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If those Stackpole switches were easier to find, I would change the AM-FM/SSB switch to add the Grid bias on sideband only, but then again I don't use AM any way. nThe juice ain't worth the squeeze.

Negative 8vdc will be my target for bias then. More is not always better! Adding the few components for the grid bias voltage will be easy on the back side of the circuit board containing the tube socket traces. (See photo)[ATTACH=full]23391[/ATTACH]

It looks like my only option for the input tune circuit will be tapping into the back side of the relay circuit board trace(See pic with pointer)-interrupting the coax from the relay to the tubes cathode (pin 3). [ATTACH=full]23390[/ATTACH]

If the cut and try coil and trimmer cap are tucked in behind the rear tube and in front of the transformer, is it likely there will be any interaction/interference RF wise from the transformer windings and/or proximity to the high plate voltage?[ATTACH=full]23393[/ATTACH]

<blockquote data-quote="Dmans" data-source="post: 623892" data-attributes="member: 49046">If those Stackpole switches were easier to find, I would change the AM-FM/SSB switch to add the Grid bias on sideband only, but then again I don&#039;t use AM any way. nThe juice ain&#039;t worth the squeeze.Negative 8vdc will be my target for bias then. More is not always better! Adding the few components for the grid bias voltage will be easy on the back side of the circuit board containing the tube socket traces. (See photo)[ATTACH=full]23391[/ATTACH]It looks like my only option for the input tune circuit will be tapping into the back side of the relay circuit board trace(See pic with pointer)-interrupting the coax from the relay to the tubes cathode (pin 3). [ATTACH=full]23390[/ATTACH]&nbsp; If the cut and try coil and trimmer cap are tucked in behind the rear tube and in front of the transformer, is it likely there will be any interaction/interference RF wise from the transformer windings and/or proximity to the high plate voltage?[ATTACH=full]23393[/ATTACH]</blockquote>

[QUOTE="Dmans, post: 623892, member: 49046"] If those Stackpole switches were easier to find, I would change the AM-FM/SSB switch to add the Grid bias on sideband only, but then again I don't use AM any way. nThe juice ain't worth the squeeze. Negative 8vdc will be my target for bias then. More is not always better! Adding the few components for the grid bias voltage will be easy on the back side of the circuit board containing the tube socket traces. (See photo)[ATTACH=full]23391[/ATTACH] It looks like my only option for the input tune circuit will be tapping into the back side of the relay circuit board trace(See pic with pointer)-interrupting the coax from the relay to the tubes cathode (pin 3). [ATTACH=full]23390[/ATTACH] If the cut and try coil and trimmer cap are tucked in behind the rear tube and in front of the transformer, is it likely there will be any interaction/interference RF wise from the transformer windings and/or proximity to the high plate voltage?[ATTACH=full]23393[/ATTACH] [/QUOTE]

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