Re: [time-nuts] Inexpensive modular gps with 1pps
David, Hal, Thank you very much for the pointers, and the hand-holding. I ordered a unit from Sure last month, which arrived last week. I used David's excellent instructions, and I am happy to report that the unit (cabled to a 1U Linux server, Debian testing) is working well (or so I think). ntpq -pn : remote refid st t when poll reach delay offset jitter == +127.127.28.0.GPS.0 l 13 16 3770.000 -19.214 12.250 *127.127.28.1.PPS.0 l 12 16 3770.0000.001 0.001 -203.123.48.6223.255.185.22 u6 64 3770.1079.251 0.016 -203.123.48.218 223.255.185.22 u 23 64 3770.160 -6.036 0.045 -118.143.17.82 .MRS.1 u 29 64 377 88.536 24.006 0.745 #54.251.61.122 158.108.212.149 3 u 18 64 3777.372 -0.099 1.773 x203.129.68.14 192.168.51.203 2 u 43 64 365 210.371 84.157 0.289 x123.108.109.9 118.143.17.822 u 26 64 377 116.259 39.154 0.509 #202.131.74.126 210.0.235.14 3 u 26 64 377 42.854 -1.611 0.610 -192.53.103.104 .PTB.1 u 53 64 377 353.5501.066 24.731 -131.188.3.222 .PPS.1 u6 64 377 361.439 -7.954 0.625 +133.100.11.8.GPS.1 u 10 64 377 105.521 -7.343 1.407 -121.182.147.191 .GPS.1 u 55 64 377 128.1773.004 12.558 -2001:df0:232:ee .NICT. 1 u 14 64 377 91.4020.443 2.651 This server (and others syncing with it) are members of the sg.pool.ntp.org, and hence hopefully helping others. The gpsd output is visible here: http://bit.ly/VwfkAt To the Time-Nuts in general, thanks a ton. To David in particular, your instructions are very, very, clear. My colleague, who soldered the two wires for me, now wants a clock to display the time in the server room. I shall show him photos of Nixie clocks :-) -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane On Sat, Dec 15, 2012 at 3:15 PM, David J Taylor david-tay...@blueyonder.co.uk wrote: Thank you, nice summary. One of my problems is that I am in Singapore. Soldering is not an issue in itself, but I cannot just order transistors and other small components online. You mention low cost units which require you to add a power connector, etc. Could you recommend any that can be bought online? With RS-232, please? Sanjeev Gupta ==**=== Sanjeev, It sounds as if this unit may suit: http://www.satsignal.eu/ntp/**Sure-GPS.htmhttp://www.satsignal.eu/ntp/Sure-GPS.htm It has RS-232 (true levels, not CMOS) and requires only two wires to be soldered. Order from: http://www.sureelectronics.**net/goods.php?id=99http://www.sureelectronics.net/goods.php?id=99 Cheers, 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-nutshttps://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] Inexpensive modular gps with 1pps
gha...@gmail.com said: You mention low cost units which require you to add a power connector, etc. Could you recommend any that can be bought online? With RS-232, please? There are two obvious choices. A bit of googling may find more details and/or other boards. -- The new favorite is the Sure demo board. http://www.sureelectronics.net/goods.php?id=99 http://www.sureelectronics.net/goods.php?id=98 (The version with the Bluetooth is cheaper than the one without. ??) http://www.satsignal.eu/ntp/Sure-GPS.htm -- The old standby is the Garmin GPS-18x-LVC. Garmin makes several versions of the GPS-18x. http://www8.garmin.com/manuals/GPS18x_TechnicalSpecifications.pdf Be sure to get the LVC version. The others don't have a PPS. I got mine from Provantage for roughly $70. http://www.provantage.com/garmin-010-00321-36~AGRMO006.htm Setup info: http://time.qnan.org/ http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm The GPS-18 (no x) is the older version. You probably can't find it for sale. It's much less sensitive, but gave much better timing over the serial port. -- The GlobalSat MR350P is another option. It comes with a PS2 connector, but you can chop that off. Their adapter cable doesn't include the PPS. http://www.usglobalsat.com/p-58-mr-350p-bulkhead.aspx http://www.usglobalsat.com/store/download/58/mr350p_ds_ug.pdf That PPS is only 1 uSec wide which may be too narrow for some/most systems to capture. They sell a couple of adapter cables, but none of them support PPS. You can stretch the PPS signal with the TAPR FatPPS. http://www.tapr.org/kits_fatpps.html -- 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] Inexpensive modular gps with 1pps
