PPI PC21400.2

[caraudioguy2100]

Anyone have a pic of this area ?

 

[Perry Babin]

See attached. A 2350, the closest I have.

 

[caraudioguy2100]

The power supply fets are RFP70N06 would you recomemd sticking with those fets or is there a better replacement ?

 

[Perry Babin]

Those are good enough. 3205s would be only marginally better.

 

[Relax3030]

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 ?

 

[Perry Babin]

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.

 

[caraudioguy2100]

Back to this amp .

Anyone know the value of the rail caps ?

 

[Perry Babin]

In the 2350, they are 2200@63v.

 

[caraudioguy2100]

Does anyone know what transistor this is an A06 or 56 ?

The other side of the amp is an A56

 

[caraudioguy2100]

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

 

[Perry Babin]

See attached.

 

[caraudioguy2100]

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 ?

 

[Perry Babin]

What's the circuit board designation of the transistor you are unsure of?

 

[caraudioguy2100]

Not sure what the board location is . Since it’s burnt in that area .

The other side of the amp is pretty much the same circuit and Q60 is an A56


Here is a pic of where the transistor goes it sits in front of CR17

 

[Perry Babin]

You could have looked at the other side and used the process of elimination.

Q31?

 

[caraudioguy2100]

Yes Q31

 

[Perry Babin]

Yes. A06.

 

[caraudioguy2100]

Are the HIP4081’s the driver ic’s for the power supply fets or what do they control ?

 

[Perry Babin]

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.

 

[caraudioguy2100]

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