I need cross reference for this transistor HUF75339G3 or a good replacement for it .
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The IRFP064N is generally a good substitute. Seankane has probably repaired more of these than I have. Maybe he can tell you what works definitively.
The clamp has been heated to a point to where it's probably lost its temper. It will have to be straightened if you can't find a replacement but won't be as strong as it was. Install it on the regulators or something that doesn't dissipate a lot of heat.
The clamp has been heated to a point to where it's probably lost its temper. It will have to be straightened if you can't find a replacement but won't be as strong as it was. Install it on the regulators or something that doesn't dissipate a lot of heat.
Thanks for the quick reply Perry. I will wait to see what Seankane says before I make a orderthem. for the clamp I heated it up and bent it back in to shape and re tempered it I hope that does the trick.
No but you need to check them after removing all of the power supply FETs.
If the insulators that the FETs are soldered to are delaminating, you'll need to either replace them or use something for an insulator.
If the insulators that the FETs are soldered to are delaminating, you'll need to either replace them or use something for an insulator.
the insulators is ugly but good and all resistors are good at 10 ohm's but the one from the fried fet at 136 ohm not good.
An externally hosted image should be here but it was not working when we last tested it.
I have never had on of these in for a power supply. It's always been little things like op-amps and such. I wouldn't be afraid to run IRFP064N FET's in this amp with either 10 ohm or 47 ohm gates.
I have used this FET as a sub in many Rockford amps with great success.
Make sure you change the drivers as well regardless if they test good. Cheap insurance.
Do you have any shorted outputs?
I have used this FET as a sub in many Rockford amps with great success.
Make sure you change the drivers as well regardless if they test good. Cheap insurance.
Do you have any shorted outputs?
Thanks for your feedback that's good to know that they will work I already ordered them and new 10 ohm @ 1% resistors now for the outputs have not even looked at them yet I need to.
No not yet I am going to do that on Monday should I use something different from the MPSA06 & MPSA56 ?
The way seankane ask his question that why I asked and for having a scope no 🙁 I need to get one I have not used one since 1989 😱 My main focus was installations for many years I had decent luck with basic repair and I know when I'm over my head and to send it to someone smarter then me to fix it.
Perry or seankane do either of you know what the positive / negative rail voltage runs at? The schematic does not say. By the way I went with 47ohm gate resistor with the IRFP064N FET's. Mouser sent me me the wrong size resistor a 1 watt instead of the 1/4w I ordered 
nice
niceThere's no positive/negative rail voltage. The amp has a single rail and it's driven positive or negative as needed. You have to measure across the caps or the rectifiers with a meter to measure the rail voltage.
The actual rail voltage isn't regulated.
I would expect 80-90v across the rail caps.
The actual rail voltage isn't regulated.
I would expect 80-90v across the rail caps.
Well all parts are replaced and it powers up but go straight into protection since I don't have a scope I can't go any further so I'm going to send out to finish the repair. Thanks for your guy's help.
update replaced U21 it came out of protection plays fine. Thanks again for your guy's help.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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