electrical interference?? on tv etc.

[andywybers]

Don't know whether this is right place..... When tv is on in kitchen it keeps intermittently getting some sort of interference, the same with my young daughters baby monitor, same with my radio as well. It probably happens every minute or so for about 5 secs. I don't know whether it's electrical or not. It can happen simultaneously or when only one of the above is on at any one time, very annoying. Doesn't happen in any other part of the house with any other appliance.

 

[Graeme]

More or likely your mobile phone. See if it still does it when switched off

 

[breezer]

may be the fridge / fridge freezer, you need to find out what is causing it by a process of ilimination

 

[mapj1]

what does it sound like on the radio,
For example
tone or cacophony of multiple rhythmic tones (electronic interference, computers videos, some water softeners),
50Hz buzz (something mains powered, motor, dimmer switch etc.),
zubb-uddy-zub-zub-zub (GSM phone calling sequence)
Hissing sound, (broadband PLT interference)
Other (can you record it - we may recognise it.)

And does it coincide with the boiler firing, or a phone ringing, or next door's boiler firing , etc. ?
You may be able to track it down with a portable MW radio, the antennas in these are directional, and when the rod presents maximum length to the source the signal is greatest. (often, paradoxically it is easier to search for the null, as then the rod antenna is pointing at the interference source, and triangulate from a number of points.)
Then its a case of working out if the equipment is radiating too much, or your gear is inadequately immune.
best of luck, these can be tedious.

 

[andywybers]

Its a noise of interference like when you are tuning in a tv and its searching for channels. The boiler firing theory sounds credible though because obviously that's on in the evening mainly, when we are watching tv/radio in the kitchen. What, if any is the cure?

 

[Screwi]

could be a local cb'er - look for large vertical ariels in your road.

 

[mapj1]

Firrst trace the source, a portable radio might be useful here - one with a rod aerial will null when the thin (pointy end) of the rod is facing the source (as maximum is broadside to the source..., but null is easier to recognise.). Triangualte from 2 or 3 places to zoom in... beware of chasing reflections.
Once narrowed down , it may need a suppressor (if electrical) or it may be your gear that is insufficiently immune, and requires additional filtering on its cables.
Try and borrow 'the radio amateur's guide to EMC' from your local library... Aimed at radio hams, but a the tracing and fixing interfernce is reasonable read for anyone wanting to brush up the basics..

 

[felix]

The sound is all wrong for a mobile phone. These put out a rapid 'chirping' noise which can even be heard on a TV switched to standby. (Not many people realize that a mobile phone keeps telling the network where it is even if you're not using it.) The repetitive nature would also tend to rule out CB activity.

When I got a sound exactly like the one you describe I traced it to a thermostat on a fan assisted radiator. The thing was cycling on and off (as room stats often do) but not snapping open cleanly. Result - about five seconds of arcing every few minutes which was clearly audible on a TV with a set-top aerial.