[time-nuts] M12+ phase jump due to WAAS/EGNOS DGPS corrections?
Brooks Shera
ebs at wildblue.net
Sat Apr 22 17:56:22 EDT 2006
I received the note below from Ernie Peres in Germany which reports an effect consistent with an occasional phase jump in the 1 PPS output from a M12+ rcvr, perhaps related to DGPS corrections. The DGPS sats Ernie sees from his location are part of the EGNOS system.
The DGPS sats visible to me (sats #35,47 according to my Garmin V) are part of the WAAS system and I haven't noticed the phase jump effect with an M12+.
I wouldn't really expect to since the M12+ is not WAAS/EGNOS "enabled".
However, something more subtle might be occurring. I wonder if anyone else has noticed such an affect or has any ideas.
Brooks
------------------note from Ernie----------------------------
.....I am using a Motorola M12+ timing GPS eng board to drive the W5OJM controller board and the high prec OCXO. I have also bought a Garmin V handheld unit just for playing around and noticed that it displays " new " sats.....ie nbr 33 and 37. but the signal bar for this sats were gray instead of black on the display.
Later I learned that this new sats are the AOR-E sat nbr 120 and the ARTEMIS sat nbr 124, and also noticed that sat 33 is transmitting DGPS signals because the
GARMIN V / WAAS enabled / receiver displayed " D " letters in the signal strength bar. Also the TAC32 program displayed DGPS received and station ID "0000" age 0.........
When I see this sats on the GARMIN receiver the same time your GPS controlled board indicates a phase jump... I am using DG4RBF software to plot EFC and phase error......
Did you heard similar situation?
I do not know if this 2 sats are visible from the US but it should be because the position from my home / Frankfurt/M, Germany/ AOR-E EL... 28 deg. and
AZ.... 214 deg. the 37 sat ARTEMIS nbr 124 El...27 deg AZ....164 deg.
Also I have built other type of GPS controlled OCXO the so called "analog" version where the JUPITER GPS eng board 10kHz signal is PLL-ed the OCXO, and
also noticed on the EFC voltage a small variation....
Did any other person reported similar problem?
Based on the internet info this WAAS not yet fully operational. It is just a testing procedures ???????? or what is the future of this kind of OCXO locks?
Best regards,
Ernie HG5ED
------------------------end of Ernie---------------------------
More information about the time-nuts
mailing list