Iain Churches wrote:


So low (or no) stability margin. The oscilaltion can be cured with a
Zobel network. But one should really find the cause:-)



It was fixed by adding the 220p cap across the feedback resistor the
circuit diag showed but wasn't fitted, maybe to improve the HF response.

I think the main cause was the crap output TX's having too much phase
shift at HF :-).

--
Nick