We go off to the mine to try out what we have - the
exposed light-sensitive diodes from the radio, the laser
pointer and a multitude of different reflectors. It's
deliciously, amazingly cool inside the mine. A blast
of cold air comes racing at you just on opening the
doors. It feels too good to be true in the heat of the
desert! You can't believe it will continue to keep blowing.
It takes AGES, just ages, to work out and to film.
We do find that smaller tubes make the tin foil vibrate
more. That may be good - we may need to maximise the
response. But maybe we just need to use bigger reflectors
- casting a light beam over a distance is harder than
I'd imagined. Using a wider light beam may be necessary
just to be able to see the damn thing to be able to
line it all up. At least we've learned something and
Jonathan's detector worked.
I tried out different options outside the mine - a
bit of mirror stuck on a rubber diaphragm (a bit of
old car tyre) compared with a tube with tin foil stretched
over it. Jonathan tweaked his diodes, I played with
my reflectors, then we set it all up outside - and it
all felt quite promising. It actually worked. Everyone
The challenge now is to make it work over a distance
of more than 15 metres. In fact, Kate now tells us we
have to get a signal across the length of the mine.
Hmmm! Thanks, Kate!