Re: Filter problem

Am 13.06.25 um 22:54 schrieb john larkin:

There is an inductor in the anode circuit, which resonates with the
valve capacitance (and a trimmer) at the output frequency.

There's no Miller effect only if the grids are zero impedance to
ground at 150 MHz.

There is no Miller effect when there is no voltage gain between
grid and anode that could be fed back via Cga. A shorted grid
just shorts the feedback. There is also no feedback when input
and output frequencies are really different or if the voltage
gain of the input device is kapputted by a cascode stage.
Cheers, Gerhard