Almost no output

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Lordhumongous
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Almost no output

Post by Lordhumongous » Sun Mar 03, 2019 5:51 pm

Hello all! Just finished up my metro spec 1987. Sourced all the parts from valvestorm except a transformer set from classictone. Let me begin by saying I am NOT an amp tech. I just want to rock. I can follow directions however and sought to build one of my dream amps I couldn't otherwise afford. That being said, after start up, amp has almost no volume. Does emit a sad volume while turned all the way up. Eq and presence controls all function properly as well as bright channel is bright, normal channel is darker as one would expect. Does this sound familiar? Hoping someone can counsel me through this. Thank you :rockon:

stryker59
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Re: Almost no output

Post by stryker59 » Sun Mar 10, 2019 1:29 pm

Check the 470 ohm resistor between the 1m pair at the phase inverter and make sure you didn't use 470k ohm

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neikeel
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Re: Almost no output

Post by neikeel » Tue Mar 12, 2019 8:14 am

Typical one is 470k cathode resistor on PI instead of 470R

Look and measure between the two 1M resistors on the board.
Neil

danman
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Re: Almost no output

Post by danman » Tue Mar 12, 2019 7:23 pm

Yep...Neikeel has the answer! Most likely a 470k between the two 1m resistors in the middle of the board instead of the correct 470 ohm. Happens quite a bit in new builds unless you measure every resistor before installing.

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neikeel
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Re: Almost no output

Post by neikeel » Sun Mar 17, 2019 12:39 pm

:what:
Neil

danman
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Re: Almost no output

Post by danman » Sun Mar 17, 2019 6:48 pm

He must have got it sorted out and playing right :rock:

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axeman
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Re: Almost no output

Post by axeman » Mon Mar 18, 2019 12:55 am

He probably crossed the the green wire for V1? Not sure have to see.

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