On 12/15/2012 12:19 AM, Hal Murray wrote: gha...@gmail.com said: You mention low cost units which require you to add a power connector, etc. Could you recommend any that can be bought online? With RS-232, please? There are two obvious choices. A bit of googling may find more details and/or other boards. -- The new favorite is the Sure demo board. http://www.sureelectronics.net/goods.php?id=99 http://www.sureelectronics.net/goods.php?id=98 (The version with the Bluetooth is cheaper than the one without. ??) http://www.satsignal.eu/ntp/Sure-GPS.htm -- The old standby is the Garmin GPS-18x-LVC. Garmin makes several versions of the GPS-18x. http://www8.garmin.com/manuals/GPS18x_TechnicalSpecifications.pdf Be sure to get the LVC version. The others don't have a PPS. I got mine from Provantage for roughly $70. http://www.provantage.com/garmin-010-00321-36~AGRMO006.htm Setup info: http://time.qnan.org/ http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm The GPS-18 (no x) is the older version. You probably can't find it for sale. It's much less sensitive, but gave much better timing over the serial port. -- The GlobalSat MR350P is another option. It comes with a PS2 connector, but you can chop that off. Their adapter cable doesn't include the PPS. http://www.usglobalsat.com/p-58-mr-350p-bulkhead.aspx http://www.usglobalsat.com/store/download/58/mr350p_ds_ug.pdf That PPS is only 1 uSec wide which may be too narrow for some/most systems to capture. They sell a couple of adapter cables, but none of them support PPS. You can stretch the PPS signal with the TAPR FatPPS. http://www.tapr.org/kits_fatpps.html Does this provide 10 MHz or 1pps? -- Chuck Forsberg WA7KGX N2469R c...@omen.com www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc The High Reliability Software 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 ___ 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] Inexpensive modular gps with 1pps
c...@omen.com said: Does this provide 10 MHz or 1pps? None of the low-cost units that I know about provide 10 MHz. Most of them provide crappy timing via NMEA over a serial port. The ones I mentioned include PPS. -- 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] Inexpensive modular gps with 1pps
On Fri, Nov 16, 2012 at 9:10 AM, Hal Murray hmur...@megapathdsl.net wrote: jim...@earthlink.net said: Big enough that Synergy Garmin have pricing for anywhere from 1 to 1000 units I don't know of any GPS units with PPS that are both low cost and no soldering. There are several low cost units that come in a nice small package. But you can't just plug them into your PC. You have to provide power and add a connector. There are quite a few more units if you don't need a nice package. There are several no-soldering packages. I haven't seen one that is low cost. There are many low cost GPS devices that use USB without any soldering. They don't have PPS. Thank you, nice summary. One of my problems is that I am in Singapore. Soldering is not an issue in itself, but I cannot just order transistors and other small components online. You mention low cost units which require you to add a power connector, etc. Could you recommend any that can be bought online? With RS-232, please? -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ___ 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] Inexpensive modular gps with 1pps
Thank you, nice summary. One of my problems is that I am in Singapore. Soldering is not an issue in itself, but I cannot just order transistors and other small components online. You mention low cost units which require you to add a power connector, etc. Could you recommend any that can be bought online? With RS-232, please? Sanjeev Gupta = Sanjeev, It sounds as if this unit may suit: http://www.satsignal.eu/ntp/Sure-GPS.htm It has RS-232 (true levels, not CMOS) and requires only two wires to be soldered. Order from: http://www.sureelectronics.net/goods.php?id=99 Cheers, 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] Inexpensive modular gps with 1pps
How can being in Singapore be a problem for acquiring components online? Element14/Farnell have their Asian warehouse there, they even have free overnight delivery by courier to Malaysia where I currently live. ( Or just go offline and get down to Sim Lim tower and get your parts there ^_^_ ) -mats On Sat, Dec 15, 2012 at 2:41 PM, Sanjeev Gupta gha...@gmail.com wrote: One of my problems is that I am in Singapore. Soldering is not an issue in itself, but I cannot just order transistors and other small components online. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ___ 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] Inexpensive modular gps with 1pps
