I was given a FT726R with the 6 2 and 70cm modules, the maintenance
manual, and a few spares. As I was adding a CTCSS tone board it seemed
like a good idea to check the adjustments and alignment. Unfortunately
I've found that the TX balanced modulator doesn't balance. Checks were
made for noise on the 13.8 VDC and regulated 8V (which powers the
uPC1037H modulator) and these lines are quiet. The maximum carrier
suppresion I could get from adjusting VR05 was 25dB, far short of the
specified >40 dB. There is a good voltage swing on VR05, but the
voltage on pin 6 of the modulator changes very little. I suspect it's
Can replacement uPC1037H's be found.
If I get this sorted then I'll ask about how to run it duplex and do
the Doppler correction on SSB or CW.
Ron VE8RT <ve8rt(a)yknwt.ca>