[time-nuts] FTS125 GPS Module

[SAIDJACK at aol.com]

Yes, I am sure, depends on the firmware revision and configuration  
settings. Don't want to name any names here though. Secondary firmware can  detect, 
and prevent this behavior once you know it exists, and what makes it  
happen.
 
That's part of what makes the difference between an NCO and a real GPSDO.  
With an NCO such as the FTS parts, you get a simple analog PLL that has no  
smarts or intelligence, and a GPS receiver that can get hung up when in 
holdover  for excessive amounts of time.
 
There is ample evidence in the time nuts archives that the Trimble GPS have 
 problems getting a fix in the first place after power-on. Several users  
reported that here, and in other places.
 
Also, now we are being told that Trimble discontinued the Mini-T, and we  
see lot's of customers panicking and looking for replacement solutions as  
Trimble seems to not want to offer a replacement product and is giving a  
last-time-buy notice. Sorry for those customers, gives an opportunity for others 
 to move in.
 
bye,
Said
 
 
 
In a message dated 6/28/2012 12:21:27 Pacific Daylight Time,  
azelio.boriani at screen.it writes:

>other GPS receivers have the same exact problems when left  in
>holdover for hours or more

Are you sure? Never seen that  behavior on a Trimble, Motorola/iLotus,
uBlox, Sanav or SkyTraq   receiver, only on NavSync.

The locking algorithm of the FTS250 (and  maybe the FTS125 too) is a
National LMX series PLL chip (I can't remember  the exact part number, have
to check with the FTS250 COO we  have).