i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, 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] Inexpensive modular gps with 1pps
On 11/15/12 4:30 AM, David J Taylor wrote: i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, David ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. ___ 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] Inexpensive modular gps with 1pps
On Thu, 15 Nov 2012 05:02:54 -0800, Jim Lux jim...@earthlink.net wrote: On 11/15/12 4:30 AM, David J Taylor wrote: i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, David ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. I picked up a used Garmin GPS18-5Hz hockey puck to play with and after updating the firmware, have gotten good results with the cable going out a window and the unit sitting on the lower edge of the roof. Its 5 pulse per second output has 60ns of resolution according to the Racal Dana 1992 I repaired implying about a 16.6 MHz timing clock. ___ 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] Inexpensive modular gps with 1pps
On 11/15/12 5:33 AM, David wrote: On Thu, 15 Nov 2012 05:02:54 -0800, Jim Lux jim...@earthlink.net wrote: On 11/15/12 4:30 AM, David J Taylor wrote: i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, David ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. I picked up a used Garmin GPS18-5Hz hockey puck to play with and after updating the firmware, have gotten good results with the cable going out a window and the unit sitting on the lower edge of the roof. Its 5 pulse per second output has 60ns of resolution according to the Racal Dana 1992 I repaired implying about a 16.6 MHz timing clock. That's the kind of thing I'm looking for.. or the Synergy TrakPuck ... or one of those pods that came with mapping software 5-10 years ago. I wonder if there's a new version of the GPS18, since I need something that is available off the shelf (and likely to remain so for at least 2-3 years).. Is there a timing output on the GPS16x? (or are the serial messages synchronized in some way) ___ 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] Inexpensive modular gps with 1pps
On Thu, 15 Nov 2012 06:07:28 -0800, Jim Lux jim...@earthlink.net wrote: On 11/15/12 5:33 AM, David wrote: On Thu, 15 Nov 2012 05:02:54 -0800, Jim Lux jim...@earthlink.net wrote: On 11/15/12 4:30 AM, David J Taylor wrote: i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, David ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. I picked up a used Garmin GPS18-5Hz hockey puck to play with and after updating the firmware, have gotten good results with the cable going out a window and the unit sitting on the lower edge of the roof. Its 5 pulse per second output has 60ns of resolution according to the Racal Dana 1992 I repaired implying about a 16.6 MHz timing clock. That's the kind of thing I'm looking for.. or the Synergy TrakPuck ... or one of those pods that came with mapping software 5-10 years ago. I wonder if there's a new version of the GPS18, since I need something that is available off the shelf (and likely to remain so for at least 2-3 years).. Is there a timing output on the GPS16x? (or are the serial messages synchronized in some way) So the 16x manual says. As far as I know, all of the Garmin LVC, HVC, and 5Hz versions of their receivers have a timing pulse output. The GPS18 series that I have was replaced by the GPS18x series. Some of their receivers have TIA-232-F (RS-232) Compatible Polarity which means exactly that. They do not provide RS-232 voltage levels so for my GPS18-5Hz, I had to hack together a little non-inverting level shifter (two transistors, some resistors, and a dual power supply) to convert the 0 to 5 volts into -12 and +12 volts. ___ 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] Inexpensive modular gps with 1pps
