->  WC> OTOH my Cub Scout Crystal radio had an inductor wound on
->  WC> a Quaker Oats box with a slider for tuning.

->  WC> The capacitor was fixed and made from the genuine tin foil
->  WC> once found on gum wrappers you could peel off the paper backing.

-> I don't buy gum,  don't they use that stuff any more?

I don't buy gum either except for that occassion.

Nope, they don't use solderable tin foil anymore but aluminum foil :-(
I used squares of wax paper for the dielectric and a slider across
the inductor for tuning.
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