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Hoffman Amps Forum image Author Topic: Another Pro Junior Kit Question  (Read 1688 times)

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Offline ListerHayes

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Another Pro Junior Kit Question
« on: January 29, 2020, 09:29:07 pm »
I'm having a new bug in my build.  I fired her up today and nothing.  I went through the checklist and everything still looks good.  I have a tiny amount of volume, but it cuts out when the volume knob maxes out.  The only thing I can see is the voltage drop on V4 at Pin 7 is around 340mv.  V3 is spot on at just under 3v.

Any ideas?
« Last Edit: January 30, 2020, 02:32:30 pm by ListerHayes »

Offline sluckey

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Re: Another Pro Junior Kit Question
« Reply #1 on: January 29, 2020, 10:45:21 pm »
Time to post some pics of your handiwork.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline d95err

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Re: Another Pro Junior Kit Question
« Reply #2 on: January 30, 2020, 01:33:06 am »
...and a schematic and preferably full voltage readings on all the tubes.

Offline ListerHayes

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Re: Another Pro Junior Kit Question
« Reply #3 on: January 30, 2020, 07:05:45 am »
Gotcha, thanks.  I'll get the details and pics up when I get home from work.

 


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