Power transformer wire grouping help

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Bieworm
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Re: Power transformer wire grouping help

Post by Bieworm »

"If" you solder to the pots directly there is something important to consider. The pot should be dialed to zero or to max. It's important the wiper is free from overheating because the carbon might be damaged and ruin your brand new pot.
Its just better practice not to solder to the pot housing. I've seen people solder a ground buss at the pots, but with legs to the grounding lugs of the pots, so the buss is like 1/2" in offset from the pots
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Re: Power transformer wire grouping help

Post by JMPGuitars »

TriodeLuvr wrote:
Wed 03/17/21 12:53 pm
If you decide to change it, you will need to remove all connections that are wired to the ground bus. You would need to instead connect all those points to a common terminal on the board, then run a wire from that terminal back to the ground at the supply capacitor. The capacitor on the Tone control can be wired directly to the Intensity pot, then a ground wire run from the two lugs of the Intensity pot to the common ground on the board.
The pots should be connected to a separate preamp ground, not to the power amp star ground with the filter caps. See the thread in my signature for more details.

Thanks,
Josh
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Re: Power transformer wire grouping help

Post by davemojo »

Bieworm wrote:
Wed 03/17/21 1:20 pm
"If" you solder to the pots directly there is something important to consider. The pot should be dialed to zero or to max. It's important the wiper is free from overheating because the carbon might be damaged and ruin your brand new pot.
Its just better practice not to solder to the pot housing. I've seen people solder a ground buss at the pots, but with legs to the grounding lugs of the pots, so the buss is like 1/2" in offset from the pots
I have set the pot volume to zero, it was written on the instructions.
I don't believe to have overheat the pot, hopefully.
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Re: Power transformer wire grouping help

Post by TriodeLuvr »

JMPGuitars wrote:
Wed 03/17/21 2:42 pm
TriodeLuvr wrote:
Wed 03/17/21 12:53 pm
If you decide to change it, you will need to remove all connections that are wired to the ground bus. You would need to instead connect all those points to a common terminal on the board, then run a wire from that terminal back to the ground at the supply capacitor. The capacitor on the Tone control can be wired directly to the Intensity pot, then a ground wire run from the two lugs of the Intensity pot to the common ground on the board.
The pots should be connected to a separate preamp ground, not to the power amp star ground with the filter caps. See the thread in my signature for more details.

Thanks,
Josh
Good catch! I said: "...then run a wire from that terminal back to the ground at the supply capacitor." I meant to say "the supply capacitor for the preamp." Had it in mind, but forgot to write it down. Thanks!
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Re: Power transformer wire grouping help

Post by davemojo »

So the Amp is going to be completed this week I got stuck on couple on capacitors and one resistor but I will get them tomorrow and took few day off since I have to record some music at our rehearsal place, nothing big just some hobby stuff.

I begun to play guitar in parallel to my organ play so I am exited to try to Amp assuming that all is going to work right off I am done with the build.

Unsure if I showed here the Combo cabinet photos, it is now completed, the next one will be perfect while doing it I realized a few mistakes on working with Tolex but you know this is my first one so... some imperfections are expected I bet :roll:
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