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#26 pre amp

Front panel

If I understand you correctly....take of the Front Panel........Drill the appropriate hole in the Chassis to mount the POT........then Drill a much Larger hole in the Front Panel (just slightly larger than the Nut holding the Pot)...... replace the Front Panel... and with the right sized Knob it should cover the hole

I need to reduce the fron plate to install the pot, who knows how I can do it?
 
Wood drill works😉
 

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Yes my chassis front plate have 10mm is too broad/widht and can't fix the pot.

Hello Felipe,

I had the same predicament with my Gold Point attenuator. I took mine to a machine shop and have it tapped (M10 x 0.75) from the inside all the way to the front so that I have the full lenght of the shaft on the front side.

Or have it "counter bore" 5mm from the inside is another option too. This way, the plate holds the pot not the chassis as it will be a pain to install another bracket on the chassis from my layout.

Abe
 
Pics just for fun, one measuring voltage across 100R to adjust CCS mA, voltage plate both tubes, square wave both tubes.🙂
 

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