Final Voltage Check Failure - Negative terminal 1

Sdocherty · 897

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Offline Sdocherty

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on: February 03, 2023, 03:06:35 PM
Hi,

I recently completed the crack kit, and all of the resistance checks looks good according to the numbers stated in the guide.

When I first powered up the amp to do the final voltage check, I did not realize that the 12/13U cap was backwards.  Some smoke came out, and I replaced all three of the 220uf caps with new ones.

Now the voltage at terminal 1 reads -1.29VDC, where it starts at ~0.08VDC prior to connecting the power cord. None of the other terminals from 1-10 give the correct voltage.  I also noticed that the LEDs around the 9 pin do no illuminate.

I went through the circuit and double checked all the solder connections, and measured the resistance a long the ground path as described in the stickied post and all points appeared to be in spec.

Any advice on how to fix the issue would be appreciated.



Offline Paul Birkeland

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Reply #1 on: February 04, 2023, 05:59:43 AM
Can you repost your image, as it did not come through?

Getting a look at your build would indeed be very helpful. The LEDs will not illuminate if the voltages on terminals 1-5 are near zero.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man