[camarada78]

Hi, 

I have a MP573 on my bench (version 1.3). It worked good for years and now it powers up but doesnt have sound.

Voltages are correct as per the setup and assembly instructions.
No shorts.

I notice the Relay was acting weird and somewhat faulty and ordered a new one (not installed yet). Resistance on the coil is varying a lot.

Meanwhile I injected a signal into the pin 7 of the input transformer and get sound normally, but if i inject into pin 2 I get no sound. 

Resistances on the transformer (installed):
2-4: 24 ohms
3-5: 22 MEG (definetely weird)
7-9: 126 ohms
8-10: 127 ohms


Resistances on the transformer (not installed):
2-4: 24 ohms
3-5: open (dead for sure)
7-9: 136 ohms
8-10: 137 ohms

I think this transformer is cooked. Is there another way to be 100% sure?

[JPK]

I think this transformer is cooked. Is there another way to be 100% sure?
If you have measured with the transformer completely disconnected, then it is already 100% sure.

One connection in the transformer is open. You could try to lift up the small PCB with the pins and check if you can see the disconnected wire.
If the wire is cut elsewhere, then you will have to replace the transformer.