How to eliminate FM RF coming thru turntable?


Mitchell GYRO SE turntable picking up FM RF after 5 PM to late at night. During the day, no FM RF being picked up by turntable. All other components, no RF (tuner, CD, tape). All components connected thru Furman power conditioner. Have run separate ground from Furman to turntable ground at preamp (Rogue 99) which reduces the FM RF considerably, but does not eliminate. FM interference reacts to volume control. FM RF disappears when turntable leads disconnected. Any suggestions?
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How about the other suggestion I had made, adding a small amount of capacitance via a y-connector at the preamp inputs (the capacitors being soldered to rca plugs that would plug into the y-connectors)? As I indicated, the only caveat would be to make sure you are staying within the range of total load capacitance recommended by the cartridge manufacturer. If you have a moving coil cartridge, load capacitance is most likely very non-critical.

Regards,
-- Al
Copper is a lot safer than lead, and would provide the same benefit. If you go this route research the term, "Faraday Cage", which is a lab quality box. The problem is that you need cables going in/out and that often corrupts the ability keep out the RFI.

Borrow a solid state phono stage before you conclude anything else or spend big bucks. Trust me, I struggled w/this crap for YEARS! Cheers,
Spencer
Al & Spencer thanks for your input.

Al -- my cartridge is a Grado MM. Would you please exlaborate what sort of capacitors to use. I'm not too electronically literate.

Spencer -- I did hook up to a solid state phono stage. Did get RF, but was able to manipulate the turntable ground and this eliminated the RF.

Here's something more puzzling. When I re-plugged my turntable into the Rogue 99 tube phono stage, I noticed that the RF disappeared when I touched the pre amp. At first it was my arm on the pre amp with my fingers touching either the turntable ground wire or the turntable leads. I thought great, if only I can find a spare arm to leave on top of the pre amp. The heat would probably make it stink up my living room though. Then I realized if I simply touched the pre amp, the RF disappeared. I tried a separate ground to the pre amp, but this did not prove successful: the RF was back. Yet, when I laid a hand or fingers on the pre amp, the RF disappeared.

If you guys have any more suggestions, I'm game. I feel now, there has to be a simple solution, I just don't know what it is.
Can you tell me exactly what model Grado it is, so I can look up its recommended range of load capacitance. Although many of the Grado's are fairly insensitive to load capacitance, which may be helpful. Also, how long is your phono cable (which adds significant capacitance)? I'll then try to pick out a suitable capacitor.

Your body has capacitance, and that is why touching the preamp affects the RF. When you say you connected it to a separate ground, if you just used a plain wire to do that, the wire's inductance may have made it ineffective at rf frequencies. What you should probably try is a braided ground strap instead, which makes for a much more effective connection at rf frequencies. Or as a temporary experimental arrangement, if possible, try making the ground connection with the shield of a coax cable.

I should have a little time tomorrow to research these parts further.

Regards,
-- Al
Al -- my Grado cartridge is the Reference -- out put 4.0 -- length of the cables are approx. 24" -- they came with the Techno arm for the Michell Gyro Se -- again, I really appreciate your thoughts and suggestions regarding this --

Brian