Phono stage picking up radio signals?


The strangest thing happened this evening. I just hooked up my Whest phono stage and as I was letting it warm up I turned up the volume slightly to check the noise level and noticed a strange noise coming from the speakers. At first I thought it was a ground loop hum or some feedback, but when I put my ear to the speaker I distinctly heard music. I turned up the volume a bit and to my surprise I could hear and identify the song playing, followed shortly after by DJ banter. It was obvious I was picking up a radio station, but I don't have a tuner or any other radio device in the home. Can anyone give me a clue as to what might be going on.
clio09
Neil,

Thanks for the explanation. I was looking at the VH Audio Pulsar ICs and according to Chris Ven Haus in addition to being grounded at one end, the shield is also carrying the ground/return. So if I understand your explanation correctly this would not be the best method as it is not a floating shield.

I'll take a look at some of the other recommendations you have made for cable vendors. Could there be a situation where using floating shield ICs on the phono stage will require using them throughout the system? I'd like to just make this one replacement and be done with it.

Thanks,

Tony
RE VH IC's: If the shield is only connected at one end, then it can't be carrying anything. The term "ground return" is sometimes used to mean the negative signal conductor.

You can mix shielded and unshielded in the same system if you want to.

I still advise you to try some inexpensive cables first, just to make sure that it really is the unshielded Nordost that is causing the problem. Cheap Monster, Audioquest, Straightwire, or MIT should do the trick.
Neil, great explanation of "shotgun" topology, and the purpose of the "arrowhead". Most people I know think the arrowhead indicates the directionality of interconnects caused by the grainular structure of the conductor. You have cleared it up.
Zargon, thank you. There are some cable manufacturers who, especially in their speaker cables (which aren't ever "ground shielded",) orient their arrow direction based on "wire draw." Which simply means the direction the wire was pulled through the dies during manufacture. Supposedly, the orientation of the metal crystals as a result of the drawing process makes it easier for the electrons to flow in one direction than the other.

Others who produce spkr. cables and IC's which are symmetrical as far as orientation goes, often include arrow
indications so that (according to them anyway) you'll be able to orient the cables in the same direction, should you have to remove and re-install them after they've been broken in. Personally, I think it's just a "me too" marketing ploy.
I received an email response from James Henriot. It seems there is a modification for the Whest PS .20 for areas with high RF. The modification is now standard on new models of the phono stage sold in the US and Canada. James Henriot from Whest and Bob Leitz at the Analog Shop, where the unit was purchased, have been tremendously helpful and Bob is very much interested in making me a satisfied customer, even though this unit was technically purchased used. I also appreciate all the responses here on this thread, especially Neil who surmised the problem may actually be in the phono stage itself. I've learned a lot here about the various types of noise that can creep into a system.

I'll need to send the unit off, most likely to Mitch Singerman who services these in CA (close to me at least), but I'll post a follow-up when it gets back to me. I'm also going to wait on the cables until it does come back.