcs.org_ (mailto:wb4...@wb4gcs.org) wrote: All: Received my LTE-Lite and ready to play, EXCEPT, I'm in the basement. Does anyone know if the antenna which the ebay purveyor of the Nortel Thunderbolts supplies will work on the 3.3 volts coming out of the LTE Lite? (I measured the Nortel, it puts 4.95 volts on the coax.) That antenna has the advantage of being at altitude with a feedline run to the basement. Thanks, Jim _wb4gcs@amsat.org_ (mailto:wb4...@amsat.org) --- This email has been checked for viruses by Avast antivirus software. _http://www.avast.com_ (http://www.avast.com/) ___ time-nuts mailing list -- _time-nuts@febo.com_ (mailto: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_ (mailto:time-nuts@febo.com) To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. (http://www.avast.com/) This email has been checked for viruses by Avast antivirus software. _www.avast.com_ (http://www.avast.com/) ___ 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] LTE-Lite order
Hello everyone, some info to the hole list for folks who missed out on the 20MHz LTE-Lite Evaluation kits: The 20MHz units shipped-out last week to all of you who ordered and should arrive shortly. Also, we have received feedback from the 10MHz TCXO factory that TCXOs will ship to us sooner than first quoted, so we just reduced the lead-time for the 10MHz DIP-14 TCXO units on eBay to four weeks from today. We also were able to increase the number available if anyone else is interested. Thanks again everyone, Said ___ 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] LTE Lite Came!!
Hi Jim, thanks for your question. The reason we put that note in there is two-fold: 1) On these 20MHz units the TCXO output in fact can drive 50 Ohms inputs as we put a strong buffer on the board, but the synthesized RF output and the 1PPS output cannot drive 50 Ohms. Those two are CMOS 1M Ohms input only. Using 50 Ohms impedance on the TCXO output will however heavily tax the internal power supply and CMOS buffer, and create heating on the board right next to the TCXO which will affect stability somewhat. So can it be done? Yes. Should it be done? That's up to the user to decide. 2) On the next batch of 10MHz DIP-14 TCXO units the external TCXO itself drives the output directly without a buffer. That TCXO is not capable of driving 50 Ohms inputs, only CMOS 1M Ohms inputs. So a buffer is required on these 10MHz units if 50 Ohms test equipment is to be used. Hope that explains it, bye, Said In a message dated 11/17/2014 15:27:21 Pacific Standard Time, j...@jtmiller.com writes: Hello Said I got a nice surprise in my mail today: LTE-Lite! There was a note with it that said (in effect) none of the outputs are 50ohm capable. So it looks like I should build up a little board with the divide by two and incorporate on that a 50ohm capable buffer for clock transmission to the rest of my system? BTW, you're welcome to answer via Timenuts as I'm sure others will have the same question. Thanks! Jim AB3CV ___ 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] LTE Lite Question
I got my LTE Lite this afternoon and have been playing with it. I have a question on the NMEA $PSTI message: what are the last two numbers before the checksum (in this case 30, 0)? I've noticed that once the site survey is complete they go away, just the comma is left. $PSTI,00,1,1701,4.4,30,0*35 ___ 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] LTE LITE comments
Said Like others my unit arrived today. As I pondered the cables from the splitter and power supplies along with lots of mcx connectors, low and behold everything needed was in the box to get going. Its up and running, surveyed, locked, and happy. Currently watching it against a z3801 and a KS-36421. Looks pretty good. Compared to the power consumption those others use amazing. Thanks Paul WB8TSL ___ 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] LTE LITE comments
Thanks Paul, Glad you like it! On the PSTI question from earlier: the GPS vendor snuck two additional fields into the PSTI message on their last fw update. The two new fields are as follows: Position Standard Deviation Threshold Calculated Position Standard Deviation After Self-Survey The first is simply 30, and the second should indicate the final fix quality. The second has to be smaller than the first for the survey process to end. Both in meters. Bye, Said Sent From iPhone On Nov 17, 2014, at 18:17, paul swed paulsw...@gmail.com wrote: Said Like others my unit arrived today. As I pondered the cables from the splitter and power supplies along with lots of mcx connectors, low and behold everything needed was in the box to get going. Its up and running, surveyed, locked, and happy. Currently watching it against a z3801 and a KS-36421. Looks pretty good. Compared to the power consumption those others use amazing. Thanks Paul WB8TSL ___ 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] LTE-Lite module
