Mythbusters

We busted one myth, but have confirmed the other.  The first myth about unlocking your car with a mobile phone would be handy if you locked your keys inside.

The myth says you get someone at home to grab your spare key remote and press the unlock button close to their mobile phone while you hold your phone close to the car so the signal can unlock it.  We tested it on several cars and it doesn't work.

However, she says the other myth about using your head does work.  It has already been shown on the UK Top Gear motoring TV show.

We tested it on several cars and found it adds at least 20m to the effective range of the remote.  Dr Castro says she uses her head "all the time".

"I've tried it on my crappy Corolla and it works," she says.  "The human head acts an antenna because you are basically building a capacitor with the water content inside your head."

Dr Ziri-Castro, who studied telecommunications at Queens Uni in Belfast, says it is safe to use your head as an antenna for a remote key fob.  "It's low frequency so it should be all right," she says.  "If it were a microwave it would be a different matter."