All power supply fets are shorted from legs 1 to 2 in this amp..
On the outputs 1 of the high side fets and 1 of the low side fets are shorted across all 3 legs..
Since only 1 high side fet and 1 low side fet is shorted can I pull the rest of them
Out of the board and test them and use 5 of them for the low or high side and just order 5 of them or should I replace all 10 of them ?
On the outputs 1 of the high side fets and 1 of the low side fets are shorted across all 3 legs..
Since only 1 high side fet and 1 low side fet is shorted can I pull the rest of them
Out of the board and test them and use 5 of them for the low or high side and just order 5 of them or should I replace all 10 of them ?
If this is a clone with the fan between the driver board and the outputs, I tried this and had a VERY high failure rate. Virtually all failed during burn-in. Too much risk for $8 worth of readily available parts.
I have lots of FETs from these kind of amps.Sometimes am tempted to used them when my
stock run out. What about those from the amps like the hifonics when one FET fail from each bank ?
stock run out. What about those from the amps like the hifonics when one FET fail from each bank ?
I have this exact amp as well and it too is also under repair. Is there any way I can ask you to take pics of the FETS. Mine was refurbished before several years ago and I have a feeling that one of the FETS shouldn't be there. There is a single FB42N20D between the rest which are FB31N20D 's. But to answer, I recommend replacing them all at once. Like Ian said, it's cheap. Plus it'll save you a ton of headache since the others would likely blow shortly after reinstalling if you don't change them all.
All of the power supply fets are IRFZ46N
All of the outputs are FB31N20D
The 42n40 part is not correct ..
All of the outputs are FB31N20D
The 42n40 part is not correct ..
Anyone have any suggestions on this amp ?
Is there any upgrade to the protection circuit in this amp and the clones like it ?
Wondering since every amp I see like this if the outputs blow the protection doesn't kick in and the amp also blows the power supply fets every time the outputs short ..
And also any fix for the loud turn off pop in these amps ?
Every amp like this that I've seen there is a loud turn off pop
Is there any upgrade to the protection circuit in this amp and the clones like it ?
Wondering since every amp I see like this if the outputs blow the protection doesn't kick in and the amp also blows the power supply fets every time the outputs short ..
And also any fix for the loud turn off pop in these amps ?
Every amp like this that I've seen there is a loud turn off pop
I agree that all the fet should be the same, but isnt the 42N20D 200v 44amps unlike the 31N20D 200v 31amps.
I sometimes use 38N20D with 31N20D when is what i have at hand.
I sometimes use 38N20D with 31N20D when is what i have at hand.
Are you switching off remote while B+ remains at 12v? If so, there should be no pop.
You can reduce the voltage divider threshold resistor to lower the protection circuit threshold for shutting down. In the attached photo, R198 is a 150 ohm. It was originally a 220 ohm. It may be possible to reduce it further (I've gone as low as 100 ohms in some amps).
You can reduce the voltage divider threshold resistor to lower the protection circuit threshold for shutting down. In the attached photo, R198 is a 150 ohm. It was originally a 220 ohm. It may be possible to reduce it further (I've gone as low as 100 ohms in some amps).
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If you switch off power and remote at the same time there will be a pop.
The 220 resistor it is usually in that same location in the other clones?
If not how can we find it in a slightly different amp?
The 220 resistor it is usually in that same location in the other clones?
If not how can we find it in a slightly different amp?
Hey guys, just for S&Gs, I purchased one of those cheapo EBay DIY DSO 138 oscilloscopes (with an "upgraded" 10:1 probe) and a $4 DMM. I searched high and low on YouTube for a serious comparison but found nothing. There are a lot of people on big time budgets or just plain old cheap. I figured I could help them out by providing them results. Not 100% sure where I'm going with this project but I need a hobby. My PA amp was just sitting around collecting dust. I also had the thump when I had it installed in my Suburban. Interestingly, when I reinstalled it in a Scion tC, it only thumped when you had the car on ACC and listening to music then turning it fully on. If you simply cranked it up from OFF, it didn't thump. I didn't put too much thought into it to figure out the "why" portion. That'll be another project to tackle to see if there's a noob way to stop it.
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