Nude Turntable Project

Dover wins the Kewpie Doll...🎉💇
When I changed the support of my Victor to the steel cradle two years ago, I removed the flimsy perforated metal screen surrounding the 'guts'.
Well it turns out that this metal screen was acting as a Faraday Cage for the electrical emissions from the motor power supply.
Without the screen absorbing and neutralising this energy.....the cartridge apparently picks up the 50/60Hz emitted frequency at very loud amplification levels (I can't imagine that the platter is vibrating at this frequency?).
This is why there is no feedback issue with my primitive (sorry Aigenga 😏) original support system.
And yes.....when I place the Victor into the granite cradle with the screen attached.....no feedback 😃‼️

This however gives me a dilemma.....I would prefer not to have the screen attached as there are audible benefits without it. I also don't believe the screen is as effective (being tight up against the granite inner wall) as I believe a Faraday Cage should have both sides of the metal screen in free air?
I have orderred Mu Metal sheet and wondered if this was a possible alternative to the Faraday Cage?
Is it OK to wrap the power supply transformer in Mu Metal or will it get too hot?
Would it be better to line the inside of the granite cradle with the Mu Metal instead (or also)....or am I doomed to using the metal cover forever?

Hi Chris,
It may be the camera angle....?
I think the Dyna is riding just fine...😎
I hate removing the word 'Nude' from any sentence......😰

Halcro, the can on my tt-101 is heavily damped with bituminous automobile noise suppression sheets, it is also wrapped with a fat rubber band and as I said I use a cone (more like fat cylinders with sharp points) dead center to further drain it. So while it looks primitive compared to the granite clerical collar (but far less primitive than letting it all hang out) it is actually fairly sophisticated.

I use a mu metal shield under the platter, covering the motor.

Halcro
Is there a secondary issue here?

" ..a low frequency drone begins and then increases in volume.."

Could there be acoustic feedback following the initial EMR problem?

Cheers

Halcro - if the cover is tight, then I would run an earth wire to the cover and then just push it into the cylinder leaving a gap at the top such that it doesn't touch the main TT. As long as the cover is grounded to discharge any electrical buildup it works. You could spray some damping compound on the inside of the cover if you want to get rid of any mechanical noise.

It is also possible that the tonearm & tonearm cabling could be picking up rf from the motor.

A small point on earthing - I usually find I get a lower nose floor if I run the TT earths ( i.e. chassis, motor etc ) to ground through the power cable to wall if possible and run only the tonearm earth to the phono/preamp. In a single ended system noise from grounding or shielding is effectively in the signal path.