[Milsurplus] Advice Please: Frequency stabilizing a 80M ARC-5 transmitter

[Mack McCormick]

I have an ARC-5 transmitter that I am using as a VFO for the BC-375 to
prevent FMing from the BC-375 MOPA oscillator/PA.

The ARC-5 exciter is working great except for frequency stability. The peak
carrier frequency starts about 1 kc low and after about 1 minute is about 1
kc high. Not really a big deal except it drives the SDR folks crazy when
I'm on an AM net.

The 1626 oscillator is exceptionally well regulated using a FET in the
external power supply. It is rock solid.

*Do you have other ideas on how I might further improve frequency
stability? *I built a crystal oscillator but it does not have enough drive
using a 12A6 vacuum tube to drive the 1625's above about 5 watts. I'm
still troubleshooting this circuit.

I need about 20 watts out of the 1625s.

73,

Mack
W4AX
https://www.qrz.com/db/w4ax
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