Grounding radio equipment

[da na]

I have a little InfOSpot AM radio transmitter that, along with its audio, transmits a loud 60hz buzz. When a recieving radio is held or placed against something grounded - water pipes, etc, the buzz goes away. I would assume the hum is due to grounding, as the transmitter is not grounded (it runs off a cheap little 12v AC-DC converter box with no 3rd pin). Running the transmitter on battery power almost completely erases this hum, but that's not a good long-term solution. I'd like to know how to go about grounding the transmitter - or the antenna. The proper AM transmission antenna grounding involves a several-foot pole shoved in the earth, but I cannot do that.

First thought was just wire the antenna straight to the ground plug of an IEC cable and plug the antenna into the wall for grounding. Is that safe? Don't want any power going from the wall up the antenna and into the transmitter.

Next idea is unraveling my coil antenna and wrapping its copper wire around a water pipe for grounding.

There's probably a better solution than either of those, though. Any ideas would be appreciated!

[LloydLynx]

Either a water pipe or jam a wire into ground in an outlet. As long as the outlet is wired correctly, just avoid live and you're safe. Or wrap a wire around the plate screw of an outlet, same thing.

[ImorallySourcedElectrons]

What a lot of folks do to create a good ground for their transmitters is to throw some chicken wire into the ground. If you do it well you can hide it in your lawn, plenty of instructions in amateur radio community.

[da na]

11 minutes ago, ImorallySourcedElectrons said:

What a lot of folks do to create a good ground for their transmitters is to throw some chicken wire into the ground. If you do it well you can hide it in your lawn, plenty of instructions in amateur radio community.

Would love to but I live on the 16th floor of an apartment building. 

26 minutes ago, LloydLynx said:

Either a water pipe or jam a wire into ground in an outlet. As long as the outlet is wired correctly, just avoid live and you're safe. Or wrap a wire around the plate screw of an outlet, same thing.

Great, thanks!

[ImorallySourcedElectrons]

20 hours ago, da na said:

Would love to but I live on the 16th floor of an apartment building. 

If the building has a metal frame element you have access to, you could try using that as grounding point.

[baked jonkler]

The hum is 100% from your power supply. Look into a grounded liner unit if you can. Being up that high i wouldn't use the outlet ground as it will act as a counterpoise to your antenna. Station grounds need to be as short as possible and no longer than the antenna itself. Maybe an artificial ground from MFJ or a similar supplier?

[da na]

3 hours ago, baked jonkler said:

The hum is 100% from your power supply. Look into a grounded liner unit if you can. Being up that high i wouldn't use the outlet ground as it will act as a counterpoise to your antenna. Station grounds need to be as short as possible and no longer than the antenna itself. Maybe an artificial ground from MFJ or a similar supplier?

Hum still happens on batteries, so I would rule the power supply out.