Crikey, I had no intention of starting an on-line fisticuffs!
Let's just rewind a moment:
As I stated, the schematic that I posted is NOT correct to the PCB layout that I have.
The amplifier has not been modified or opened prior to my acquisition.
There are two windings that are energised by 240V- one at switch on and the other after a delay. There is no provision for a 110V input except by a different transformer on manufacture. The back panel clearly states '240V'.
I understand the thermistor in the schematic but this relies on both windings being energised, albeit gradually, at switch on but my version does not have this.
Now:
Arthur- your schematic is very close to what I have, although my relay contacts are actually between the fuse and the transformer rather than the PCB edge and the fuse, but the same thing in effect.
Thanks for the link to the service manual- I had not managed to find this. I have not downloaded it yet as two browsers have given an error, but I will try later.
Chris- I have the transformer removed from the amp, and I am most certain that the winding is shorted/damaged. When I return from work I will power it up on the good winding and measure the secondaries, then attack it with a scalpel etc.
As I see it- one winding will supply the stated secondary outputs but at only half the rated VA, so should be OK to determine the secondaries to specify a replacement if I need to.
I think everyone has become a bit fixated and confused that there is an option for 110VAC supply, which I am sure is not the case. On opening the amp there was a fuse fitted in both F101 and F102 positions. The F101 fuse had failed catastrophically with the link sputtered on the glass.
If, as has been suggested here- for some supply condition- F101 was not fitted, then the amp would not work as the relay would be open and the transformer isolated so unable to power the relay circuit to energise it.
Just to note- I think that the '250' legend by some of the connections to the PCB refers to 1/4" AMP tag type terminals rather than a voltage.
I will report back later. Thanks for the suggestions and interest.
Regards, BT