Thank you to Ron Ellis, and Tom Marvracic. I did speak with Bob Novak who said an early Logictrol servo would be very similar. He no longer has any Bonner, Larson, or RS Systems documentation. The 4RS is now working, but it's a bit itchy, so no doubt I will have to go and change every electrolytic capacitor in the servos (5 ea) and receiver (4 ea).
As much as I like this radio, it has to go on the auction block to raise funds for the club who gave it to me, so if anyone is interested, please feel free to contact me.
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