# Repairing Memphis st3004



## RollinSingle (Jul 30, 2012)

I have never repaired electronics before, but I know enough to get into trouble. I'm pretty sure I lost output transistors on one channel. Using the diode setting on my Fluke, 3 pairs of transistors read the same and one pair is different. The transistors are irf540. I am looking at IRF540PBF, IRF540NPBF, or IRF540ZPBF from digikey. Any thoughts on which would be a good fit?
Thanks!


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## outerlimits (Jul 2, 2009)

I did the same a few months back. I ended up replacing them with "IRF540PBF". I replaced all of them on all four channels. Try to get a matched lot of transistors.

Here a link to where I got help fixing my amp.
Memphis 16-ST3004 - diyAudio

Good luck

Jake


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## RollinSingle (Jul 30, 2012)

Thank you for the help.


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## RollinSingle (Jul 30, 2012)

I replaced all 8 of the output transistors with IRF540PBF, cleaned off the old thermal compound and applied new. Amp powered up without going into fault and all 4 of the channels sound great. I successfully fixed the amp, thanks for help!


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## outerlimits (Jul 2, 2009)

Glad it all worked out!

Nice job
Jake


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