Kicker IX1302

[m4ick]

Also, when I say disconnecting voltage regs brings it out of protect, I mean I see PS drive signal and rail voltage.

 

[Perry Babin]

Pull that transistor.

Reinstall the jumpers that you removed earlier.

Are the power supply FETs in the circuit?

 

[m4ick]

Will do.

They've been installed since post #15, without them installed it is not in protect.

Since post #12, 1 per bank.

I'll get back to you shortly, thanks for your time Perry.

 

[m4ick]

With the amp in it's factory state, except 1 fet per PS bank and Q704 removed, the amp powers on. Shunt resistors on the regs get hot pretty dang quick, may be normal but within seconds they are hot, in a minute or two I can hardly touch them.

 

[Perry Babin]

Clamp all transistors to the heatsink.

Insert either a current limiter or a 10 amp fuse in the B+ line.

Power up the amp. Does it blow the fuse or drag the voltage down significantly through the 2 ohm resistor?

If it does neither of those, does it produce audio?

 

[m4ick]

No heat sink mounted components are getting hot.

10 amp done.

11.88V at the power terminals.

Nice and loud.

Guess the op-amps are good! Heheh.

 

[m4ick]

It produces audio without the transistor tied to pin 4 of the 494, but it sill goes into protect with the transistor installed. Not sure what to look for next.

 

[Perry Babin]

Check the connections between the transistors in the power supply area. Do these numbers match the numbers match those in your amp?

If not, find the corresponding transistors for the 4 in the image below and to the left of the 494 and post what they are like this:

Q704 = Q...

 

[m4ick]

I was looking over that schematic earlier. The four transistors to the left have identical designations.

 

[Perry Babin]

Reinstall Q704 and remove Q706.

Does it produce audio??

 

[m4ick]

With Q704 in circuit and Q706 out it is back in protect again.

 

[Perry Babin]

Remove Q705. Does that allow it to produce audio?

 

[m4ick]

Q706 and Q705 out of circuit, still in protect.

 

[Perry Babin]

Remove Q704 and Q703. Check both carefully, confirming that neither is leaking and that both have 2 good PN junctions.

 

[m4ick]

I replaced both Q704 and Q703 with new KTA1266GRs, still in protect It did power up with Q703 out of circuit.

 

[Perry Babin]

Do you have 12v on one end or R706?

 

[m4ick]

I have 11.5v on one end and 5.8v on the other.

11.9v at the power terminals.

 

[Perry Babin]

Is Q705 still out of the circuit?

If so, post the DC voltage on all 3 legs of Q703 and Q704.

 

[m4ick]

Q703

B: 4.41v
C: 0v
E: 5.7v

Q704

B: 5v
C: 2.7v
E: 4.41v

Q705 and Q706 are out of circuit.

 

[m4ick]

Oops, i think i have BCE reversed.