Bob wrote: PHK has a roughly 6 line code snippet that does a basic PLL. Add two more lines to check / clamp the integrator if you wish. That's 8 lines. If you want a D term (to give it an FLL component) add 2 more lines. We're up to 10 lines. It's just a control loop, not a full GPSDO. There's not a lot to it. There's a bit more to it than that. For any loop slow (narrowband) enough to be useful disciplining a good OCXO, I consider a dual- or triple-rate loop filter to be essential. There is also always a fair amount of error-trapping, and other overhead. These can add lines fairly quickly. I'm sure I have lots more to learn about writing efficient code. (But note that there is a difference between coding one's chosen algorithm more efficiently and choosing a different algorithm that is not really what you want, just because it is more efficient.) Best regards, Charles ___ 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] LTE-Lite module
Hi We are not talking about a system (like GPS) that has junk data coming in. In this case, the phase detector gives you a very good estimate of the delta between input and output in real time. The error trapping / shifting / multi this and that simply isn’t needed in this case. The solution is much easier than the GPSDO. Let the OCXO warm up for a day or two. Yes it could be a week. Adjust it with a pot to be close to frequency. (This is a basement project). Fire up the loop. Let it settle. Come back in an hour or two and all is well. Confirm this by watching a (good) DVM on the EFC line. It’s a low gain / long time constant loop. It will take a bit to settle. Yes, if code is what gets you excited, put in an array for the coefficients. Then add a timer to step the index. The timer will add about 4 lines. The step process will be on auto-pilot, but that makes it easy. You will settle faster, the net result after settling will be about the same. If a year from now it’s unlocked, re-adjust the pot. Maybe check it with a DVM every so often and adjust it before it unlocks. Not a lot to it. Simple code to write Easy board to build. Does just what it needs to do. Not a commercial system at all. It does not need to be. It’s going to do everything you need to do and be much easier to get running than something far more complex. The idea is to make the simplest system that will do the trick, not make it so hard that nobody ever tries. The target audience is a basement experimenter not NIST. It’s ok in this case to replace a bunch of code with an inquiring mind. Bob On Oct 25, 2014, at 11:23 AM, Charles Steinmetz csteinm...@yandex.com wrote: Bob wrote: PHK has a roughly 6 line code snippet that does a basic PLL. Add two more lines to check / clamp the integrator if you wish. That's 8 lines. If you want a D term (to give it an FLL component) add 2 more lines. We're up to 10 lines. It's just a control loop, not a full GPSDO. There's not a lot to it. There's a bit more to it than that. For any loop slow (narrowband) enough to be useful disciplining a good OCXO, I consider a dual- or triple-rate loop filter to be essential. There is also always a fair amount of error-trapping, and other overhead. These can add lines fairly quickly. I'm sure I have lots more to learn about writing efficient code. (But note that there is a difference between coding one's chosen algorithm more efficiently and choosing a different algorithm that is not really what you want, just because it is more efficient.) Best regards, Charles ___ 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] LTE-Lite module
Mostly we don't even write the guts of those algorithms. For example, you'd use a PID library. One line to create a PID controller object then one line to call the PID for each phase measurement. This goes double for, say, drawing a graph of the phase over time to an LCD display, you'd use a graphic library for that. And for communicating over USB to a computer. Who would want to take time to learn the details of USB and LCD graphic controllers? Most code we write is just glue that connects functions. After a a few decades doing this I'd have to say that reinventing well-tested wheels is the certain mark of a beginner/amateur. Either they don't understand how to use these libraries or they don't know they exist or think they can do it better. They spend 4X longer to get something working and then it still does not cover all the corner cases and exceptions those libraries might cover. Ages ago CPU performance or space might mean you HAD to tightly code, but now even a $1.79 8-bit AVR chip can hold well over the equivalent of 1,000 lines of C++ code. OK there is the case a manufactures who wants to be able to use the $1.69 chip and save 10 cents but most projects are not going to be built in high qualities. Back on-tpic. Now that we have many low cast ($10 and under) uP development boards building a GPSDO is simple. You don't even need a custom PCB or many