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Author Topic: A/v Interference  (Read 55 times)

M3ATW0D

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A/v Interference
« on: January 13, 2005, 11:46:00 PM »
So I've had this xbox for awhile now with no problems. Recently I've notice it now has bad interference, after extensive troubleshooting I am beginning to suspect the PSU as the reason.  I've heard a bad electrolitic capacitor can cause this on the PSU.  I just want to possible confirm this with the techy experts before I go ripping my case apart (again), lol. Thanks to all.
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spillage

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A/v Interference
« Reply #1 on: January 14, 2005, 02:24:00 PM »
Sounds to me like you have either an earth loop or a screen down. Have you changed anything in your setup recently, including moving stuff around?? Has your household bought any new applicances recently? The PSU fault although possible seems unlikely to me. IMO the distance between the PSU and the encoder is sufficent to rule this out. By distance I don't mean cm/inches, I mean population of mobo and trace routing via caps etc. The encoder is too far downstream for video noise to effect it. If the encoder was fed by it's own supply rail then I would agree with your suggestion.

I would move your box away from everything else and try again. Tap the cable and the rear of the box gently and note any clicks or pops on the display.

If you are using an AV amp as a switcher, then disconnect the other feeds the display and try again. If you have an earthed power amp, connected to the processor by cable screened at both ends, pull the mains from the power amp and try again.

Post back your findings.
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PhatheadWRX

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A/v Interference
« Reply #2 on: January 14, 2005, 05:52:00 PM »
Not to thread jack, but I recently did a PC case conversion and today XBMC started to have an audio hum.

I use an Apache 2.0 from tribemods for the 300W PSU -> Xbox.  I have tried to contain all power wires under my DVD drive.  There are however power wires that run around the MB to power fans.

The only thing I changed before after the hum was remove my large Maxtor HD and replace with a WD 160.  I have a dual HD setup with the stock WD drive.

So Spillage, you said that the issue is not the PSU? but from other interference?
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M3ATW0D

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A/v Interference
« Reply #3 on: January 14, 2005, 07:19:00 PM »
tongue.gif  could it be just time for something to go bad?
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M3ATW0D

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A/v Interference
« Reply #4 on: January 14, 2005, 07:25:00 PM »
btw i have 3 xboxes all within the same area and only one gets interference. i've changed all the eternal parametrs so it leads me to think it is inside.
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zweef_jr

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A/v Interference
« Reply #5 on: January 15, 2005, 02:51:00 AM »
i have the same problem, but i think it's a ground loop.
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M3ATW0D

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A/v Interference
« Reply #6 on: January 15, 2005, 11:14:00 PM »
with no shielding, is it possible that the ground pads on the psu and mobo my need to be jumped with a wire so share a common ground?  just a thought.
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spillage

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A/v Interference
« Reply #7 on: January 16, 2005, 03:53:00 PM »
smile.gif

If you have more than one box swap out a PSU and see what happens.

I would be very interested to hear what you find.

Are you using the proper XBOX mains lead with the ferrite choke? If not get one. SM PSU's are notoriously noisy and PSU switching noise could be transmitted down the mains fed and into the TV or other connected equippment causing your issue.
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