Hi Mike,
Quite a few digital readouts will work on the FRG-7. The problem is in getting an accurate readout down to 100 Hz.
Info on several counters can be found in the Files section folders 5 & 6.
An offset counter counting the VFO frequency will be at the mercy of the H. GEN. accuracy. If the HG 1 MHz crystal is off by 100 Hz the H.GEN output will be off by 300 Hz on the lowest band and 3,200 Hz on the highest band. This inaccuracy will carry through using most offset frequency counters.
The ESP DD-103 can hold corrected offsets for 32 bands so it could be set to be accurate on an FRG-7.
I would check your H.GEN for accuracy before buying a display. If it is dead on any of the counters in Folder 6 would work well.
My plan is to see if the HG crystal can be modified to use a trimmer to net it to 1 MHz. If it can't I intend to replace the crystal with a TCXO module that can be netted to 1 MHz. The TCXO may not work properly with the Harmonic Generator (HG) circuit as is.
73
Roger VE7LB
