Kaption DZ-300.1 help

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I found different resistances on the output fets even know they are the same so I took them out and checked them and they seem to be ok I think. I get OL on every configuration except from pin 3-2 at 0.48v. So I put them back in and powered up the amp. It didn't go into protect so I tried playing it and there was no sound. I then took the two power fets out and checked them and I'm suspecting leaky gates but I'm not sure. When I check in diode mode everything seems fine but when I check in resistance from pin 3-2 one goes to 13.7m ohms and started to climb slowly 0.01m ohm at a time and the other one started around 14m ohms and climbed slowly too by 0.01m ohm. Then I checked again and one read 13.68m ohms and the other goes to 14.05m ohms and stayed there. Then I checked again and they both were over 14m ohms and they slowly started to climb 0.01m ohm at a time to around 14.35m ohms.

These seem like weird readings but I'm not familiar with leaky fets. They are DFP50N06 fets.

Thank you in advance
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I just powered up the amp to check voltages at the Fet legs, her is what I got.

Power fets are the same:

Pin 1: 4.45v
Pin 2: 12.25v
Pin 3: 0.00v

Output fets are labeled the same:

Pin 1: -0.165v
Pin 2: 41.5v
Pin 3: -0.18v

Pin 1: -41.4v
Pin 2: -0.18v
Pin 3: -41.5v

Do these readings seem ok?

I checked the speaker terminals and they have -.163v in positive terminals and -0.003 v in negative terminals. The rca's have a little voltage on the inside and outside.

I appreciate any help you could give me.
Here are the pics. Hopefully they are ok.


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Here is the pic, I'll start checking what I can in that area. I checked the Zener diodes and I can get resistance measurements in both directions, do I have to take them out of the board to check them properly? Is it worth checking into or do you think the problem is something else? Thanks for your help.


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I think there was something on D56 that made it appear weird looking during the picture. it seems ok and after testing I don't think it's shorted.

Here are the voltages of the IRS2092.

Pin 1: 4.94v
Pin 2: -0.003v
Pin 3: -0.164v
Pin 4: 4.62v
Pin 5: 2.418v
Pin 6: -4.95v
Pin 7: -36.4v
Pin 8: -38.36v
Pin 9: -30.99v
Pin 10: -41.4v
Pin 11: -41.4v
Pin 12: -26.67v
Pin 13: -0.182v
Pin 14: -0.167v
Pin 15: -0.138v
Pin 16: -0.178v
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That would tend to confirm that the IC has failed.

The only reference that I have is the datasheet and the reference circuit. Legs 1 and 3 of one of the output transistors should be connected to pins 10 and 11 of the driver IC.

What is the resistance between pin 11 and leg 1 of Q131?

What is the resistance between pin 10 and leg 3 of Q131?
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