Z64 Mr. Backup (n64 copier)

[cloudd]

Hi I have modded my Mr. Backup to use a Harddrive instead of the zip drive it came with.  Since a zip drive only requires 5 volts I needed to upgrade the power supply. I check the currents and voltages they are right and it works. But depending on where I plug the power supply is determines whether or not I get this interferance roll on the screen and hum through the audio of the N64.  So for example it works in the livingroom  but gets interference in my bedroom. when I hook the harddrive power to the computers power the mr. backup & N64 have no interference. I have even tried using a computer power supply ripped out of a computer but the the same thing happens when I change rooms in the house.

Would a magnet around the power cable work? I would have already tried that if I had one but I don't.

hmmmm

[NFG]

You might have a ground problem, check to ensure all your grounds are connected to each other, and are not loose or using very thin wire.  Good solid grounds are vital to any system.

[kendrick]

Oh, and for the record? The big chunk of metal you find around power and data cables isn't a magnet, just a big piece of iron. This is what's known as an RF choke, and in some specific instances it will reduce noise and interference. There's some math for determining what size you need and where on the wire to put it, but I don't know it off the top of my head.

-KKC, owner of the mystery Xbox! Does it work? Does it not work? Let's find out!

[Aidan]

It's for common mode rejection - to prevent RF signals travelling up the combination of the wires. It's usually a lump of ferrite (ferromagnetic ceramic material) circling the wires. Generally it's closest to the source of interference, to prevent the cable ending up as an antenna.

[cloudd]

I checked the grounds and they are all connected. But when I use another pc power supply (other than my computers) I get the same problem the interferace.  

[Adeptus]

I've seen something interesting on eBay that may be of use to you...

It's an IDE to USB adapter kit. Basically consists of some software, a USB to IDE cable, and a mains to Molex power adapter.
(ie standard HDD power)

Buy one, use the power brick, sell the rest

[Aidan]

Are you using the same power outlet for the devices? Splitting devices across power outlets can cause potential differences in ground to become obvious (as ground hum). Also, are your power supplies grounded? The ferrite won't help you, as it's designed to combat RF frequencies, not low frequencies.

[Schweino]

Just use a laptop hard drive, which will work fine on 5V. I installed a 8GB laptop hdd in my z64 (using a ide -> mini ide converter) and all works flawless.