[time-nuts] frequency reference for portable operation

Bob Camp lists at rtty.us
Tue Mar 12 00:54:45 UTC 2013


Hi

CDMA should be good to ~0.0001 ppm when running normally. The driver there is holdover rather than transmit accuracy. The carrier comes from the same source, so the accuracy is "free". CDMA is all over the place….

A cheap GPS receiver sounds like a much better solution for NTP. Far more trustworthy. 

Bob

On Mar 11, 2013, at 7:54 PM, gary <lists at lazygranch.com> wrote:

> http://www.evrytania.com/lte-tools/lte-cell-scanner
> claims the LTE reference is good to 0.05PPM.
> 
> I can verify that 739MHz and 751MHZ are the only LTE frequencies I found in use in the 700MHz band in the San Francisco Bay Area.
> 
> If you want to use the software, I suggest trying 739MHz and 751MHZ first. Get the calibration factor, then start the search with a reduced "p" parameter. The initial search assumes a ppm error in the SDR of 120PPM. However, once you get the calibration factor, you can used the reduced PPM parameter which substantially improves the search speed.
> 
> I haven't found a program to actually use the LTE frequency reference for say NTP. Maybe satcom Dave has time on his hands. ;-)
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.




More information about the Time-nuts_lists.febo.com mailing list