-Original Message- From: David [] So the 16x manual says. As far as I know, all of the Garmin LVC, HVC, and 5Hz versions of their receivers have a timing pulse output. The GPS18 series that I have was replaced by the GPS18x series. Some of their receivers have TIA-232-F (RS-232) Compatible Polarity which means exactly that. They do not provide RS-232 voltage levels so for my GPS18-5Hz, I had to hack together a little non-inverting level shifter (two transistors, some resistors, and a dual power supply) to convert the 0 to 5 volts into -12 and +12 volts. === I must have been lucky with my combination of 18, 18x and various PC serial port receivers, as I haven't needed a level shifter with either. But the slightly less than 3V from a different 3.3V GPS does /not/ register on a different serial port. Circuits: http://www.satsignal.eu/ntp/GPS-interface-1.png http://www.satsignal.eu/ntp/GPS-interface-2.png from: http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm -- 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] Inexpensive modular gps with 1pps
On Thu, Nov 15, 2012 at 4:30 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james === It looks idea, James, but ... with the 15 mm square patch antenna it seems deaf compared to similar devices with 25 mm antennas. Perhaps understandable, but I just bought one and it's been sitting for well over an hour and not yet acquired lock. The device I bought from China, sitting next to it, has been happily locked for that whole period. (As I'm running a test I don't want to unlock the other device). Just a caveat for someone considering using these devices indoors - size matters! 25 mm antenna device: http://www.satsignal.eu/ntp/NEO-6M-under-initial-test.jpg http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk all good points David. I originally had place mine close to a window to get a lock as it could not acquire any satellites in my home office otherwise. I don't have a south facing window and my office is on the first floor of a two story house. That may or may not have played a part but just placing it near the window and facing outside worked fine. I added the antenna (https://www.adafruit.com/products/960) and the connector (https://www.adafruit.com/products/851) and now I don't have to keep my RPi and gps near the window. What I liked about this one was it would interface with the RPi GPIO pins without having to use a converter from RS232 to 3.3v and I never considered a USB gps due to the inherent issues with USB and timing. Thanks, James ___ 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] Inexpensive modular gps with 1pps
From: james machado [] all good points David. I originally had place mine close to a window to get a lock as it could not acquire any satellites in my home office otherwise. I don't have a south facing window and my office is on the first floor of a two story house. That may or may not have played a part but just placing it near the window and facing outside worked fine. I added the antenna (https://www.adafruit.com/products/960) and the connector (https://www.adafruit.com/products/851) and now I don't have to keep my RPi and gps near the window. What I liked about this one was it would interface with the RPi GPIO pins without having to use a converter from RS232 to 3.3v and I never considered a USB gps due to the inherent issues with USB and timing. Thanks, James = Well, after 5 hours the Adafruit unit finally locked - must have been just the right combination of satellites! I was slightly surprised by the difference in antenna size. It would have to be placed near a window for normal use. Like you I have some puck antennas which I've used on other GPS devices, with the GPS 18 LVC being placed on the roof (it's not very sensitive), the GPS 18x LVC and the other units being placed indoors, some on a south-facing wall, but all on the top storey of a two-storey house. Having the extra antenna cable allows more versatility in placing the unit, but these are so small - even /with/ the computer, that it's a choice between antenna cable or Ethernet/power cable. The 25 mm antenna NEO-6M board I got also has 3.3V interfacing which, as you say, is a bonus. USB would suit as a source of coarse seconds if you needed a stand-alone unit for operation when out portable, although, as you will know, the Raspberry Pi also has a serial interface you can program for two of the GPIO pins, freeing up the USB ports for something else. Cheers, 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] Inexpensive modular gps with 1pps
