The BBC's Top Gear motoring programme has just shown something curious. The presenter, Jeremy Clarkson, used his remote key to unlock his car from a distance of 40 metres. When he stood 55 metres away the key didn't work. However, when he held the key against his head it did !

What explains the increase in range created by his holding the key this way? His body seems to have become an amplifier or aerial

It does sound odd. By holding the key fob to his head the orientation of the antenna may be changed. He may also be aiming in more precisely by having his eyes on the same level. The height of the fob at 40M may have been waist high. Lastly refecting waves off the pavement?
Occam's razor may slice off the head as amplifier. It could be tested with a tripod at arm's length.

My own experience with remote door unlocking mechanisms is that it sometimes takes one or two tries. It seems possible that the solenoid valve which does the actual unlatching action, occasionally needs an extra jiggle, depending on temperature, clearances, etc.

Slightly off subject. How can the human body act as a radio signal anplifier?
Many's the Time when I've improved reception on my portable TV just by holding the telescopic aerial .Damp palms does not improve things a jot! .Old wives tale!

PS 40 Metres range ? I want one of those. Most are good for 25 yards /30 metres at best! 10/15 metres is their Normal range!

quote:

Originally posted by bedstor:

Many's the Time when I've improved reception on my portable TV just by holding the telescopic aerial .

Yes, that certainly works. This transmitter effect may be related in some way.

Jeremy Clarkson is 6 feet 5 so a transmitter at his head height ought to have good range

When he demonstrated the effect, he held the key away from him at head height and then held it against his head. He was standing in a large open space in which the target car was the only vehicle at the time.