Below: cigarette dispenser in black and blue Perspex. You can tell how old this is as I gave up smoking over 40 years ago! There are two LDRs which are arranged as a potential divider. Waving you hand over the LDRs changes the output of the potential divider which triggers the drum to turn one revolution, dispensing one cigarette from the hopper. You can see the old-style transistors in cans and the chunky resistors.
I almost sold this belt to a minor film star for £25 a long time ago when £25 was £25. (For example, at that time lobster thermidor was £5 at a posh restaurant in Brighton, as I remember.)
Almost sold it…
I’ve never had lobster thermidor but I expect it is very nice - except for the lobster that is.
I used to make and sell these belts and buckles to a shop in Oxford Street. It was quite hard work and I eventually had to get a proper job.
Below, a point contact diode from the crystal set made for my son over twenty years ago. You can just see the zig zag wire which touches the semi conducting germanium crystal producing a rectifying p-n junction. This is fairly close to the cat’s whiskers of the 1920s radios. Below that is the crystal set itself. To work, it needs a long aerial maybe 30 or 40 feet long and a connection to ground.
Variable tuning capacitor (or as we used to call them, “condenser”) with mica dialectric between the plates for compactness.