jim...@earthlink.net said: ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. Garmin GPS-18x. The GPS-18x is the newer version. The GPS-18 (no x) is no longer in production. There are several versions. Check the fine print. The USB version doesn't have a PPS and the synchronization on the serial messages is crappy. (It was reasonably good on the -18.) Alternatives here: http://www.usglobalsat.com/s-18-serial.aspx -- 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] Inexpensive modular gps with 1pps
david-tay...@blueyonder.co.uk said: Well, after 5 hours the Adafruit unit finally locked - must have been just the right combination of satellites! I was slightly surprised by the difference in antenna size. It would have to be placed near a window for normal use. .. There is another variable to consider: cold start vs warm start. If it doesn't know the time or doesn't have a recent copy of the satellite orbit info, it has to search a lot harder to get locked up. When you get a chance, disconnect it for an hour and try again. I'm assuming it has a battery backup so it can keep track of time. Or watch the number of satellites it can see and compare that with other receivers in a similar location. -- 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] Inexpensive modular gps with 1pps
On Thu, Nov 15, 2012 at 9:02 PM, Jim Lux jim...@earthlink.net wrote: ALl good ideas.. but I was looking more for something a bit more packaged.. like a hockey puck with wires coming out. Me too, please. Something with a PPS, and an RS-232 output, withour soldering. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ___ 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] Inexpensive modular gps with 1pps
gha...@gmail.com said: Me too, please. Something with a PPS, and an RS-232 output, withour soldering. I don't know of any low cost no-soldering solutions. -- 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] Inexpensive modular gps with 1pps
On Thu, 15 Nov 2012 15:06:10 -, David J Taylor david-tay...@blueyonder.co.uk wrote: -Original Message- From: David [] So the 16x manual says. As far as I know, all of the Garmin LVC, HVC, and 5Hz versions of their receivers have a timing pulse output. The GPS18 series that I have was replaced by the GPS18x series. Some of their receivers have TIA-232-F (RS-232) Compatible Polarity which means exactly that. They do not provide RS-232 voltage levels so for my GPS18-5Hz, I had to hack together a little non-inverting level shifter (two transistors, some resistors, and a dual power supply) to convert the 0 to 5 volts into -12 and +12 volts. === I must have been lucky with my combination of 18, 18x and various PC serial port receivers, as I haven't needed a level shifter with either. But the slightly less than 3V from a different 3.3V GPS does /not/ register on a different serial port. Circuits: http://www.satsignal.eu/ntp/GPS-interface-1.png http://www.satsignal.eu/ntp/GPS-interface-2.png from: http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm None of those circuits would have worked for me. The GPS18-5Hz manual says 0 V to Vin, between 4 and 5.5 V (Asynchronous Serial, TIA-232-F (RS-232) Compatible Polarity) and as far as I know, most if not all of the other Garmin serial outputs are similar. The timing and polarity are RS-232 compatible but the levels are not. RS-232 traditionally requires a minimum of -3 and +3 volts, in between is undefined, and -12 and +12 volts is more typical to provide sufficient noise immunity for error free operation at high speeds and with long cable runs. In addition, since the serial output is Compatible Polarity, it is not inverted so it cannot be directly used with an RS-232 level translator because they all expect an inverted logic level signal. That is easy enough to fix with a single transistor inverter but still annoying. It is doubly annoying when you consider that interfacing it directly with a standard UART would also require an inversion. I gather than some serial ports, like those on many USB to serial dongles, will work with the nonstandard 0 to 5 volt levels but none of my equipment will. My temporary solution was to build a little two transistor level shifter so I can play with the GPS18-5Hz and decide if it is worth working with: http://www.banishedsouls.org/c2df3757f1/GPS18/RS-232.jpg On that board there is also a simple RS-232 to logic level driver so the computer can talk back to the GPS18-5Hz (I had to upload new firmware and configuration data.) and a shunt mode 50 ohm cable driver to unload the 5 pulse per second output. The shunt mode 50 ohm cable driver is rather power hungry but produces an exceptionally clean output. My current plan is to build an improved level translator so I can move the GPS18-5Hz to the peak of my roof and use a standard cat-5 cable for simple 12V power, bidirectional RS-232, and a clean 5 pulse per second signal. After I get an OnCore receiver that supports sawtooth correction, the GPS18-5Hz can feed a local NTP server instead of a GPSDO. ___ 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] Inexpensive modular gps with 1pps
