strange noises on the AM Band in UK

I was listening to Radio 5 Live on 909AM in the Medium Wave this morning at around 6.45am and again this evening at around 5.30pm. On each occasion cutting into the reception was a strange high pitched signal that appeared to repeat itself every few seconds.

I am familiar with the Number Stations broadcasts, that can occur in the Short Wave Frequency and this did seem similar to some of the recorded sounds that I have heard, although there was no voice transmission, just this repeating high pitched 'morse' like signal of several seconds duration.

I am in Essex in the UK and wonder did anyone else catch this - and if anyone has any ideas as to what I actually heard. Whilst reception on the Medium Waveband can be a 'variable feast' particularly in the evening - I have never heard anything like this before.

im just guessing here but maybe its somebody sending out a signal in preparation for a pirate radio broadcast. i know there
still are pirate broadcasters out there.

it might also be some sort of engineer's test signal, but as i said, im just guessing what it might have been.

RDX... It's so hard to know where the interference may have come from. The signal could very well have been a harmonic of something entirely unrelated to the MW band. When radio frequencies interact they can produce 4 different signals. One at each of the original signals and also one each of the sum and difference of the two signals. Faulty raio equipment can do this as can porrly built hobby stuff.

I have just been listening to that waveband again 909am - Arsenal v Real Madrid, anyway, the signal is back, but each one is succeeded by what I can only describe as the sound of waves breaking on a seashore.

This gets curiouser and curiouser................

Hey, why don't you try to get a recording of it so it will be easier to determine what it is?

I go with jtma508 on this one. But without knowing more specifics, I can't really say I know that for sure.

What time of day was it? The reason I ask this, is because at night due to decreasing ionization of the atmosphere, signals travel farther due to propagation effects.

It may well be that you are picking up a station on 910 khz as well, producing hetrodynes?? just a guess.

I really doubt if there are any 'numbers sations' in the A. M. medium wave band.

Also, are you using your computer, or other electronics in close proximity to the reciever?

Could also be 'local interference', meaning VERY close to the reciever, and not any type of broadcast or communications.

larry994



edit = disregard my question 'what time was it?' I forgot you mentioned it...

[edit on 3/10/2006 by larry994]

Originally posted by larry994
...is because at night due to decreasing ionization of the atmosphere, signals travel farther due to propagation effects.

Now I know why stations can be picked up at night that can't be recieved throughout the day.

Anyway, yeah, get a recording and share; sounds interesting, to say the least.