Hello, I have a Rockford rf2002 amplifier that has a nasty alternator whine NO MATTER which system it's attached to, and nothing solves it. I unhook it, and the whine goes away. The whine is system wide and goes away when I disconnect the amplifier. What electronic components could be faulty? A schematic would help.
What's the PC# on the circuit board?
With nothing connected to the amp, what's the resistance from the input RCA jack shields to the main ground terminal?
With nothing connected to the amp, what's the resistance from the input RCA jack shields to the main ground terminal?
There is no resistance. The meter beeps. Where on the board do I find the pc#?
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It sounds like it has a shorted diode but I need the PC # to see if I have a diagram for it. Or, you could get it from Rockford's tech support.
That's it. You'll have to get it from Rockford or from someone else here. In the attached diagram, you can see two diodes marked ED, D5 and D6. Do you have anything similar (near the TL494 IC)?
Does one read 0 ohms to ground on both terminals?
Does one read 0 ohms to ground on both terminals?
The big diodes on the right and bottom of the picture? I tested those and there's resistance in the kiloohms.
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A diode in the alternator may be blown. Have a look with an oscilloscope to see what the waveform looks like.
If you don't find anything wrong with the amplifier, and all your cables are properly shielded and making good connections, go with a ground star approach. Run all system grounds to one place. So that implies insulating the chassis of all equipment in the system from the car with the exception of maybe the head unit if the star ground point is located there.
And you read 0 ohms from the RCA shields to the primary ground with NOTHING connected to the RCA jacks?
^^^ double-check.
^^^ double-check.