Magnus et al, The TM3 is currently undergoing final software tweaks and should be available by February (but you know how software schedules go....) They will be slightly less expensive than the M12M receivers.
The basic chip is the u-NAV. There are a couple different versions, although the -01 will be the initial release. This receiver communicates in both SiRF binary (yes, it's officially SiRF binary now) and NMEA protocols at 4800, 9600, 19,200, and 57,600. It also has onboard FLASH so that you can save setup information. I'll keep you guys informed as I learn more. Randy Warner Senior Applications Engineer Synergy Systems, LLC [EMAIL PROTECTED] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Magnus Danielson Sent: Saturday, December 30, 2006 8:53 PM To: time-nuts@febo.com; [EMAIL PROTECTED] Subject: Re: [time-nuts] Signav GPS timing receivers From: Dr Bruce Griffiths <[EMAIL PROTECTED]> Subject: Re: [time-nuts] Signav GPS timing receivers Date: Sun, 31 Dec 2006 15:59:45 +1300 Message-ID: <[EMAIL PROTECTED]> Bruce, > Has anyone used any of the following signav receivers for timing purposes. > They claim to actually correct the sawtooth error in hardware. > > http://www.signav.com/index_files/PDF_Files/New_Brochures/SigNav%20TM3 > -01%20Brochure%20V1.2.pdf > > http://www.signav.com/index_files/PDF_Files/New_Brochures/SigNav%20TM3 > -02%20Brochure%20V1.2.pdf > > http://www.signav.com/index_files/PDF_Files/New_Brochures/SigNav%20Bro > chure%20TM3%20Evaluation%20Kit%20V1.1.pdf > > The receiver oscillator is disciplined to "eliminate" sawtooth correction. > The 2nd has a 10Mhz 1E-8 stability reference frequency output. Considering the options, I'd say that this is basically a modernized version of the Allstar/Superstar receivers. Most probably it is the Zarlink GP4020/GP2015 chipset at work. The other posibility (uNav) does not neatly match frequencies and the GP4020 has two extra divide counters which makes the clock output on the TM3-02 very easy to acheive. The GP4020 also provides a handy SPI interface so hooking up an external SPI DAC for EFC is trivial. The GP4020 has a refined PPS output compared to the old GP2021, but it is an interesting "hack" ontop of the old core, something which could be used to enhance older receivers if one wishes. That way the 7 second beating pattern can be avoided. Naturally, that 7 second pattern is very predictable and could be included in negative sawtooth output if you where going down that route. The core clock is at 40 MHz in those, so a stepup from 10 MHz is trivial (and indeed how it is done). Also delivering 10 MHz and 1 kHz outputs should not meet any interesting issues at all. It is interesting how they are targeting the M12+/M12M market. Looks like a sweet deal. If you look down their webpages, they seem to have put alot of their effort into the backend processing, including Kalman filtering, doppler processing to dead-reckoning moving vehicles with too few satellites in view etc. All quite doable on the old receiver cores as such, but takes bigger footprint in software. Looks quite interesting. Randy said earlier that he where going to sell them, but they don't seem to have appeared on their web. What is your asking for one of these? I'd sure like to run it against some other stuff here. PS. My newly arrived Symmetricom 56k locked up this evening. There's now another GPSDO in the house featuring both Rb (a TEMEX Rb) and OCXO (OSA 8666). Cheers, Magnus _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
