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diymod cable problems with ground hum

post #1 of 6
10/4/10 at 9:08am
Thread Starter 

Hi,

 

After I did the diyMod I made a cable with elna caps inside. The cable is to RCA plugs. So I have pins 1+2 going to ground on each RCA plug, and the respective pins 3+4 going to each RCA plug. When I turn on my amp I get a hum. I believe this is a grounding problem. Do I need to ground additional pins? Maybe pin 15? Thanks

 

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post #2 of 6
10/4/10 at 10:08am

no, you do not need additional ground pins. pin 15 if for iphone and itouch; the ipod video has no such accessory mode. sounds to me like the problem is more likely to be in your amp's grounding scheme. pretty much all the ground pins in the ipod are connected on the motherboard, except for serial ground and USB ground,

 

sounds like your amp either doesnt have isolated RCA jacks and there is a ground loop connected through the case, or earth/safety ground and signal ground are directly connected somehow.

 

anyway I suppose it could be a borderline short or other problem with your work on the DIYMOD, too many variables for me to know for sure, but hopefully these educated guesses are of some help for where to start looking

 

good luck

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post #3 of 6
10/4/10 at 11:25am
Thread Starter 

Thanks for the help. It shouldn't have anything to do with the ipod because it makes the hum without the ipod plugged in to the cable. I suspect the cable because when I plug in a standard monster RCA to 1/8" to the same RCA inputs, the hum is gone. I checked for shorts on the cable and there are none.


Edited by knalb - 10/4/10 at 11:27am
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post #4 of 6
10/4/10 at 4:34pm
Thread Starter 

Ah, I resolved the problem. the ipod just needs to be on...

 

very silly.


Edited by knalb - 10/4/10 at 6:07pm
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post #5 of 6
10/4/10 at 8:13pm

hahaha indeed yes it does

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post #6 of 6
10/5/10 at 3:40am

Easy solutions are always the best!!

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