Occasional hum

[CageyH]

Last night, and so far this morning, there is a very faint buzz. Almost like the RFI is trying to break through, but can’t quite manage.
It would seem that the culprit is RFI on the aerials, I mean interconnects, on the turntable leads, quite possibly just the earth wire.

Apart from a ferrite, how can I make it less susceptible to RFI?
It is a really thin cable and I have wrapped it round a ferrite I bought for my mains cable.
I am thinking of replacing it with a thicker wire, where I can clip a ferrite on properly. If I do this, I could also shield the cable, or use some RG306(?) coax for the Tt ground and leave the shield floating?

[Macca]

Faraday cage ? Not sure how you'd implement it but it would certainly work.

[CageyH]

Worst case, I could have a fly lead going to mains earth, but the idea of a shielded grounding cable -

I think there is a mobile phone mast about 1km away. This could be the source, but I think I need to stop have an aerial between my TT and Phono-stage.

[Macca]

just get rid of the bloody TT altogether, more trouble than it's worth in more ways than one.

[CageyH]

That would certainly fix the issue.

It is a bit extreme though.

[Macca]

you're a die-hard mate, I will get you a bloodstained undershirt for Christmas.

Funny enough been reading of this same situation with newly-found hum on a few forums lately. All involving turntables. 5G roll-out to blame? Maybe.

[CageyH]

It could well be.

I have just built a TT grounding cable with a floating shield. So far, so good, but it has only been plugged in for 10 minutes.

[Macca]

fingers crossed.

[Barry]

How will a completely floating shield help? It won't act as a Faraday cage.

If you want to use a screened cable, connect the screen at the source: the TT metalwork and leave it floating at the other end.

[CageyH]

From a quick Google.

Does a faraday cage need to be grounded? Grounding a faraday cage — that is, providing a way for the electric charge from its exterior to exit — is important in terms of safety, but it is not necessary for a Faraday cage to operate. Without grounding, electric charge will remain in the exterior of a Faraday cage.

I had this argument with Richard Dunn, but I was arguing that a Faraday cage needed to be grounded. Apparently, it does not.