[Milsurplus] Attn Smart People: Exciting Exciters

[David Stinson]

Back working on the 150W Peak Bendix 430 AM transceiver.
https://photos.app.goo.gl/Tz7vm1i9MLushNv47
It's crystal controlled.  I'd like to drive it with an
sig gen that will deliver 20V PTP into a Hi-Z load.

Below are diagrams of the driver stages, both 12BY7,
one from the Bendix (simple transmitter) and one
from the Drake T4.

The Drake stage is grid-block keyed by grounding
the bottom end of R22, removing the negative
blocking bias.  The Bendix uses B+ keying
and "protects" the finals from no drive by
using low screen voltage.

I want the 12BY7 in the Bendix to accept the
sig gen output, so I'm thinking:

Remove the 150 pFd C80 (effectively an RF bypass
when using the generator).
Increase R50 to somewhere north of 50K.
Insert a cathode resistor of about 100 Ohms,
bypassed by .0047.
Drive the grid of the 12BY7 through a DC blocking cap.

OK Smarter-than-me people, what do you think?

TNX OM ES 73 DE Dave AB5Sz

Bendix Skipper:
https://photos.app.goo.gl/maBJE63zMP5kDCty7

Drake T4:
https://photos.app.goo.gl/jTP3zq4R8KxvabrF7

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