Recently picked up a well used Clipperton. Has 4 new 811A's that I plan on
using with the lower plate voltage. Have some questions that hopefully can
be answered here.
1. I assume the 9.1 Zener is used for idling plate current via the relay on
TX.
2. Also assume the 47k resistor via the relay is for cutoff bias on RX also
via the relay.
3. I used a 47ohm/220pf combination on each grid to ground as did Collins in
the 30L1. That should get 4.7 volts bias on each grid with the thought that
with about 1700 volts on the plates some bias would be needed.
4. Why no filament center tap. If I need to, can I use a 22 ohm resistor
from each side of the secondary to make one ??
5. What is the recommended safety for spikes? I used 10 ohms in the B+ line,
are back to back diodes still the cure on the B- ??
6. Tuned input, can anyone send me the values needed for 10-160 especially
160 as the HB has 10-80 that I guess would be OK.
7. Can a parallel tuned circuit be used on the input rather than a pi. or is
the bandwidth too narrow without a pi?
Thanks for taking the time to read this........73
Ed W3NR
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