Any body have board schematic for Rockford Fosgate 800a2?

[rockfordfanatiq]

anybody have a schematic for a Rockford Fosgate punch 800a2 ?
Board # pc-2038-c

please email to swansond@vmcmail.com

thanks

 

[Perry Babin]

See attached.

 

[rockfordfanatiq]

thank you very much Perry!!

 

[rockfordfanatiq]

now my question is< q3 and q4 were both burnt. as i would power it up it would blow the 10amp fuse. replaced the q3 and q4 transistors. now it will power on but it seems they still are getting hot which makes me believe something else is wrong. i removed c2 and c18 capacitors because i believe they are both bad. would that cause Q3 and Q4 transistors to get hot and burn up?

 

[Perry Babin]

Shorted power supply FETs?

 

[rockfordfanatiq]

I don’t believe so. They all tested out ok however I guess that doesn’t mean anything right.

 

[seankane]

What are the readings in ohms using your meter from gate to source on the power supply FET's?

 

[Perry Babin]

Do they heat up without B+ applied?

Is D6 or D7 shorted?

Are you sure that you installed the NPN and PNP driver transistors in the right locations?

 

[rockfordfanatiq]

Perry, hate to sound stupid but I’m not really sure. Didn’t really realize they were different until now. Just looked at the schematic. When I ordered and replaced them I just automatically assumed they were they same transistors. Now I’m going to have to go back and check them. I will also check the ohms at the mosfets and see what they read. Will get back on it tonight when I get home from work. Thank you for the input! And I’ll let you know how it goes.

 

[rockfordfanatiq]

C2 and c18 capacitors has white residue around the bottom of them which is why I figured they would need replaced. I will also check d6 and d7 tonight.

 

[rockfordfanatiq]

d6 and d7 seem to be fine assuming i was testing them correctly. Q4 I did however have a pnp in place of the npn that needs to be there so i will have to order some of those.
As for power supply mosfets,
Q15-452.1 k ohm
Q16-452.1 k ohm
Q17-452.1 k ohm
Q18-452.1 k ohm
Q33-.668 m ohm
Q34-.668 m ohm
Q35-.668 m ohm
Q36-.668 m ohm

Q12-650.6 ohm
Q30-244.0 ohm

Q14,Q13,Q31,Q32 I do not know how to test.

And yes, either Q3, or Q4 do heat up without b+ applied.

 

[rockfordfanatiq]

After doing some looking on the schematic. I removed c18 capacitor to replace due to it having a white residue around the bottom of it. I have noticed the capacitor I removed is a 35v 10uF, but the schematic shows it being a 16v 10uF. I went ahead and ordered both but not really sure what I should replace it with. Should I put the 35v back in it or go with the 16v?

 

[Perry Babin]

35v

 

[rockfordfanatiq]

Ok put 35v 10uF capacitors in, changed out the q4 with the correct npn transistor. Now upon powering it up q5,q6,q7,q8, are getting hot right away at power up. Also Q3 and Q4 transistors are also getting hot.Tried powering it with a 10amp fuse and it blowes it right away. Dont know what else to look at, at this point.

 

[Perry Babin]

Do not connect B+. Do you see a good drive signal at the gate of all of the power supply FETs?

 

[rockfordfanatiq]

Q18-5.28v
q17-5.28v
Q16-5.28v
Q15-5.28 them are the ones getting hot
on the other side of the board
Q36-.231v
Q35-.231v
Q34-.231v
Q33-.231v

 

[rockfordfanatiq]

q36-q33 do not get warm at all

 

[Perry Babin]

Replace the other 2 PS driver transistors.

 

[rockfordfanatiq]

so that would be Q1 and Q2?

 

[Perry Babin]

yes