>> CCBBS crowd.  OOOH radioactive.. danger danger.. :-P
>
>Who or what is/are CCBBS ?

Sorry, Circuit Cellar BBS crowd


>anyway, I like the idea of getting the stars into the picture very
much ;)
>How much for a Geiger tube for weak alpha ? I'm looking for something
that
>gives 10-30 clicks per minute for background. There aren't any on
sale
>here.


For alpha, it's a large area diode, you won't be seeing any stellar
alphas, they can't make it through the soup.  Gamma is what you're
thinking of.. Electronics Goldmine had a small tube for sale (and a
cheap counter kit)  What background rate you see is up for grabs
though.

I suppose an old propane lamp mantle in the box would give it enough
background.


OOOH!  Radioactive Ping-Pong balls!  Just dope each one with a
binary-encoded brew of seven isotopes, and use a differential counter
to tell which rad-bits are on.  128 unique codes possible.
The balls would be cheap, but the detector could be a bit pricey.