Hi John,
Yes I did varnish them because that was what the rather ancient "Boy's
Book Of something or other....." instructed ! A lot of experiments seemed to
involve shellac which, at that age, I thought had some special electrical
properties I did learn later that it was probably a waste of time because I
then discovered a wonderful little firm called REPANCO who could sell me some
beautifully wound coils that used something called "Litz" wire and put most
of my efforts to wind the "ultimate crystal set coil" to shame!
My first "amplifier" was constructed by replacing the steel diaphragm
of a headphone earpiece with a "Golden Syrup" can (empty of course). I later
discovered that such an arrangement could also produce a very selective CW
filter - style and size of can being carefully selected. Pity beer cans are made
from aluminium and have concave bottoms! Rather limits their contribution
to "home brew" :))
Happy days
73 de Pat
G4GVW es gd dx
Qth near Felixstowe,
UK
