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Hoffman Amps Forum image Author Topic: Add Princeton micro power circuit to princeton reverb  (Read 1716 times)

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Offline dsones

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Add Princeton micro power circuit to princeton reverb
« on: September 27, 2024, 08:02:33 pm »
I'm working on modifying a fender princeton reverb amp to use Rob Robinette's princeton micro power circuit. The goal is to have the reverb with the 1 watt power output. I can't find a classictone 40-18027 power transformer so I will use a hammond 270CAX 500v CT 81ma 6.3V@2.5A HV center tap 5V@2A. This is the closet power transformer to the classictone I could find. Not sure what output transfomer to use. The output transformer in the princeton reverb is 15w 8.5k. The micro amp uses a 22.5k 8ohm output transformer. I think I can use the reverb transformer that is in the princeton reverb. I added presence mod and mid/raw mod. I removed the tremelo circuit. Used the princeton reverb wiring for most of the circuit and the princeton micro power circuit. I'm a little fuzzy on where to connect the reverb transformer red wire in the micro circuit. I've attached a pdf and png of my wiring diagram. The diagram is close as I could get with the software I used. If you zoom in you can see the details. Any suggestions or corrections would be greatly appreciated.
Thanks

Offline roarshock

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Re: Add Princeton micro power circuit to princeton reverb
« Reply #1 on: September 27, 2024, 09:30:33 pm »
Cool idea! Post a schematic for best results. :icon_biggrin:

Offline Latole

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Re: Add Princeton micro power circuit to princeton reverb
« Reply #2 on: September 28, 2024, 03:25:18 am »
Cool idea! Post a schematic for best results. :icon_biggrin:

Right ; Schematic will help more.

 


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