[Johnson] Ranger keyer

[Jim Brannigan]

You don't say whether the keyer worked and stopped or this is a new 
acquisition.
I had a similar problem and traced it to a mis-wiring in another part of the 
radio.

Jim

> The keyer circuit will not adjust at all on my Ranger 1.
>
> Adjusting R39 does nothing.  Bias voltages are correct.
> If I short C89 (.047) to ground the unit will key.  Plate voltage @ pin 6 
> of the 12AU7 is 350 volts
>
> Adjusting R39 through full range causes pin 2 of the 12AU7 to go 
> from -28.7 volts to -66.1 volts.  Pin 7 of the 12AU7 goes from -59.7 
> to -59.9 (basically doesn't change)  It seems to me that the voltage at 
> pin 7 would have to approach zero to fire the keyer.
>
> I have checked all resistors and capacitors on the keyer circuit and they 
> all seem within tolerance.  Tubes replaced with known good ones.
>
> What am I missing or should be looking for.
>
> Thanks Chuck Hurley  K1TLI
>
> Everything else works fine
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