John?

The cathode is a low impedance circuit (750 ohms compared to 80K for G1) so I would think that measuring there would have less an effect on the frequency stability of the oscillator.

See definition of Logic below!

Jim

Logic: Method used to arrive at the wrong conclusion, with confidence. Murphy

On Sunday, September 21, 2025 at 12:30:19 PM CDT, jphutch60bj <[email protected]> wrote:

Specific to BC348-Q converter tube VT150 aka 6SA7.

To sniff out the actual frequency being generated by the Local

Oscillator circuit, would that be best measured from the Cathode pin #6

or from the Grid 1 pin #5 ?

Don't want to shift the frequency, or at least minimize it, through a

25pF cap to my frequency counter? Grid or Cathode to ground?

I need to see ~15mV for my counter to work.

Thanks for your 2 cents.

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