Hi there!
I have trouble with the amp of my brother.
He told me that the right rear channel isn't working properly. (much distortion)
When I play a 100Hz Sine wave the RR Channel lookes like this:
after a little search I found out that Q323 and Q310 are shorted, the source resistors R380 and R336 are open, the resistors R382 and R383 are open and the drivers Q321 Q322 are shorted.
After changing this parts, the sine wave won't look better 🙁
It looks like this on every of the 4 IRF540 (checked at the middle leg)
Can you help me with this?
-> I found out that Q309 is getting hot.
I have trouble with the amp of my brother.
He told me that the right rear channel isn't working properly. (much distortion)
When I play a 100Hz Sine wave the RR Channel lookes like this:
An externally hosted image should be here but it was not working when we last tested it.
after a little search I found out that Q323 and Q310 are shorted, the source resistors R380 and R336 are open, the resistors R382 and R383 are open and the drivers Q321 Q322 are shorted.
After changing this parts, the sine wave won't look better 🙁
It looks like this on every of the 4 IRF540 (checked at the middle leg)
An externally hosted image should be here but it was not working when we last tested it.
Can you help me with this?
-> I found out that Q309 is getting hot.
Last edited:
What is the PC number for that amp?
Lift 2 legs of D302. Does that allow the amp to produce clean audio?
Lift 2 legs of D302. Does that allow the amp to produce clean audio?
When the diode was in the circuit, was the signal distorted when there was no speaker or dummy load connected to the channel?
I'm working from a schematic diagram that I assumed was the same (or close enough). Contact Rockford to get the correct schematic diagram and email me a copy of it.
babin_perry@yahoo.com
babin_perry@yahoo.com
Hi Perry,
did you get my email?
Rockford told me that the PC3095-B is the same as the PC3095-A.
They send me the schematic I have attached.
I'm wondering that the rear right channel should be the 4xx components.
my rear right channel uses the 3xx components....
http://www.soelkweiler.de/RoFo/H18004_PC-3095A-1.pdf
did you get my email?
Rockford told me that the PC3095-B is the same as the PC3095-A.
They send me the schematic I have attached.
I'm wondering that the rear right channel should be the 4xx components.
my rear right channel uses the 3xx components....
http://www.soelkweiler.de/RoFo/H18004_PC-3095A-1.pdf
My internet connection has been down most of the night.
The numbers are the same as the diagram that I had. Those are the only 3 transistors that I see that can cause the amp to clip the bottom half of the waveform if the amp produces clean audio up to clipping with a load when D302 is out of the circuit. Confirm that all of the resistors in that part of the circuit are within tolerance.
The numbers are the same as the diagram that I had. Those are the only 3 transistors that I see that can cause the amp to clip the bottom half of the waveform if the amp produces clean audio up to clipping with a load when D302 is out of the circuit. Confirm that all of the resistors in that part of the circuit are within tolerance.
I have had many Rockford amps with the problem you are having, caused by a bad SMD resistor.
Check all the ones in that circuit, if you find one way off remove it from the circuit and test it to be sure. You will find it.
Check all the ones in that circuit, if you find one way off remove it from the circuit and test it to be sure. You will find it.
I found out that R338, a 10Ohm resistor, was also open.
But even after changing it, the problem is still the same 🙁
I have checked many other resistors (measured in circuit) and compared it with the resistors from the front channel.
I can't find any other resistor with wrong values.
The only strange thing is R340. it should be 91k Ohm and that is exactly what my multimeter told me.
But R140, R240 and R440 shows me only 44k Ohm. (all measured in circuit)
Can this help to find the defective parts?
But even after changing it, the problem is still the same 🙁
I have checked many other resistors (measured in circuit) and compared it with the resistors from the front channel.
I can't find any other resistor with wrong values.
The only strange thing is R340. it should be 91k Ohm and that is exactly what my multimeter told me.
But R140, R240 and R440 shows me only 44k Ohm. (all measured in circuit)
Can this help to find the defective parts?
R341 - 1000Ohm
R342 - 999Ohm
R343 - 39,5k Ohm
R141 - 994Ohm
R142 - 995Ohm
R143 - 30,5k Ohm (same as R243 and R443)
R342 - 999Ohm
R343 - 39,5k Ohm
R141 - 994Ohm
R142 - 995Ohm
R143 - 30,5k Ohm (same as R243 and R443)
When you set your scope to 5v/div and touch the probe to the positive output terminal of your power supply, does the trace deflect up approximately 2.5 divisions?
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