Mark, Azelio and Björn, On 05/14/2012 06:33 PM, [email protected] wrote:
Mark& Azelio,Or even 10V into 50ohm, 20us... See figure 3-4 in ICD-GPS-060. http://www.navcen.uscg.gov/pdf/gps/ICD-GPS-060B.pdf More modern 3-5.5V into 50ohm, 20us. http://contracting.tacom.army.mil/majorsys/jab/DAGR%20Interface%20Specification.pdf Above are two standards demanding short skinny 1PPS pulses. Are there any other standards with distinct shape requirements on 1PPS pulses?
You need to look at MIL STD 188/155 which if I recall things was initially formed in the 60thies.
An AccuBeat presentation actually says that the PPS was originally defined in it.
The MIL STD 188/155 is actually a 10 V peak level, so it was much hotter than we are used to know. It specified 5 MHz as base frequency, or power of 2 multiples (10, 20, 40 MHz... ).
It was later reformulated in the PTTI spec, which ICD GPS 060 is a derivate. The 50 ns rise and 1 us fall slopes comes from that spec.
I was not able to find MIL STD 188-155 on the net right now, but I have been able to download it before, so if someone is a more lucky it should surface. I should have my download somewhere.
Cheers, Magnus _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
