PHONIC 740 mixer-amplifier

Is it someone that have experience with this?
This is faulty,SMPS is burned,blown IGPT,FUSE.
Owner said that this had another service attempt but SMPS burned again immediately.
 

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Thanks,my plan is to test this smps with a scope ,but i haven't a differential probe.
Second option is to power the driver chip only,looking for the output waveform.If you will have a look in posted circuit diagram,driver's chip power supply is isolated .A transformer is used.Next to this,is a simple diode rectifier and a 5v regulator.
Sadly,circuit diagram haven't any waveform.
The last option is to change anything,driver chip, driver transistors rectifier bridge,sensing resistors.clamp diodes,everything...
That's why i asked help from a familiar person.
I'm sure that this isn't the first failed Phonic mixer out there.
 
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this is a resonant type (LLC) converter, so the series cap C922 (large blue film cap) is rather challenged in current and voltage (1u/400V). so check the actual value, as self healing is euphemism for self destructing.

maybe some-one has accidentally switched the voltage selector switch (120/240)
 
the main difference is the gate charge, almost double the Rohm device. Intrinsic igbt timing is comparable. So the littlefuse will need more gate drive power and as the input capacitance is larger, the 33 ohms gate resistors need to be changed to 18 ohms for a comparable non overlap delay. this is just theory, and the proper operation needs to be verified by an oscilloscope. so you need an isolation trasnsformer on amp the supply to operate the scope.
 
the main difference is the gate charge, almost double the Rohm device. Intrinsic igbt timing is comparable. So the littlefuse will need more gate drive power and as the input capacitance is larger, the 33 ohms gate resistors need to be changed to 18 ohms for a comparable non overlap delay. this is just theory, and the proper operation needs to be verified by an oscilloscope. so you need an isolation trasnsformer on amp the supply to operate the scope.
I have found a lot of small signal transistors shorted, i suppose the IR2153 is faulty too.
Small signal transistors aren't available,i think that is time i give it up...
I found that long time ago,it was a repair kit in the market. Not available any more.
Αlso seeing many reports of repeated smps burned.I guess a bad designed smps.
I don't like an expensive questionable repair at all.
https://www.diyaudio.com/community/threads/powerpod-740-blowing-fuses-at-powerup.109317/page-3
PS I have both,isolation transformer and scope but i don't know what like must be the expected waveform.
 
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