Hi, Sverre,
I just uploaded my implementation of Erik's design, including the code. You are welcome to grab that and try it to see if there is any difference. Though you did not implement the hardware phase detector, my code is not using that so it should not make a difference. I have been playing with this since last fall, and made a couple of mostly cosmetic changes to the display routines. Schematics, pictures, and parts lists included.?
I am still having a 'hang' issue with the display stopping after some apparently random amount of time. I think it has to do with recovery from GPS loss of signal, but have not positively confirmed that.?
73,
Bill
N5BIA