Those 6146's look nice in there. I won't argue idling current and fidelity, it is a communications circuit. Just go by the tube manuals. With 6146 there is no need for ceramic sockets because the plate is on the glass and the highest voltage on the socket is the G2 voltage.
Tim WA1HLR opined about the cause and solution of the arcing back in 2009. Makes a good case for adding spark gaps to the primary of the mod transformer too. Amazing what you can find in the archives on here
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Al VE3AJM
Title: Re: modulator tubes in apache
Post by: Tim WA1HnyLR on January 29, 2009, 01:34:46 PM
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We must ask ourselves, why do 6CA7s crapout in the modulator of the Apache or flash over at the socket? ... De Tim WA1HnyLR
In the case of the Czech bootleg amps, an 800V plate supply, plus the square wave and distortion abuses of guitar players, made the sockets arc from Plate terminal to another terminal or GND. The tubes took the volts, but only the ceramic sockets worked. The EL34's in question would have been UK-made or Russian/Tesla brand. It may have no bearing on this application of transmitters and China tubes.
