Author Topic: Wolfshirt - cutting out/dropping volume  (Read 795 times)

the3secondrule

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Wolfshirt - cutting out/dropping volume
« on: October 01, 2014, 02:54:03 AM »
this is a weird one.
I've built up a wolfshirt this evening. fired up first time, was playing for a few minutes and it started gating / sputtering and cutting out. within maybe a minute, the volume completely died. Unplugged for a few minutes, came back, tried again, and then same thing happened, almost immediately.

voltages:
Q   C     B     E
1   5.1   0.5  0
2   4.5   5.2  4.5
3   7      0.8  0.1
4   7.5   0.8  0

anything standing out?
Q2 looks wrong to me.
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mgwhit

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Re: Wolfshirt - cutting out/dropping volume
« Reply #1 on: October 01, 2014, 07:35:08 AM »
You shouldn't have 0V on any of your emitters.  Check for continuity to ground from those pins.  If there is no short, try subbing the transistors.

Bret608

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Re: Wolfshirt - cutting out/dropping volume
« Reply #2 on: October 01, 2014, 08:18:27 AM »
Let me know if you need voltages from a working unit if you still don't have it sorted after checking as Matt describes.

the3secondrule

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Re: Wolfshirt - cutting out/dropping volume
« Reply #3 on: October 01, 2014, 11:45:04 AM »
You shouldn't have 0V on any of your emitters.  Check for continuity to ground from those pins.  If there is no short, try subbing the transistors.

I've checked and I don't have continuity to ground from any of the emitters.
I've replaced Q1+2 with the same result. Now I can't get it passing any signal at all.
I'm off to work soon, but fire any ideas at me and I'll check when I get home

Transistors are pn3565, and I've double/triple checked the pinout
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mgwhit

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Re: Wolfshirt - cutting out/dropping volume
« Reply #4 on: October 01, 2014, 12:30:59 PM »
If you can upload some clear photos of both sides of the board, it will be easier to try to debug this.

selfdestroyer

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Re: Wolfshirt - cutting out/dropping volume
« Reply #5 on: October 02, 2014, 01:07:57 PM »
I had a similar issue with another build. It would play fine for 2 or 3 minutes then it would crap out. I replaced the electrostatics and all was well. I think I had a bad batch of 10uFs at one point. Just a thought.

Cody

the3secondrule

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Re: Wolfshirt - cutting out/dropping volume
« Reply #6 on: October 02, 2014, 01:10:16 PM »
I had a similar issue with another build. It would play fine for 2 or 3 minutes then it would crap out. I replaced the electrostatics and all was well. I think I had a bad batch of 10uFs at one point. Just a thought.

Cody

That had crossed my mind as well... Pretty sure my 10u electros are from Tayda too.
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