The power supply fets are RFP70N06 would you recomemd sticking with those fets or is there a better replacement ?
Hi , I repaired this amp with new mosfets and output transistors . The amp turns on and plays but for some reason I keep shorting out the sound cards and I can’t figure out why ?
Can anyone help me ?
Can anyone help me ?
Please don't post in a repair thread that was started by someone else unless you are trying to help them.
Start a new thread if you need help with a repair of your own.
Start a new thread if you need help with a repair of your own.
I’m working on this amp again .
Does anyone has a close up pic of this area or the bottom side of the board ?
Leg 1 of the transistor has no trace going to it since it was burnt off the board .
I can’t seem to figure out what leg 1 of that transistor connects to
Does anyone has a close up pic of this area or the bottom side of the board ?
Leg 1 of the transistor has no trace going to it since it was burnt off the board .
I can’t seem to figure out what leg 1 of that transistor connects to
Attachments
Ok I see where leg 1 goes now in the schematic .
1 transistor is a A56 on the opposite side of the board I believe is going to the positive 15 volts
Would the transistor going to the negative 15 volts be an 06 or would it still be a 56 do you happen to know ?
1 transistor is a A56 on the opposite side of the board I believe is going to the positive 15 volts
Would the transistor going to the negative 15 volts be an 06 or would it still be a 56 do you happen to know ?
The drive in this PS is an H-bridge. It has 4 banks of FETs for one transformer. The 4081s drive 2 banks each.
The FETs in some if the PPI amps are intertwined so the FETs alternate from one bank to the other instead of being in groups.
The FETs in some if the PPI amps are intertwined so the FETs alternate from one bank to the other instead of being in groups.
Replaced the Hip4081 ic’s and on 2 banks of fets I get no drive signal .
Do these have a high failure rate also like the 4080’s ?
Or any ideas on what worse to check since I get no drive at all on 2 banks including Q1,2,3,4,5,6 and Q69,70,71,72,73,74
I have a nice square wave when the ic isn’t loaded as soon as I load the 4081 with a fet the drive goes away
Do these have a high failure rate also like the 4080’s ?
Or any ideas on what worse to check since I get no drive at all on 2 banks including Q1,2,3,4,5,6 and Q69,70,71,72,73,74
I have a nice square wave when the ic isn’t loaded as soon as I load the 4081 with a fet the drive goes away
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