>
>Around here Bill, KC2IFR (iirc) just put one on the air - AM, 75m.
>
>One of the things he found was that the input is a 350 ohm resistor...
>which makes matching to solid state trancievers a bit dodgy... He ended
>up using a matchbox between his rig and the Johnson...
>
>He says he tried changing it to just a 50 ohm resistor and it did not
>"work"... seems like it should have, but I wasn't there.
A 200-ohm grid terminator fed through a 1 to 4 bifilar transformer should
work ok with c. 100w drive.
>
>His choke was shorted out - he put a different choke in the hole...
>
>It sounds pretty good so far on AM... but he says he'd rather have
>a different linear knowing what he knows now...
>
The original circuit can be improved. There is no such thing as a
perfect commercially mfg amplifier.
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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