RE: WHAT DO YOU THINK ? - 3

Oh well that happens all the time old chap.
Did the Doctor give you some tablets? Did you forget to take them again?

No he just used his Sonic Screwdriver

Mmmm, loose screws and all that. Probably beyond fixin'.

Ralgex and WD40 work wonders.

This one is for Voltman,
I listen to all night radio 5, and last night was driven barmy by some nurd who spent 10 minutes explaining ampitude modulation, what the **** is that.

Amplitude Modulation (AM) is where the strength (Amplitude) of the signal carried by the radio wave is varied (Modulated) according to the strength of the audio frequencies it is carrying. This variation is easily filtered off and converted back to audio and is the signal a crystal set works with.

Frequency Modulation (FM) is where the Frequency of the radio wave is varied (Modulated) according to the strength of the audio frequencies it is carrying. This signal is more complicated to convert to audio.

Better, and more complicated, explanantions abound on t'internet.
VM

Thanks Volty, it all started when some silly so and so rang in and asked why his radio got louder as he was nearer the transmitter.

Have you ever driven past the Droitwhich transmitter?

Last time I went by all I could get on the radio was Radio 2. They transmit a massive signal compared to the rest.
I have this theory that a box of disconnected radio bits would play something if put near that transmitter.
VM

Why do I get police and other emergency services radio signals over my computer speakers when they are nearby?

Phil

Phil,
We used to get them coming through the jukebox at the Beeches.

John

Trust the coppers they will do anything for a free after time drink

Phil

Must have been some sort of tunnel and trap door arrangement.

There is a coil of wire in a loudspeaker that I suppose could become a tuned circuit if there is also a capacitor across the coil for frequency filtering purposes.
As the circuit isn't designed for a receiver it could easily have a very wide band acceptance (low selectivity) and could pickup some very strong local signals.
Your speakers appear either not to be screened or the cables are very long or both.

Or the radio reception is being performed elsewhere in your system and you blame the speakers because that is the only place the audio can emanate from.

The police now use a newish digital technology called TETRA for their transmissions, which whilst it does interfere with some other equipment is unintelligable.
The fire service is still in the clear but is a bit of a grotty signal.
VM

Is it only me, but it seems that only the first 5 or 6 threads are added to each day,and all the rest seem to be added to a list of pages and forgotten.

John

Yes it does seem to be that way, but in general this only means that no one has anything further to add on the topic. One of the problems of being a small forum with a small membership.

Phil