OE1IFM

Today we did some tests on the Navsync CW25-TIM module. Thanks to OE1DMB who supported me on that with his test equipment. Using a
R&S Spectrum Analyzer and a Datum Rubidium source as a frequency reference we had a look at the accuracy of the Navsync module.
The result is: This little module shows an outstanding performance. We don't know exactly how they do it, but the unit has an frequency error
of less than 0,05ppm WITHOUT being synchronized to the GPS system.

Here is what we did:

·         We attached the Datum Rubidium source to the R&S Analyzer as an external reference

·         We turned on the Navsync module WITHOUT a GPS antenna

·         The frequency reading was 29.999.999,60MHz – so it was off 0,033ppm

·         We put some cooling spray on the module and it drifted about 3-4Hz up

·         Within 10sec (much faster than re-warming) it came back to less than 1Hz off

·         We attached the GPS antenna and the frequency reading was 30.000.000,00MHz

Obviously the unit stores correction factors from the last synchronized period in flash and uses them for the next startup.

When the unit was in sync, we were not able to measure the frequency error with our equipment.

This result proofs that the Navsync CW-25TIM does exactly what I need for the beacon project. It delivers a highly accurate

LO frequency for less than US$70 including timing and location information. I can move forward with the design!

Find out more about the BeaconTNG procect here!