Does anyone have any info on the OXCO in the Nortel/Trimble NTBW50AA-17
GPSTM receiver? The OXCO is labeled as Trimble 34310-T. I see some Trimble
34310-T oscillators on Ebay with pinouts labeled, but no other info.
Specifically, I'd like to know the EFC characteristics for it. I'm thinking
I've been using one for over a year. They take 12V to power, and they have a
VRef output around +6.25V, which implies an EFC range of 0-6V. Unless you get
one that's aged out, an EFC range of 0-5V should be fine. The VRef has a bit
of 10MHz on it on mine. All in all, it seems to be a good
Time-error would be rings for sure.
Doppler errors could also behave with these rings, but there is a much
more complex scenario of ground speed and angle of observation. As the
transponder passes under the satellite-earth line there is no
observeable doppler, just like a train passing by has
Hi
All of the OCXO’s in the GPSDO’s pull 100’s (or more) times the pull of a Rb.
The firmware that they have on that board for the OCXO is going to need some
serious tweaks to get it to work properly with an Rb. The GPSTM is not as tweak
friendly (no filter changes allowed) as some of the
Have you checked your X72 to see if it has the 1 PPS discipline option?
That would be a lot easier (and probably better) than your proposed
transplant.
Ed
On 8/22/2014 12:39 PM, Dave M wrote:
Does anyone have any info on the OXCO in the Nortel/Trimble NTBW50AA-17
GPSTM receiver? The OXCO
Bob wrote:
The GPSTM is not as tweak friendly (no filter changes allowed) as
some of the other GPSDO's.
And that is a major problem. The correct filter settings for a Rb
local oscillator are very different from the settings for an OCXO,
which in turn are different from the correct settings
You can probably find links to all of the data from the Duncan Steel Blog.
You might start by looking at the questions the group has posed in an open
letter to the ATSB and Inmarsat. Frankly, the data Inmarsat released appear to
be rather scant and some believe to be doctored not RAW.
I
