Digital Designs Z2HV

Going back through this amp to find the faults .

When looking the amp over I found this in the windings of 1 of the transformers .
Wondering will this cause any issues ?
Also wondering should I reflow them solder where the windings go through the board ?
 

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Going back through this amp and noticed something . The diodes that connect to the drain leg of the power supply fets and to the 4148 diodes .

I have 36 volt zener diodes in there 1N4754 .
The schematic shows them as 39 volts .

Should I switch them out to what the schematic shows ?

some of the locations these are in
D31B,28B,31B
 
Back to this amp . I don’t get it .

the power supply will power up and idle fine . If I put the rectifiers back in the amp it will draw excessive current . I swapped out the rectifiers with know good ones and made sure they were in the right locations still no change with them in circuit the power supply board will draw excessive current
 
The outputs are not in the amp I have the 2 boards separate right now . I’m working on the power supply board only .

The rectifiers im using are FMG36S/FMG36R

I tried installing them 1 at a time amp draws excessive current as soon as 1 is installed .

I tried a FMG36S in D19’s location amp will draw current took it back out and tried the FMG36R is F19’s location amp will still draw excessive current .
 
Try this... The amp needs to be completely isolated, no connection to ANYTHING.

Connect your 12v power supply (with limiting resistor in series with it), across the positive rail caps. Be sure to get the polarity right. Do the positive rail caps charge to the 12v supply voltage?

Do the same with the negative rail caps (again, get the polarity right). Do they charge to the 12v supply voltage?
 
Ok I repaired the board and got it to power up and idle fine put the 2 boards back together amp powers up and idles fine.

Amp is producing all the regulated voltages and both rail voltages . The outputs have rail to rail oscillation and the relays engage.

Amp has no audio .

Any ideas ?