OT noise - need some help

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neikeel
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Re: OT noise - need some help

Post by neikeel » Fri Apr 13, 2012 6:40 pm

Without wishing to be rude but your lead dress could be better as you have some long loopy wires, with wires crossing at all sorts of angles. Also wrapping a wire around another wire is not the same as twisting the two together to get hum rejection. They have to be twisted evenly together so they cross each other at 90 degrees. Same with all the other wires in the amp. If they touch or cross in close proximity they should do that at 90 degrees or you are going to get noise interference, PO, hum etc, at least in an amp where you are going for a high gin sound.

BTW what are your values of your dropping resistors, my tired eyes make two of them 15k and another 8k2 - but may be the 15k are 10k (black is looking green :roll: )
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vanhalen5150
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Re: OT noise - need some help

Post by vanhalen5150 » Sat Apr 14, 2012 6:37 am

Yeah, I've had to move a lot of things around diagnosing the initial problem I had with the rectifier, dual power selector. The other thing is where some of the turrets are on the board. They really do not line up well with the preamp tubes on the chassis. The dropping resistors are 8.2 and 10. I left extra length on a lot of wires in case i had to lift the board. I figured I'd go back and clean up the wire once I got the thing working. Not yet.
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Re: OT noise - need some help

Post by vanhalen5150 » Wed Apr 18, 2012 11:29 am

ValveStorm wrote:Yup...post some closeups of the Larmar...
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Re: OT noise - need some help

Post by vanhalen5150 » Wed Apr 18, 2012 11:30 am

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vanhalen5150
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Re: OT noise - need some help

Post by vanhalen5150 » Wed Apr 18, 2012 11:33 am

The noise I hear totally decreases when the Larmar is counterclockwise. It increases gradually as the Larmar goes clockwise. Im pretty sure( :lol: ) I have it in correct. I went by Georges schem from the wiki section. I'm 100% correct 60% of the time.
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YMI5150?
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Re: OT noise - need some help

Post by YMI5150? » Wed Apr 18, 2012 11:41 am

I'd take it out and see how the amp runs. not what you want to hear but that's what I'd do...

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Re: OT noise - need some help

Post by vanhalen5150 » Wed Apr 18, 2012 12:13 pm

I'll check the inputs/outputs and OT. If they check out then i'll remove it. There is one place on the pot where it looks as though there is no solder but thats just some excess wire I wrapped around the lug. Its been removed since. I have to stop starting so many projects at once. This amp looks like shit.
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