I have just been given an old Pioneer receiver. On the back there is a grounding screw and I was wondering where it is supposed to hooked up. I thought maybe it is to be connected to the electrical box where the unit plugs in. Would this get rid of the hum that is in the background? Thanks in advance for your assistance.

Have you tried wrapping the wire around the little screw that holds the electrical plate?

Do you have a pic of the back of the rec?

Most all old recievers have a grounding screw allowance for a turntable.
You do not specify if you are using one but if you are then it needs to be grounded to the reciever.
If you are using the reciever for other purposes and it is still hummimg then you may have phase/loop issues explained pretty well in these two threads.


http://www.ftatalk.com/showthread.php?t=258889&highlight=humming+audio

http://www.ftatalk.com/showthread.php?t=241391&highlight=humming+audio


good luck
peace ....just humming along.

If it's an older receiver with a non-polarized AC plug, (one pin bigger than the other) try flipping it around at the AC wall socket, this will reverse the AC (hot/neutral) going into the receiver, this may or may not fix the problem. One other thing that could be causing the buzz is dried out DC electrolytic filter caps in the power supply, they tend to dry out after a few decades.

Something else to check is your speaker wiring... If your speaker wires are run near AC power wiring they could pick up the 60hz frequency and cause a hum in your speakers.

is a cell phone near the receiver?

Funny you mention that Buf... Whenever I get a call on my cell, my computer speakers go nuts... Almost like morse code coming out of them.