Hi Not much of a market for that sort of stuff. Bob On Nov 15, 2012, at 5:59 PM, Hal Murray hmur...@megapathdsl.net wrote: gha...@gmail.com said: Me too, please. Something with a PPS, and an RS-232 output, withour soldering. I don't know of any low cost no-soldering solutions. -- 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. ___ 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] Inexpensive modular gps with 1pps
On 11/15/12 4:10 PM, Bob Camp wrote: Hi Not much of a market for that sort of stuff. Bob Big enough that Synergy Garmin have pricing for anywhere from 1 to 1000 units ___ 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] Inexpensive modular gps with 1pps
Hi ….. but not at the same sort of price as a consumer grade GPS. Bob On Nov 15, 2012, at 7:27 PM, Jim Lux jim...@earthlink.net wrote: On 11/15/12 4:10 PM, Bob Camp wrote: Hi Not much of a market for that sort of stuff. Bob Big enough that Synergy Garmin have pricing for anywhere from 1 to 1000 units ___ 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] Inexpensive modular gps with 1pps
The Sureelectronics board may be worth a look. RS232, USB and a claimed Time Accuracy of a rather optimistic 20nS. ian http://www.sureelectronics.net/goods.php?id=98 http://www.sureelectronics.net/goods.php?id=99 Date: Thu, 15 Nov 2012 14:59:09 -0800 From: Hal Murray hmur...@megapathdsl.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Inexpensive modular gps with 1pps Message-ID: 20121115225909.289b5800...@ip-64-139-1-69.sjc.megapath.net Content-Type: text/plain; charset=us-ascii gha...@gmail.com said: Me too, please. Something with a PPS, and an RS-232 output, without soldering. I don't know of any low cost no-soldering solutions. -- 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] Inexpensive modular gps with 1pps
jim...@earthlink.net said: Big enough that Synergy Garmin have pricing for anywhere from 1 to 1000 units I don't know of any GPS units with PPS that are both low cost and no soldering. There are several low cost units that come in a nice small package. But you can't just plug them into your PC. You have to provide power and add a connector. There are quite a few more units if you don't need a nice package. There are several no-soldering packages. I haven't seen one that is low cost. There are many low cost GPS devices that use USB without any soldering. They don't have PPS. -- 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] Inexpensive modular gps with 1pps
SparkFun? https://www.sparkfun.com/pages/GPS_Guide Great people to deal with -- they have a lot of information online for each module. Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of gonzo . Sent: Thursday, November 15, 2012 17:08 To: time-nuts Subject: Re: [time-nuts] Inexpensive modular gps with 1pps The Sureelectronics board may be worth a look. RS232, USB and a claimed Time Accuracy of a rather optimistic 20nS. ian http://www.sureelectronics.net/goods.php?id=98 http://www.sureelectronics.net/goods.php?id=99 Date: Thu, 15 Nov 2012 14:59:09 -0800 From: Hal Murray hmur...@megapathdsl.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Inexpensive modular gps with 1pps Message-ID: 20121115225909.289b5800...@ip-64-139-1-69.sjc.megapath.net Content-Type: text/plain; charset=us-ascii gha...@gmail.com said: Me too, please. Something with a PPS, and an RS-232 output, without soldering. I don't know of any low cost no-soldering solutions. -- 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. ___ 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] Inexpensive modular gps with 1pps
