[drphoto]

Well, this is a new one. The leads from my deck (Rega P3-24) are now picking up a radio station. It's very low level, but it's there. Any way to shield?

thanks

[JakeJ]

A quick and dirty method would be to wrap the entire length in tin foil and solder a length of wire to the foil that will allow you to ground it to the ground post for the phono on your preamp.  Make sure the foil doesn't touch the connector at the tonearm end but can have casual contact with the RCA end that connects to the preamp.  Also solder the wire to the foil before you wrap the cable so you don't damage the insulation.
 
Is your tonearm cable extra long?  You may need to cut the foil into strips and wrap the cable in a spiral ribbon.  I'd start at the tonearm end and as you come to the end of each strip just scotch tape it to the next piece with an inch or so of overlap.
 
This is just an experiment to see if additional shielding will help.  If it does you can either look for a better shielded cable or ugrade the current one by getting some copper braided shield large enough to slip over the cable's exterior and use heat shrink to finish it.  This will, however, make it stiffer.
 
Be sure and let us know how it worked, if it worked.

[drphoto]

Jake, gotta dumb question for ya. Where can one find 'tin' foil, or one that can be soldered? I mean you can't solder aluminum foil.....as far as I know.

The leads on this deck are fixed and look to be about 1M in length.

Weird how this just started. Maybe there's some new high power radio station that just came online.

But, man, am I diggin' the vinyl thing, not only for the sound, but the fun of combing the local record shops, like I did as a kid in the 70's. Just scored a couple of minty Supertramp LPs for $5/ea.

Unfortunately, a number of records I love are simply not available on the big disk.

But....I digress.

[Delta Wave]

Have you tried capping the spare RCA inputs on your preamp?

[Wayner]

And to expound on Delta wave's question, do you have any unshielded cables in your system now? If so, they are an antenna. I'mtalking about stuff  like Kimber Kable or something like that where there is no foil or woven shield in place.

In fact, I'd bare bone the LP playback system with just the speakers, amp(preamp) and TT going. If that kills the station, then start adding other components one at a time to find who is the offender.

Wayner

[Delta Wave]

And to expound on Delta wave's question, do you have any unshielded cables in your system now? If so, they are an antenna. I'mtalking about stuff  like Kimber Kable or something like that where there is no foil or woven shield in place.

In fact, I'd bare bone the LP playback system with just the speakers, amp(preamp) and TT going. If that kills the station, then start adding other components one at a time to find who is the offender.

Wayner

Yeah... that too. 

[drphoto]

Yup, I've got some Reality's in there which I'm pretty sure are unshielded. I'll give it a shot later tonight when I finish my 'work from home' job. (just taking a quick break)

thanks

[95Dyna]

Now, if you could just get your tuner to play some records you could call it even.

[JakeJ]

OK here is a piece of wire soldered to a piece of heavy duty tin foil.  It ain't pretty but it is good electrically for this purpose.  All I did is smear a bit of flux paste on the foil so the solder would be better able to "weld" to the foil.  You could also just strip back about 1 1/2" of wire and wrap it around the foil wrapped cable.  The idea is just to make sure there is good contact between the foil and ground wire.

 

[Wayner]

Electrical solder has a rosin core flux so using another flux is un-necessary. Hopefully no one uses plumbers solder on their electrical stuff, as that flux will eventually eat away stuff (acid core solder = no good) for electrical work.

Wayner 

[drphoto]

Can you solder to aluminum? I was under the impression you couldn't.

Still haven't tried unplugging other source, I'm just bouncing over here while I work at my online job. I take a short break about every half hour to let my wrist recover from all the typing.

[Wayner]

Why are we talking about soldering to aluminum? If you have unshielded RCA interconnects, they have to go or you won't get rid of the problem. Making your own shields is a bad idea. They are not going to work well. Get some decent shielded interconnects and solve your problem. Go to http://www.bluejeanscable.com/

Wayner

[BaMorin]

Well, this is a new one. The leads from my deck (Rega P3-24) are now picking up a radio station. It's very low level, but it's there. Any way to shield?

thanks

The same way guitar pickup pockets are shielded........with copper tape. Run the tape down the cables and attach only the preamp end of the tape to the ground of your pre. 3M sells the stuff.  It doesn't need to be thick. Cheap, easy, and works

[david12]

My kit used to pick up French radio stations and French fishing boats, I live in the UK. I've always said you can'nt trust the French. I tried a number of remedies , including using aluminium foil, with lead shot glued to it as well. Did'nt work of course.
  Different phono leads did'nt work, ultimately a new phono stage did. I switched to the K&k stage and it disappeared, as well as being an excellent phono stage

[felixscerri]

G'day all, I've found ferrite 'clamp on' chokes simply placed over the turntable interconnects very effective at supressing this sort of RF breakthrough and 'detection'.  Is the station transmitting on the AM or FM band?  Regards, Felix.

[pansixt]

With unshielded cable, RF is probably not the only interference you're getting.
I'm with Wayner on this one.
With the affordability and quality of Blue Jeans cables, should be a fairly painless fix.
They will even make them in the color you want. With fast turnaround.
James

[TheChairGuy]

Between line level components and amp/preamp...I nearly always prefer the sound of unshielded interconnects.

But, on TT's with rca jacks or captive leads and there is noise...there is simply nothing better than heavily shielded IC's.  The lack of bleed-thru (AM radio usually, soft or sometimes loud) far trumps the more effortless sound that unshielded leads offer on line level or amplification components.

Get shielded for turntables - always - when you can.

John