Deluxe reverb build, troubleshooting

Discussion in 'Amp Tech Center' started by Huanderson, Aug 17, 2019.

  1. Huanderson

    Huanderson TDPRI Member Double Platinum Supporter

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    Hey all,

    I recently finished a deluxe reverb build ,

    I plugged in with light bulb current limiter and light bulb was dim in standby , but went full bright out of standby..

    When switching out of standby there is a loud hum and crackling that resides after about 10 seconds. Everything functions; reverb, tremelo, treble, bass, and volume. Signal is weak and distorted though.

    I tried amp without current limiter and it smoked the 470ohm resistor on the bias circuit board ,

    Not sure what went wrong , here are some pictures , thanks 20190817_200400.jpg 20190817_081920.jpg 20190817_082057.jpg
     
  2. Nickfl

    Nickfl Tele-Afflicted

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    Bright light on your limiter = a short = don't take it off the limiter

    ... as you learned when you burnt up that resistor.

    You've got a short somewhere, maybe in the vicinity of the bias supply, though it seems strange that it would only indicate a short when you took it out of standby if the short was there. Unplug it, drain the caps and start testing for continuity to ground in the power supply where there should be none.
     
    zook and Paul-T like this.
  3. Huanderson

    Huanderson TDPRI Member Double Platinum Supporter

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    I found the culprit , i didnt clip the leads under the bias board, was direct shirt across the diode , amp works good now. The 470 resistor i roached still reads 445 ohms but i ordered a new one.
     
  4. Phrygian77

    Phrygian77 Tele-Afflicted

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    I did the same thing in one of my Princeton Reverb builds.

    I recommend that you use 3 watt resistor there. I also always use a 100uF/100VDC cap. It won't affect the tone. It's kind of a pain to replace components on the bias board, so I usually just pull the board up.
     
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