Need helps with hums, radio station in phono


My room seems to have all kinds of problem with some phono units. In the past, I had quite a bit of problem with getting radio station noise in some phono units but not others. The biggest problem seems to be in my Io Eclipse. I used to be able to fix it by connecting ground lead from tonearm to ground on SUT first (signal went straight to Io). Then last month or so radio station noise came back again and there is nothing much that help short of removing tubes from 3rd stage and reduced gain to 50 dB then use a SUT in the pathway. Sonically, I had not complain with using Dynavector 1:13 SUT although overall the gain is a tad on the high side. With Reed tonearm, I am still quite happy with the result.

Recently I installed Graham arm on my turntable and it gave a new hum problem. As soon as cartridge touch LP, I get quite a bit of a hum but no hum when the needle is lifted. I did not have this problem with Reed. I tried moving Io around as much as my shelf/cable/AC cords allowed. Playing with ferrite thing around cable, lift ground from AC, float ground on SUT, trying placing ERS paper around SUT, cables, Io, connecting ground cable from chassis to chassis of isolated transformer, nothing works. Everything I have is plugged into a power conditioner and Isoclean Isolated transformer. Sometimes the hum went away for a few days then it came back again. My Lamm phono has no such problem. I still really like Io Eclipse sound very much and definitely wants to keep it but I am at my wit's end.
I was told that Versa Dynamic used to make something that supposed to help with this problem but have not been able to locate any on Ebay or a'gon.
suteetat
I only have ground from tone arm to Sut. I played around a bit with ground wire from motor unit and plinth to isolated transformer ground that did not do anything. I use tw black Knight Battery power/speed controller on my Raven AC 1 turntable. I tried both with ground lead connected and disconnected between Sut and Io. Tw and Io is plugged into the same conditioner that went to the same isolated transformer. I am not sure it this is a ground loop problem as groundloopmproblem that I saw in the past tend to be there all the time even when music is not playing. In this case, I only get the hum if the needle is playing.
This is weird but will work-
Get a ferrite core and wrap it around your power core. All your radio interference wil be gone.

Here's an article:

Ferrite cores are small semi-magnetic iron pieces encased in a plastic snap enclosure. Designed to fit around power cords and interconnects, they block electromagnetic interference and unwanted high frequency information. Since ferrite shields can often affect these frequencies in the analog domain, it is usually used for digital and power cables where frequency manipulation is not audible. Ferrite cores have been used for years in the engineering, computing, and electronics industries
Sorry-just saw you tried the ferrite core...did you try one on every power cord? wrap it twice? good luck.
You don't have a ground wire tied to your turntable? I have a Basis and VPI tables and both of them have a ground wire attached to the steel hub that seats the platter bearing under the turntable, as well as a ground for the tonearm.
Tbromgard, I tried it only with phono cable as I use Stealth Dream AC cord on my phono unit, not sure where I would find ferrite ring that big!.

Jmcgrogan2, hmmm... thanks about ground between phono adn bearing hub. I never tried that before and will talk with TW as I am not sure how to connect that. My VPI table does have that but I never had to use it before.