R55 and R56 are burned and cannot be read. They each tie the middle leg of a TIP41C or TIP42C to the rails respectively. Any idea what their values may be? It appears to possibly be the voltage regulator circuit.
ZD4 appears to be near 0 ohms while ZD5 reads 950 in one direction (diode check) and OL in the other. Could the one shorted zener burn the resistors in both + and - voltage regs?
Uh oh, just found an op amp cracked in half. It all op amps read 340 from vcc+ to vcc- on diode check. I'll remove the one op amp and see if it corrects the leak.
I don't have a 2068D on hand, would a 4558P suffice for testing?
I don't have a 2068D on hand, would a 4558P suffice for testing?
OK, new summary.
Voltage regs are shot with one shorted zener on one side and R55 and R56 are burned, one in each regulator.
I found a blown op amp that made all op amps read 340 both ways from vcc- to vcc+. With the burned op amp removed I place the + probe on VCC- and negative on VCC+ and get about 640 on diode check, with them reversed i see a cap charging and it reaches OL eventually. Much improved over 340 both ways. These tests were done with the op amp board disconnected from the amp.
At this point I need the value of R55 and R56 in the voltage regulator, I cannot read them at all. I also need to know if I can replace a 2068D with a 4558P so I can test this thing.
Voltage regs are shot with one shorted zener on one side and R55 and R56 are burned, one in each regulator.
I found a blown op amp that made all op amps read 340 both ways from vcc- to vcc+. With the burned op amp removed I place the + probe on VCC- and negative on VCC+ and get about 640 on diode check, with them reversed i see a cap charging and it reaches OL eventually. Much improved over 340 both ways. These tests were done with the op amp board disconnected from the amp.
At this point I need the value of R55 and R56 in the voltage regulator, I cannot read them at all. I also need to know if I can replace a 2068D with a 4558P so I can test this thing.
Email or call kicker for the value of the resistors.
The 4558 may work but you should use an exact replacement if you're repairing this for a paying customer.
The 4558 may work but you should use an exact replacement if you're repairing this for a paying customer.
Ok, will email or call kicker. The regulators have 3.3k ohm resistors and then the burned ones. My best guess looking at other amps is 100ohms for the burned resistors, but I will find out for sure.
I figured the 4558 would work but the 2068 is newer technology and has better specs, I plan on repairing the regulators (should have all parts on hand) and testing to see if any other op amps have failed. Then testing with the 4558 for output. Then I will order some 2068s and parts for the MTX 81000D.
And yes, this one is for a paying customer.
One last thing, if I replace the resistors and the shorted zener is it safe to power it up to determine if the TIP41/42Cs are operating correctly or would it possibly destroy more op amps?
EDIT: I can leave the crossover/gain board out of circuit for testing on the regs.
I figured the 4558 would work but the 2068 is newer technology and has better specs, I plan on repairing the regulators (should have all parts on hand) and testing to see if any other op amps have failed. Then testing with the 4558 for output. Then I will order some 2068s and parts for the MTX 81000D.
And yes, this one is for a paying customer.
One last thing, if I replace the resistors and the shorted zener is it safe to power it up to determine if the TIP41/42Cs are operating correctly or would it possibly destroy more op amps?
EDIT: I can leave the crossover/gain board out of circuit for testing on the regs.
IF the Zeners are in the circuit, it should be safe to power the amp up if the TIP transistors are not leaking badly or shorted.
Still waiting to hear back from kicker.
This photo is from the Kicker KX350.2. The part designations are the same as in the ZX450.2. I have replaced R55 and R56 with 10ohm resistors but what are the diodes? All I can make out is the number 15 and the number 2 which I imagine means is just a 15v zener, would a 1n4744 work in its place?
This photo is from the Kicker KX350.2. The part designations are the same as in the ZX450.2. I have replaced R55 and R56 with 10ohm resistors but what are the diodes? All I can make out is the number 15 and the number 2 which I imagine means is just a 15v zener, would a 1n4744 work in its place?
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Kicker just emailed me a list of components for this amp, would you like me to e-mail it to you Perry?
R55 and R56 were 10ohm 1/4w, I had some wire round 10ohm resistors on hand, and the zeners are NEC RD15EB3 0.5W 15V, replaced them with 1N4744A (1W equivalent).
I now get +-14.8, installed the crossover/gain board and it did not draw excessive current or heat up, I installed a 4558 in place of the 2068 and voila! Audio! All I need now is some 2068s and this thing is done!
Again, let me know if you would like me to e-mail you the component list for this amp.
R55 and R56 were 10ohm 1/4w, I had some wire round 10ohm resistors on hand, and the zeners are NEC RD15EB3 0.5W 15V, replaced them with 1N4744A (1W equivalent).
I now get +-14.8, installed the crossover/gain board and it did not draw excessive current or heat up, I installed a 4558 in place of the 2068 and voila! Audio! All I need now is some 2068s and this thing is done!
Again, let me know if you would like me to e-mail you the component list for this amp.
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