Ashdown MAG300 oscillation

[glebert]

Z1 zener voltage correct?

Nope, it appears shorted.

[J M Fahey]

I'll add this schematic as it has a few bits not shown on the other.

NO short protection?
On a Stage use Musical Instrument amp?

Makes me think of:



Ashdown often despised it ... on Lateral Mosfet amps, which are PTC; but on Bipolars !!!!!

[glebert]

NO short protection?
On a Stage use Musical Instrument amp?

FWIW, my amp has a fuse on the speaker jacks that is not shown on the schematic.

[Helmholtz]

Nope, it appears shorted.

And don't forget to also check C10.

[J M Fahey]

FWIW, my amp has a fuse on the speaker jacks that is not shown on the schematic.

Well, that´s something.