Hi..I'm Graham VE3WGW residing on the shores of Lake Eire in Canada.
I have just built 2 of the prog rocks.
Did the change of the 39k to 27k in the filter circuit to get closer to .33v.
I installed TCOX's in place of the 27mhz crystal.
After setting the calibration correctly. Mine set to 27,000,025 to get it correct.
They have been sitting on 10 mhz for the past number of hours.
Not moved more than .3 hz......
I have a gps calibrated oscillator... so it is dead on.....
One of them is going to be used in a Kendecom 220 mhz repeater as the RX crystal died... At first tests everything is excellent..
The other is going to be the crystal bank in a GE MSTR II ... for 8 chans on 6 meters.
Heck... The prog rock plus the TCXO is less than the price of 1 crystal !!