HW-101 The Saga Continues

[Mark Graalman WB8JKR]

  Rich,

  The grid of V14 is 3395.0 Khz I.F. signal, not audio so a
.33 cap will kill the oscillation along with the signal.

Have you tried subing that tube? I wonder if there is a bad
bypass cap in the bias line between stages allowing some unwanted
coupling via the bias path.


> At this point, we are going to take a .33mF mylar and run it across
> the grid resistor of V14 (I think...that may be wrong as I don't
> have the schematic in front of me...this is the tube that we changed
> the grid resistor from 470 ohms to 75 ohms, per Mark's mods).
> According to our calculations, this will have enuff Xc (around 84
> ohms at 6kc, which is what the howl oscillates at) to hopefully
> swamp the oscillation and eliminate it.

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