Radio Frequency Interference Question

Posted by: novelty on 28 July 2003

My apologies, i know this topic has been discussed at length but my search string isn't coming up with a scenario specific to mine..

i have a q fm3/cd3.5/fc2/nait3 in the bedroom and am getting significant radio frequency interference on one speaker..

the problem started last evening when we were bedding down for the night and it kinda freaked out my wife..i disconnected my speakers so we could sleep..does anyone know of a quick fix for this type of thing??

this has not been a problem in the past..initially i thought maybe a neighbor installed/moved/altered some satelite or hifi gear or something??

also, i can't make out the source..i have read here that AM can be the culprit but if i were to guess, it sounds like i am picking up a conversation among members of alqueda operative cell..the language is foreign but i can not make it out..

i am going to talk to a few neighbors tonight to ascertain if they are the cause..In the meantime does anyone have suggestions??

many thanks in advance.

"So what ya gonna do when the novelty has gone.."
Posted on: 28 July 2003 by novelty
quote:
Originally posted by sross:
Sounds like you might be subject to some radio frequency interference from a nearby transmitting ham radio operator. It would explain both the foreign language and the time of day of the interference. You're in the Chicago area so I'd suggest you contact M&M Radio Laboratories on Milwaukee Avenue and let them know you need an inexpensive passband filter to remove RF interference. They'll know exactly what to do.

You can also try making a makeshift toroidal filter by simply making five or six small loops about two inches across in your speaker cables and all of the power cords running to your kit and secure them with a plastic tie. You might be able to eliminate the RF interference without the passband filter.


Thanks i called m&m and they are out of the radio business, underground detection is the business now, no one there could offer useful advice..i will try twisting the mains cables..

thanks again.

"So what ya gonna do when the novelty has gone.."
Posted on: 28 July 2003 by Chris Brandon
Just found this by Paul Darwin.....

"Paul Darwin
Administrator
posted Fri 20 April 01 22:04
RF Interference.

A couple of things that you might like to check that can exacerbate the problem are as follows,
If you have an excess of speaker cable make sure that it is not coiled up as this can act as an aerial , better to figure of eight it to cancel any RF interferrence.Secondly , make sure that signal and mains leads are separated and do not cross each other as this can also in certain circumstances be problematical.
Failing that there can be several external factors which can contribute , over which you have no control".

Also,make sure that ALL your connections are clean (including mains plugs,leads,signal etc etc)

Try a search on this site using "interference"

HTH

Chris
Posted on: 29 July 2003 by Bruce Woodhouse
Mine disappeared when I used a hydra in place of all the mains cables. Not the hydra itself perhaps, but moving mains cableas away from SNAIC/speaker cables probably. Used to drive me potty at times before. Can anyone explain why radio interference is always in portugese?

Bruce
Posted on: 29 July 2003 by novelty
Thanks for the help gentlemen, i will get my cables sorted out accordingly..the kit is sitting on top of an antique claw foot chest..i have the cables running behind and underneath where there is about 6" of clearance above the floor..probably not ideal..i do have my naca5 figure 8ed behind the chest but there is a fair amount..i am afraid to cut it too short..
anyway, will redo the cable setup and problem should be solved..no issues last night btw..

Many thanks for the replies..

"So what ya gonna do when the novelty has gone.."
Posted on: 30 July 2003 by pcm
Not quite, Bruce!
Mine was Radio Bulgaria at night and something American in the day. Naim fitted a filter into the snaxo and there has been no further interference.
pcm