[ARC5] GO-9: Cathode Mod Questions and...

[David Stinson]

  Thank you everyone for your replies to this thread and excellent 
information.

As of now, I'm still with the original solution.  Changing from 2000 
ohms to lower taps (1500-1000-500) did not improve things; at the 500 
tap, the rig would only modulate to about 10% before flat-topping and 
distortion.  I can get near 100% clean modulation with the rig 
throttled-back to 70 watts or less.  If I ever find a larger-core audio 
transformer with similar impedance taps, it will be interesting to try it.

Still haven't added yet another transformer to change the grid-blocking 
supply and I won't if I can help it.  I have added lights to warn of an 
improperly-wired AC outlet.   Working on installing a Powerstat 10B 
variac for internal control of the transmitter power.  Still more to do.

GL OM ES 73 DE Dave AB5S