Just been giving this amp a go at seeing if I can repair it as I can not find 1 place worldwide that'll attempt it.........
So, problem is, powers up fine, no speakers connected, nothing else, shuts down a few minutes or seconds later. Thing is, when it shuts down, then a power on attempt causes a shut down straight away, leave it for 30 seconds odd and it comes back on.
Funny enough, no cold solder joints, PSU fine, transistors fine, but on discharging caps on the power board got 1 cap 38% down on Vloss, 5 others at 8% - 18% loss, so, is that more or less telling me, replace them? Is it a loss less, or on 3% ok?
The main Gold Tune caps, 27000uf 71v are down to19000uf and the other 17000 odd uf tiny bit of volt loss also...
So, problem is, powers up fine, no speakers connected, nothing else, shuts down a few minutes or seconds later. Thing is, when it shuts down, then a power on attempt causes a shut down straight away, leave it for 30 seconds odd and it comes back on.
Funny enough, no cold solder joints, PSU fine, transistors fine, but on discharging caps on the power board got 1 cap 38% down on Vloss, 5 others at 8% - 18% loss, so, is that more or less telling me, replace them? Is it a loss less, or on 3% ok?
The main Gold Tune caps, 27000uf 71v are down to19000uf and the other 17000 odd uf tiny bit of volt loss also...
Its likely you either have a capacitor going S/C when power is applied or a main feed resistor overheats or breaks down under current load.
I always check the resistance of power components by using a low current digital multimeter on ohms to measure resistance between a soldered joint and a leg of the component.
Why didn't you measure power supply voltages under fault conditions to narrow it down ?
I always check the resistance of power components by using a low current digital multimeter on ohms to measure resistance between a soldered joint and a leg of the component.
Why didn't you measure power supply voltages under fault conditions to narrow it down ?