Phono Preamp Picking Up Radio Signals


Hello Everyone:

I recently moved into a new house, and was anxious to set up my system again.

AAD 2001 monitor and matching stands
Classe CA-151
Classe CP-35
Bellari VP130 phono preamp
Pro-Ject Xpression III TT

The system ran dead quite in my old house; however, now there is a very audible static and radio stations being picked up by the phono preamp. I am certain it is the phono preamp that is the issue. I can move it around and reduce the interference somewhat, but it is easily audible when nothing is playing and distracting during quiet parts of certain albums. I triple checked the ground to make sure it was attached.

Any thoughts. I really don't need to hear AC/DC in the background of my Fleetwood Mac!

Best regards,

Joe
jmleonard400
I looked at a photo of the Bellari and perhaps if you put the phono pre into a Faraday cage? Also probably need some A/C filtering for the last little bit if quieting.
Get a couple of Ferrite chokes and put them on the power line. (if it has a wall wart PS, put them on the umbilical from the wall wart to the Bellari.
Even an aluminum foil Faraday cage can tell you if it will help. Just use a medium size box and cover it completely with the foil, allow only the smallest holes for the cables. If it works, then you can figure out how to make a cage that allows the heat to escape and still do it's job. I am not certain if a wire screen will do the job. If so Copper screen made into a Faraday cage (box)would be best. But i am not sure if the screen mesh is fine enough to block radio frequencies?
I saw this on there web site, its not much.

http://www.rolls.com/pdf/DS_VP130.pdf

I had the same problem with my ASR, but a jumper setting was all that was required.
Here is one of a number of prior threads that have addressed this kind of problem, in which several approaches are suggested that you may want to try in addition to those suggested above.

In that case, as you will see, the problem was ultimately resolved by connecting a braided ground strap between the chassis of the preamp and power amp and ground on the power conditioner the person was using. That may not be applicable in your situation, but experimenting with a ground strap connected between component chassis and/or ac safety ground (e.g., a screw on a wall outlet or power strip) could conceivably do the trick. It would provide connections that have very low impedance at rf frequencies (ordinary wire does not have low impedance at rf frequencies), hence making the different ground points in the system more "common" at those frequencies.

Regards,
-- Al