chips. And the simple $10 controller can have a fancy LCD screen and connect to a computer and log stats and it can all be up and running in a day or two. If someone today wanted a harder challenge type project that would push the state of that art out a little, why not build an ensemble type device? One that accepts PPS timing from several sources, figures out in realtime which of them to accept then runs several local oscillators, perhaps an Rb and a couple OCXOs and compares their outputs. So now you use both Rb and GPS, maybe a few of each to track timing. A while back I tried to prove to myself how easy it is now to build a GPSDO that was good enough to drive typical lab equipment. Something like a dozen lines of C code and $8 did it. It's no longer cutting edge to built these. Time to think about the next generation kind of low-cost device. So maybe one could combine the best properties of several different kinds of devices? Has this been done yet? On Sat, Oct 25, 2014 at 8:23 AM, Charles Steinmetz csteinm...@yandex.com wrote: Bob wrote: PHK has a roughly 6 line code snippet that does a basic PLL. Add two more lines to check / clamp the integrator if you wish. That's 8 lines. If you want a D term (to give it an FLL component) add 2 more lines. We're up to 10 lines. It's just a control loop, not a full GPSDO. There's not a lot to it. There's a bit more to it than that. For any loop slow (narrowband) enough to be useful disciplining a good OCXO, I consider a dual- or triple-rate loop filter to be essential. There is also always a fair amount of error-trapping, and other overhead. These can add lines fairly quickly. I'm sure I have lots more to learn about writing efficient code. (But note that there is a difference between coding one's chosen algorithm more efficiently and choosing a different algorithm that is not really what you want, just because it is more efficient.) Best regards, Charles ___ 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. -- Chris Albertson Redondo Beach, California ___ 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] LTE-Lite module and the pendulum...
I'm not sure if you're referring to my comment about the Vectron VCXO jumping when I tried to adjust it or some other part of the discussion. I was definitely referring to adjusting the screw on the side of the Vectron VCXO that I believe is a piston capacitor. I suppose it could be a 10-turn trimpot. From: saidj...@aol.com To: time-nuts@febo.com Subject: Re: [time-nuts] LTE-Lite module and the pendulum... Hi John, while I can't tell you which vendors are affected and which are not (Its like asking an angler for his secret angling spot :), I can say that most low cost TCXOs exhibit this behavior, and are thus not really suitable for GPSDOs. The ones we used on the LTE-Lite are quite good and do not exhibit this behavior. They are also 10x more expensive than the lost cost TCXOs in the exact same package that are typically used in non-critical applications. So far none of the quite reputable TCXO and OCXO vendors that I contacted about the problem can explain the behavior to me, like I said they were not even aware of the issue and had no way to test for it, and I had to prove it to them by sending our units to them so they can see the issue for themselves. Bye, Said In a message dated 10/21/2014 11:51:28 Pacific Daylight Time, j...@miles.io writes: Great insight thanks. You nailed it: out with the old oscillator and in with one that doesn't have that problem. Btw the mechanical tuning issue you mentioned is essentially the same exact problem: even the slightest turn will make the frequency jump too high or too low. It can drive you (and the loop) crazy trying to get it on-frequency. Whenever I've seen this behavior, it has always been caused by uncertainty or quantization on the part of the trimpot's wiper, rather than anything that could be blamed on the varactor. What would be a good example of a TCXO or OCXO model that exhibits EFC hysteresis? I don't immediately understand what could cause this phenomenon, and I'd like to reproduce it here to see what's happening. -- john, KE5FX Miles Design LLC Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] LTE-Lite module
In message 766d6811-f733-4ab2-8574-24e4606e4...@aol.com, Said Jackson via tim e-nuts writes: Thats exactly right Bob. By the time your ocxo jumps to catch up to the efc voltage, you have oversteered, then the process starts in reverse and the ocxo jumps in the opposite direction. This is a well known PI effect called windup. The cause is a phase offset of opposite sign of the frequency offset. The fix is simple: Start running with only the P term, and engage the I term only after 1. The input phase offset changes sign or 2a. The input phase offset levels off or 2b. Some calibrated amount of time has passed. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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.
