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theskyfox
20-09-2014, 02:21 PM
Hi Guys,

More for interest than anything else as this is obviously a physics phenomenon! I was driving home late last night in the middle of a heavy storm. I had the radio tuned to a DAB station and noticed that every time there was a lightning strike near the car, the radio (sound - not display) would cut out and not come back until about 10 seconds after. I can only assume that there is some sort of EMP/RF interference at the moment of a lightning strike that causes it. There was no effect when I switched from radio to media. Any else experienced anything odd like this before?

-Andrew

rafletcher
20-09-2014, 02:45 PM
Any electrical discharge ("spark") is accompanied by a radio emission, hence the usual crackles you get on FM radio with lightening about.

allanmb
22-09-2014, 09:10 AM
My Sky signal also goes down for a few seconds after a lightning strike

M1tchy
22-09-2014, 01:36 PM
Yeah it's standard behaviour, lightning gives off a big RF signal which will interfere will comms. You should switch off RF receiving equipment during a lightning storm as the Lightning can piggyback onto an RF transmission and can make your car / home more of a target.

theskyfox
22-09-2014, 04:15 PM
I've heard of RF equipment being blown by a direct strike on the antenna (understandably) but "piggyback onto an RF transmission"...can you give a source for that please? I'd like to know more about it if it is true.

-Andrew

M1tchy
23-09-2014, 11:29 AM
https://www.army.mod.uk/rolefinder/role/53/electronic-warfare-operator/

fat controller
23-09-2014, 10:25 PM
As I understand it, any radio signal be it any on AM/FM or DAB is essentially produced by a modulated 'spark' - as lightening is a big spark (with a capital F), that explains why it knackers any signal coming into your radio

M1tchy
23-09-2014, 10:50 PM
Pretty much yes. I can be really boring as what I don't know about comms and intercepting / disrupting comms isn't worth knowing.

theskyfox
24-09-2014, 09:31 AM
Thanks for the replies. Thats pretty cool that you are an EW Operator. I was asking for interest more than anything else - I always like to know the details of things, which is why I was asking. E.g. I was reading about FM Capture Effect yesterday which is basically what I was experiencing on the radio.

-Andrew

M1tchy
24-09-2014, 09:48 AM
Yeah its a brilliant job, I love it.