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Hoffman Amps Forum image Author Topic: MANLEY dual mono block microphone preamp won't power up  (Read 1908 times)

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Offline Jonas

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MANLEY dual mono block microphone preamp won't power up
« on: February 02, 2023, 12:30:39 pm »
Hi, I'm not sure I posted this to the correct place but I hope so!!

I have a MANLEY dual mono block preamp on the bench that will not power up.  I have no schematic (more than likely will not be able to get one). I have not tried to power it up yet. I plan to do a thorough inspection to look for the obvious; burnt components, leaky caps, broken wires, bad solder joints, etc.  I can get high res pics as well....

Below is intel from the owner

1) installed in a rack with other equipment but not frequently used, but power is typically left on.
2) tubes checked out OK (qty 2 - 12AX7 and qty 2 - 12BH7A / one per channel)
3) 1 AMP slow blow instantly blows when turned on


Any suggestions on how to proceed?

Offline sluckey

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Re: MANLEY dual mono block microphone preamp won't power up
« Reply #1 on: February 02, 2023, 01:04:36 pm »
Build and use a current limiter light bulb.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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