Radio interferance

[MarkyB]

I notice something interesting about the radio in my Minor last weekend.
During the day it worked fine, but when I switched the headlights on I found that it made various crackles and pops all the time.
I'm trying to remember if it was only when the car was moving, but I think it was all the time the lights were on.
Everything electrical is standard, powered by a dynamo no suppressors fitted anywhere.
Any ideas?

[jimbo1]

I would think it is because of poor connections due to corrosion causing very tiny arcs every now and then and a bit of RF as product.
Try cleaning up as many bullets and spades as you can find and make sure the earthing is really good.
The problem might well be worse when the atmosphere is damp.

[bmcecosse]

When the headlights are on - an extra coil in the voltage Regulator is energised - which throws more volts at the dynamo field - and the dynamo then pumps out more amps! So the noise could come from the Regulator working harder - or the dynamo working harder to make the amps. Add some capacitors - sprinkle around the car - and put one on the feed cable to the wireless.

[jimbo1]

I meant to say check connections on the lighting circuit.
I would have thought the regulator theory would, if it is the cause, produce a less random noise which is not what i think you implied.
it will certainly be cheaper and easier just to check your lighting connectors first.
let us know how you get on.

[MarkyB]

Where can I get cheap capacitors so I can try BMCs shake'n'vac technique ?

I'll have another listen as the sounds might be more specific that "crackles and pops"

[bmcecosse]

Any motoring shop I expect!

[PSL184]

Where can I get cheap capacitors

Maplins or RS Componants