No input front or rear MP-1

[Mxzx]

Sorry haven't been around in a while!

I will get on that one of these days and report back.

Thanks for the help!

[MarshallJMP]

ok keep us updated.

[Mxzx]

Just sent you an email, i want to replace the front input jack with what was supposed to be there.  It was converted to front & rear input, but I don't need that.

I did notice when I plugged the unit in to an amp, everything inside seems microphonic.  When you tap on anything in there, you can hear it through the amp.  Don't know if this gives any clues or not.

Thanks

[MarshallJMP]

Mmm seems to be quite good,can you take a pic of the input jack and the pcb around it?

[Mxzx]

Sure, here ya go!

[MarshallJMP]

Ok i see now,it's connected the wrong way.The blue wire has to be connected to the second hole.So desolder it and solder it to the hole next to it.The jump wire is ok.It doesn't work because it's not connected to the input.
Maybe also clean up that bridgewire,get the white wire out and put in a small bridge wire like on the pic,this will lower the noise a bit.

[Mxzx]

I'll get on it tonight!

Thanks!!

Hope the fix will be that easy!

[MarshallJMP]

Ok keep us updated

[Mxzx]

Ok, I'm a little confused.

My blue wire appears to be going the same place as your red wire, 2nd terminal to left of 2 resistors. Is that wrong?

What is the proper connection of the rear input to front?  Blue tip to blue tip, white to white, ground to ground?

Is this right now?

Thanks

[rnolan]

Hey Mxzx, from looking at the pics (hey MJMP correct me if I'm wrong), your blue wire needs to be the same as MJMP's red wire (i.e. tip (+ve) of input jack) and your white wire, the same as MJMP's black wire (i.e. shield (-ve) earth), so plug a guitar lead in and check continuity. As +ve goes to the terminal that MJMP's red wire is in, and -ve is combined with the shielding into the terminal that MJMP's black wire is in (so sleeve on guitar lead, your white wire).
Then there's the bridging wire.. ok from MJMP's pic it should only be between 2 (horizontal) terminals, but in your pic it also bridges with the +ve input (blue??, red). So check the other side of the PCB to see maybe why? Now, if a trace has burnt out on the other side of the PCB between those 2 terminals, then ok leave it as is, otherwise why is it bridged there ???? (and may be your problem ??)

[MarshallJMP]

Like R says you need to remove the bridge wire going from the blue wire to the hole next to it.The rest looks good.

[Mxzx]

Ok thanks, I'll remove that jumper.

I'm still not sure on the connection between the two input jacks.  When I wire them in parallel, blue/blue, white/white, I get continuity between the blue and white at board with no input jack plugged in at either end, is that right?

I bought this amp with this mod started, no idea who's mod it is.  I looked at the mod on this website, and it looks like there is other stuff that needs to be done.  Are there any other things that I need to be looking for here?  I can take pics of anything you might need to see.

Thanks,
Michael

[MarshallJMP]

With nothing connected you should get continuity between the blue and white.This is because when nothing is plugged in the input is grounded,else the input would float and it becomes an antenna which would pickup a lot of noise.

Can you take pics of the rest?

[Mxzx]

Thanks!

Yes I will get some pics up in an hour or so.

[Mxzx]

Here ya go.

Thanks!