Marshall 5275 (75 Reverb) Power Switch Replacement

[@Mruppertrinity]

Thanks for this. I have just purchased a new switch for my JCM800 combo and was stumped by the fact that the new unit only had 4 terminals.

[@markdupriest1854]

Looks like you have replaced the axiel caps. Did you replace the bjt transistor on the heat sink? And if so what was the replacements?

[@RedFez]

I hadn't knowingly replaced any or had any replaced, but it has been serviced a number of times and I bought it second hand, so I'm not surprised if caps had been replaced. Although, as I type, I have just replaced ALL the caps as the amp was not working. Its now back up and running and sounds better than ever!

[@markdupriest1854]

@@RedFez on the heat sink you should have a MJ 2501 and a MJ 3001... What one is close to the transformer. I bought a Amp like yours and I'm trying to get it up and run. But someone put the wrong bjt transistors in it... Help... I'd appreciate it... Thx

[@antonioandriani]

Hi, do you know if this amp is mosfet one? Thanks in advance. Regards, antonio

[@RedFez]

From what I can tell, no, it is not Mosfet, but I could be wrong

[@markdupriest1854]

On the output transistors... What order do they sit from the transformer. Mj 2501 then Mj 3001. Or Mj 3001 then Mj2501?

[@ericrose5632]

DO you know of U.S. supplier of these switches? The one I saw, had no lamp in it. Or is there a UK supplier...? I assume the Marshall company would sell direct to a single human...?

[@CathodeULT]

I just wanted to replace the bulb in my switch. Didn't realize it was this involved. Hell with it, I'm ok with a dark switch.

[@lost2gether1]

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