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Hoffman Amps Forum image Author Topic: Fender champ 12 Effectrode mod  (Read 2564 times)

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Offline Kesi from Hungary

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Fender champ 12 Effectrode mod
« on: May 29, 2022, 01:27:38 pm »
Hello, does anyone have experience with the Effectrode mod on a Fender champ 12. I'm working on the mod and finished the first part of the gain channel.  Now the clean part.  In the diagram of Effectrode a new/extra 220K resistor is drawn with a line just above resistor R21.  I don't know where to put it.  Instead of jumper W 5?  Or something else?  I'll try to post a picture and schematic.https://el34world.com/Forum/Themes/default/images/post/xx.gif

Offline PRR

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Re: Fender champ 12 Effectrode mod
« Reply #1 on: May 29, 2022, 01:44:44 pm »
.

Offline Kesi from Hungary

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Re: Fender champ 12 Effectrode mod
« Reply #2 on: May 29, 2022, 01:51:50 pm »
very fast answer.

You mean parallel? Thats makes it 440k.

Offline sluckey

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Re: Fender champ 12 Effectrode mod
« Reply #3 on: May 29, 2022, 02:09:47 pm »
very fast answer.

You mean parallel? Thats makes it 440k.
No. Replace R21 with a jumper wire. Replace R16 (47K) with a 220K. You could just use the removed 220K rather than using a new one, that is if you don't booger up the original 220K.
« Last Edit: May 29, 2022, 02:12:06 pm by sluckey »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Kesi from Hungary

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Re: Fender champ 12 Effectrode mod
« Reply #4 on: May 29, 2022, 11:14:38 pm »
Thanks for solving the problem.  This week the last parts will arrive and then I can finish the project.  Regards Kesi

 


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