It's best to have a grounded shield on the head unit. You'll miss lots of problems if you don't. I had an amp in here tonight that would have been considered OK if I wouldn't have had a shield ground.
I'd recommend that you repair the shields by jumping from the shield to the case of the head unit. To protect the wiring, you can use 1-3 amp fuses in the jumpers.
I'd also recommend cutting the shield of the RCA cable and inserting an automotive brake lamp in the shield (one side (head unit side) of the shield to the ground of the lamp, the other side of the shield to the terminal on the end of the lamp). If there is 12v on the amp shield (in the case of transformers shorted primary to secondary), the lamp will light. If you allow the shield to contact the power wire on the bench, the lamp will light.
You should also insert a 10uf (value not critical, preferably non-polar) in each channel where you cut the RCA cable to insert the lamp in the shield. This will protect the head unit's muting transistors if the center conductor contacts 12v.
I'd recommend that you repair the shields by jumping from the shield to the case of the head unit. To protect the wiring, you can use 1-3 amp fuses in the jumpers.
I'd also recommend cutting the shield of the RCA cable and inserting an automotive brake lamp in the shield (one side (head unit side) of the shield to the ground of the lamp, the other side of the shield to the terminal on the end of the lamp). If there is 12v on the amp shield (in the case of transformers shorted primary to secondary), the lamp will light. If you allow the shield to contact the power wire on the bench, the lamp will light.
You should also insert a 10uf (value not critical, preferably non-polar) in each channel where you cut the RCA cable to insert the lamp in the shield. This will protect the head unit's muting transistors if the center conductor contacts 12v.
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Perry,
I did as you said on this unit. I must have something else going on all amps i test on it do the same thing the speaker flutters back and fourth.
I might just go buy a cheap test deck since this one is really old and i dont have much time to trouble shoot the thing since i have 100 amps sitting here for repair right now.
I did as you said on this unit. I must have something else going on all amps i test on it do the same thing the speaker flutters back and fourth.
I might just go buy a cheap test deck since this one is really old and i dont have much time to trouble shoot the thing since i have 100 amps sitting here for repair right now.
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