Still having strange voltages on Speedball boards after installing film caps

jeffreyperr · 1177

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Offline jeffreyperr

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So since I couldn't find any problems with any bad connections I decided to unsolder the Speedball boards and replace the wires, I even went as far as reinstalling the old electrolytic capacitors. So when I got the point of testing the voltages on the small board(Still haven't put the large one back in) I still got incorrect voltages. All the LEDs on the small board light up.

I did notice something I didn't see before and that's that one of the LEDs on the smaller tube socket was not lit and I checked the voltage on its lead and it was still receiving power just like the lit one. I'm not sure if this caused the problem or is a result of the problem. I really want my amp back :(. Below are the voltages I measured on the small Speedball board.

Small Speedball board...
0A:Fluxuates between 190V and 0V
1A:0V
A/B:175.1V
1B:0V
0B:0\Fluxuates between 190V and 0VV

The correct voltages would be...
0A:60-90V
1A:170-270V
A/B:0V
1B:170-270V
0B:60-90V



Offline Paul Birkeland

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B-A/B is supposed to be grounded, but you have 175V there.  Is the wire connecting to B-A/B going to terminal 3?  If so, how is the solder joint where the black wires meet at the headphone jack?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man