Scratchy Guitar Volume Pot Problem

matttornado

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A valve with higher grid current than normal; not necessarily a fault per se, just makes it problematic in some applications.
Or a low anode voltage, eg much below 100V, perhaps due to anode or cathode resistors being wonky.
OK thanks!
 

matttornado

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Could it also be a bad solder joint? I already found one at V2 after putting my amp back together not too long ago (see link to post above). It was causing a static sound even with no guitar cord plugged in.
 

Chris-in-LA

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matttornado

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Check your lead dress. My 5e3 was doing the same thing. I fixed it by moving the V1 leads away from the heater wires. I also shortened a few leads where possible.
cool advice! thanks.
i’m gonna take look today and see what I find.
 

matttornado

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Alright. I had a chance to poke a round a bit and take some measurements. No DC present on guitar cord when plugged into amp.
I did not measure any DC at the any of the amps controls.

I took a chopstick and poked around everywhere and the amp stayed quiet - no pops static or scratchy sounds when moving wires and poking at resistors and caps, The only time i heard noises are when I touched some pins at the tube sockets which is normal as you would hear doing a "click test".

So I then cleaned the amp's input jacks and speakers jacks, atenuator's jacks and speaker cab's jack and re-tested.

It was better so I then cleaned the guitar's volume with some Deoxit and now it's a lot better.
 


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