I cannot check now but I think it was the same in both modes. Certainly relay did not click in both modes, and I am almost sure I measured in both modes and it was the same 25/30V at OUT. And I have no fuses in main amp boards atm.Is the mode switch in normal or class A? Put it in normal.And remeasure.
Oh yeah, the original output transistors were shorted. I replaced them with the popular today's drop in equivalents On 2*93/2*94 which are there at the moment, possibly shorted now too :/Did you find any shorted output transistors ? And are they still in circuit? Are the main amp fuses installed ?
The fuses are not installed.Did you find any shorted output transistors ? And are they still in circuit? Are the main amp fuses installed ?
I haven't replaced any original transistors except the output ones that are in circuit.TR604 and TR609 still in the circuit ? TR610 and TR611 as well ?
Need to be all checked in both channels.TR604 and TR609 still in the circuit ? TR610 and TR611 as well ?
All transistors checked in one channel and all tested good on Peak DCA55. I mean every single transistor including the new outputs on the main amp pcb for the left channel.Need to be all checked in both channels.
Definitely..Diodes?
You're just going to keep on blowing up more amps and outputs until you build yourself a DBT.And do you think I blew my new output transistors already?
Is it ok? I will do away with the switch I think. Do I have to care about polarization in terms of live and neutral as I saw in some other schematics if I don't know how it is in my wall socket anyway? The biggest bulb I managed to get is 60W due to laws in Europe. They sell them as decoration not lighting in such wattage, so I have it really cute in 1920's style.You're just going to keep on blowing up more amps and outputs until you build yourself a DBT.
Checked all diodes, most in circuit with multimeter, seemed ok, i.e. worked one way only. Just one had to be pulled out and tested ok.Definitely..
Yeah, good.2SA679 (PNP) MJ21193
2SC1079(NPN) MJ21194
I assume the mica insulators on the power transistors were in good condition.
Yeah, pic is perfect, and don't need to worry about live/neutral or switch.Is it ok? I will do away with the switch I think. Do I have to care about polarization in terms of live and neutral as I saw in some other schematics if I don't know how it is in my wall socket anyway? The biggest bulb I managed to get is 60W due to laws in Europe. They sell them as decoration not lighting in such wattage, so I have it really cute in 1920's style.
View attachment 957659
Have that DBT thing. I was messing around on main amp pcb and shorted 2 legs of a transistor with multimeter probe, the 60W bulb gave me heads up by illuminating high so kind of worked but I still blew out 1 nearby transistor and zener diode at that timeYeah, pic is perfect, and don't need to worry about live/neutral or switch.
I found some amps may not get a relay click with a 60W, but you can try turning the idle setting all the way down to help. You could maybe use multiple bulbs to increase the wattage if it won't click (on a working amp).
Just means you can do a safe test each time you change something, with the bulb tester it can't draw enough current to blow outputs, and even smaller parts will take longer to burn up.
It's 0.07V between these 2 spots (0.39V at R618/TR604 and 0.32V at TR608/TR609)FR601,2 checked?
Maybe VR602,3?
I'm inclined to think transistors, however all tested ok.
Maybe measure voltages at pins A,B,C,S on one side.
Also by measuring the voltage drop (mV) across R618 will point to the direction of increasing voltage/problem,
ie RED probe connected to R618/TR604 node, black probe connected to TR608,9(e) node.