In article ,
Edmund H. Ramm wrote:
In ron_ayling writes:

[...]
the detector pre amp valve was originally an AR8 which is a
triode plus two diode and this has been replaced with a 6AM6
which is a straight RF Pentode!!!
[...]

And two semiconductor (shudder) diodes weren't sneaked in
below the chassis?

Oh yes, and what about using a 6AV6? Two diodes, and a triode with plenty
of gain. It's got 2 pF grid to plate which is annoying, but you can do worse.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."