Marshall MG101fx

[muser]

I'd love to have the Marshall mg101fx schematic ! Thankyou !
(and no, the mg100dfx scheme is not the same )

[muser]

No one ?

No one ?

[Enzo]

On the support site, the schematic has a big old red notice in the middle exclaiming written permission needed to make copies. My service dealer agreement precludes sharing that drawing.


I can however answer questions about it. WHat problem are you trying to solve?

[balaboo]

Enzo, I have a MG100HFX that has a dead power amplifier - the headphone jack works, and I can get a click from the speaker when I touch the base of the MJ15032/MJ15033 driver transistors. However, the board is filled with mostly SMT components, and I had no luck trying to use the MG100CDR schematic. Any suggestions ? The power supply measures +-43V, and the output transistors 2SC5200/2SA1943 appear to be okay.

Thank you;
Balaboo

[Enzo]

Hi Balaboo

Let's not confuse Muser's MG101fx thread with an MG100 HFX. GO to the maintenance and repair section and start a new thread for your amp.

In the meantime try a cord from FX return to FX send.

[balaboo]

Fixed !!
In desperation, I started probing around the SMTs with my DMM; lo and behold, there were TWO transistors that had not been properly soldered. I used 0.022 silver solder and now the amplifer plays perfectly.

Thanks for your help.