> Mine just went out in one of my 86's - also looking for info.
>
> Bob, AK6R
The original diode was an exceptional diode. Long carrier lifetime
with high voltage rating....yet cheap. Ameritron used to use them
also, but I used two diodes cathode-to-cathode in series...with 400
volts of bias.
Since the original diode is no longer available, the circuit was
modified to use four lower voltage diodes in series.
If you pick a diode, pick one with the longest possible carrier
lifetime. You need at least 3 or 4 uS for 160 meters. Using multiple
diodes in series (or opposing directions in parallel for transmitting
diodes) is better than single diodes for many reasons.
I'd have a look at the Ameritron circuit and see if it can be adapted
into your ETO circuitry.
73, Tom W8JI
W8JI@contesting.com
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