Big Hum on "treble" pot on my 5e8-A

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martin manning
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Re: Big Hum on "treble" pot on my 5e8-A

Post by martin manning »

pampeo wrote:Hello
replace the yellow wire who make loop in front of the filament wire and the hum was decrease ;) good news
But is still here ...and I don't have an idea to solve !
nobody have an idea ?
thx
In general I think you have too much wire in there. Look at this picture (it's a 5F6-A) and compare it to yours... shorter filament wires, and all the leads from the board to the tube sockets and controls are pressed agianst the chassis.
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Cliff Schecht
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Re: Big Hum on "treble" pot on my 5e8-A

Post by Cliff Schecht »

Here's my 5E8A build that I finished as of maybe 2 days ago. I still haven't even had time to fire it on yet fully. The power transformer was a 12 pound beast I got on eBay for $5 that spits out closer to 600V unloaded after the 5U4's (about 550V loaded). I built a little (well, big) BJT-based reference circuit to elevate the center tap by ~125V to knock down the B+ but other than that nothing too unusual. I can't stand those cramped Fender chassis either though so I drilled this bastard out by hand and made the board from some scratch particle board I had laying around. My first time using eyelets too :D.
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pampeo
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Re: Big Hum on "treble" pot on my 5e8-A

Post by pampeo »

nice pics guys
I will check the stage who hum by removing one per the preamp tube and rewiring the hum stage
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