MC85.1

     A.  I couldn't work vox properly with the PC-1A because
I couldn't null deep enough the bridge.  VR1 was partly
nulling at the far end of it's position.  Adding a 1.5k ohm
in parallel with R5 (or alternatively just changing R5 to a
single 470 ohm resistor) brought the null to the mid-position
of VR-1.
     B.  Although the null is now centered, it was not deep
enough.  Adding on 0.1 uf disk capacitor in parallel with RF
balanced the reactive component of the bridge, the null
became extremely sharp!
     C.  An addition of a high pass filter to the patch that
gives the same effect as the "low cut" position on the MC-85
microphone was "very helpful" when the PC-1A was connected to
the SSB HF ring.  The filter is simply made of a 10K ohm
resistor and an 0.02 uf capacitor.  (see it on the modified
scheme (next month)).
With all the changes I made to both the PC-1A and the MC-85,
I'm most satisfied and I would very much like to hear your
remarks (maybe published in the I.R.I. too!).
                             RELAYED  BY   N0KGX...GENE