So I got a composite+dual-mono modded original Famicom from this seller on Yahoo Auctions:
https://auctions.yahoo.co.jp/seller/slbh280
I already have an RGB modded AV Famicom and an AVS, but the auction was cheap and I wanted the original Famicom for stuff like JP Zelda and games that use dithering to simulate transparency over composite.
When I hooked up the Famicom composite to my PVM and the audio direct to my receiver, I got a huge amount of what sounds like ground loop hum that almost totally drowns out the Famicom audio, and inserting/removing audio cables makes extremely loud sounds that could blow out speakers.
The thing is though, nothing was connected to ground (not the PVM, the Famicom, the receiver, or anything in my apartment other than my wash machine; we never have power surges in Tokyo so usually the only things grounded are huge appliances).
Tried hooking up the Famicom composite direct to the receiver, and the hum went away, so I assume it's not a problem with the Famicom...
Tried different RCA-BNC adapters, switched from input A to B on the PVM, but couldn't get rid of the hum.
Any ideas?
Ground loop hum from Famicom when nothing is grounded?
Re: Ground loop hum from Famicom when nothing is grounded?
Did some more testing.
Seems the audio is also fine when I route everything through my Framemeister. Only get a ground loop hum when I use my PVM, but I've never had any problems with ground hum before, even when I use composite (which is admittedly rare).
Guess I'll try actually connecting my PVM to a grounded outlet...
Seems the audio is also fine when I route everything through my Framemeister. Only get a ground loop hum when I use my PVM, but I've never had any problems with ground hum before, even when I use composite (which is admittedly rare).
Guess I'll try actually connecting my PVM to a grounded outlet...