Marshall MG100DFX problem...?

[acorkos]

This amp was blowing fuses....i tracked down a bad TDA7293 output transistor. I replaced it...fuse holds and everything works. But when I hit the guitar strings hard at higher volume settings, the guitar sound cuts out and I can hear a high pitch static squeal along with the intermittent guitar signal.

Is there another component in the circuit that gets damaged when an output chip shorts? I'm not sure where to look. Thanks for your help.

[acorkos]

...anyone...?

[Enzo]

Other parts could be damaged, usually not though. Al I can seay is get out the scope and start looking for what hte trouble signal looks like and track down where it comes from.

[badsun79]

help!!!!!!!!!

my mg 100 hdfx cuts out sometimes off then on does it other times a slap other times it comes back when it's ready help me please

[Enzo]

Check the solder under all the jacks and controls. Check the cutout contact in the loop jacks by plugging a spare cord into the effects send jack and the other end right back into the effects return.

[nyge23]

i think i might have the same problem

i am an apprentice electronics engineer with the same amp that is blowing the 1.6A internal fuse.

is that the same fuse that yours is blowing?

and did you ever fix the problem?

i am pretty sure i can fix this, your help will will very greatfully recieved.

also if i fix this i will tell you how i did it

[pig-killer@hotmail.com]

i think i might have the same problem

Marshall MG100DFX keeps blowing 1.6amp fuse. Why?

[Jazz P Bass]

Because something in the amp is shorted & you keep putting a new fuse in.
Disconnect the multiconductor cable that goes to the output IC.
If another fuse holds, the IC is bad.