Voltage halved at terminals 7 and 9

wieders · 1579

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Offline wieders

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on: July 02, 2016, 09:08:02 AM
I've ran through the instructions on including the speedball.  All voltages check out except terminals 7 and 9 are coming in at about 55 v rather than the expected 100.  Plugging in the amp and putting some music through resulted in a lot of low frequency hum if I turned the volume up.

Has anyone encountered this issue that could lead me down the right path here?


Offline fullheadofnothing

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Reply #1 on: July 02, 2016, 09:24:39 AM
Can you please clarify: is the Speedball in or not? If the Speedball is in, did the Crack work properly before it was installed?

Voltages this far off are a clear indicator that your amplifier is not working. Do not attempt to use an amplifier that is not working; doing so may damage your headphones.

Joshua Harris

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Offline wieders

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Reply #2 on: July 02, 2016, 09:33:44 AM
The speedball is in.  The crack worked properly before I installed the speedball.


Offline fullheadofnothing

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Reply #3 on: July 02, 2016, 01:51:55 PM
Post pictures.

Joshua Harris

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Offline Paul Birkeland

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Reply #4 on: July 05, 2016, 09:03:42 AM
What voltage do you have at B+ on the big PC board?

I agree with Josh, photos will help.  Trying to use an amplifier that does not pass its voltage checks will not.

-PB

Paul "PB" Birkeland

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