All of the discussion about metal film resistors and a pF here or there of
stray capacitance is interesting, but the symptom sounds to me a lot like a
cold solder joint.

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"John A" wrote in message
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"Dave" wrote in message
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What do you do for resistors if you can't get carbon composition in the
ratings you need?

Do what the professionals do - use film resistors. Concerns about
inductive
effect at HF are greatly exaggerated. There are rarely as many "turns" as
often suggested. ( cf. Radcom Jan 2007, p58, fig 1! )


where can I get carbon composition resistors these days?

They are still available. Typically, Farnell offer 220R to 4K7 at 1W -
but
they are quite expensive.


John A