There seems to be a nascent market for small GPS receivers in the DIY drone hobbyist sector. I stuffed one of the modules from http://store.diydrones.com/category_s/10.htm (more info at http://store.diydrones.com/3DR_GPS_LEA_6_p/br-3drlea-6.htm ) into a small plastic project box and added a USB cable to the appropriate pins on the LEA-6H module. In this case I wanted NMEA data rather than 1-pps, but 1-pps is available as well. At the time I was looking, I didn't see a simple, ready-to-go receiver module that had an antenna at one end and a USB virtual COM port on the other. Fortunately the LEA-6H's USB output worked great when I added the cable. -- john Miles Design LLC -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts- boun...@febo.com] On Behalf Of Bob Camp Sent: Thursday, November 15, 2012 4:10 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Inexpensive modular gps with 1pps Hi Not much of a market for that sort of stuff. Bob On Nov 15, 2012, at 5:59 PM, Hal Murray hmur...@megapathdsl.net wrote: gha...@gmail.com said: Me too, please. Something with a PPS, and an RS-232 output, withour soldering. I don't know of any low cost no-soldering solutions. -- 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. ___ 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] Inexpensive modular gps with 1pps
-Original Message- From: Hal Murray [] There is another variable to consider: cold start vs warm start. If it doesn't know the time or doesn't have a recent copy of the satellite orbit info, it has to search a lot harder to get locked up. When you get a chance, disconnect it for an hour and try again. I'm assuming it has a battery backup so it can keep track of time. Or watch the number of satellites it can see and compare that with other receivers in a similar location. Yes, it's the cold start which is the problem in this case. According to the specification it should take 35 seconds (typical), but it needs a signal 20 dB higher than the tracking level to achieve this... Tried you suggested test, and re-acquisition was fast - yes, it has battery backup; a feature I now consider essential! Cheers, 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] Inexpensive modular gps with 1pps
Tried you suggested test, and re-acquisition was fast - yes, it has battery backup; a feature I now consider essential! Has anybody done any studies on acquisition time vs time since solid contact? -- 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] Inexpensive modular gps with 1pps
On Mon, Nov 12, 2012 at 10:28 AM, Jim Lux jim...@earthlink.net wrote: Looking for a non-surplus ( e.g. A current catalog item) gps module, with serial ( ttl or rs232) and 1 pps. Doesn't need high performance(100ns is fine), but should be $100 ish. Something with an integrated antenna would be great. ___ 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. i just used this to with a raspberry pi with good success. https://www.adafruit.com/products/746 james ___ 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] Inexpensive modular gps with 1pps
the Ublox LEA-6 is pretty cheap and has good performance. and the SUP500F that Brad has been doing group orders on has worked pretty well for me. eric On Mon, Nov 12, 2012 at 10:28 AM, Jim Lux jim...@earthlink.net wrote: Looking for a non-surplus ( e.g. A current catalog item) gps module, with serial ( ttl or rs232) and 1 pps. Doesn't need high performance(100ns is fine), but should be $100 ish. Something with an integrated antenna would be great. ___ 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. -- --Eric _ Eric Garner ___ 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] Inexpensive modular gps with 1pps
Hello You could have a look to the Trimble Anapala and Silvana. http://www.trimble.com/embeddedsystems/antenna-companion-modules.aspx Regards Luc Le 12 nov. 2012 à 19:45, Eric Garner garn...@gmail.com a écrit : the Ublox LEA-6 is pretty cheap and has good performance. and the SUP500F that Brad has been doing group orders on has worked pretty well for me. eric On Mon, Nov 12, 2012 at 10:28 AM, Jim Lux jim...@earthlink.net wrote: Looking for a non-surplus ( e.g. A current catalog item) gps module, with serial ( ttl or rs232) and 1 pps. Doesn't need high performance(100ns is fine), but should be $100 ish. Something with an integrated antenna would be great. ___ 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. -- --Eric _ Eric Garner ___ 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.
