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From memory, one of the crystal sets we built, the only manufactured components were some copper wire and the headphones. Tuning was inductive, and the detector was a bit of fine wire contacting a small fragment of galena. It did not work well.
Best one used a manufactured coil former for the coil, a tuning variable capacitor, a bakelite panel, a proper reduction dial for tuning, and a proper holder for the galena. (later replaced at great expense by a germanium point contact diode)
Most parts were scrounged. Soldered joints improved when we saved up and bought a 4oz iron (heated on the stove) and some resin cored wire solder to replace Dad's 2lb iron and stick of solder used for guttering.
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My experience with crystal radio was disappointingly unfulfilling.
Surreptitiously running the aerial through my bedroom window to connect with the garden tap, so I could listen to my own reciever after bedtime, the only civilized (term used loosely) sound was that of Caldwell and Holt, and their cronies, droning on and on and on. To a 9~10 year old boy, that becomes very dull, very quickly.
Fiddling with the tiny frequency dial, the only other sound I could pickup was that of a twin prop aircraft. I listened intently, for what seemed like hours, just waiting for the pilot to say something, anything!
In hindsight, why on earth would my perceived DC 3 be circling my modest weatherboard house in Redcliffe?
It wasn't until many years later, I found out I'd been riveted to static. [bigsad][bigrolf]
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Hello All,
I found this extract of a Wikipedia article about crystal radios really interesting in regards to people making the radios with what things they had on hand while they were in restrictive conditions. Okay - yes I am a researcher and Wikipedia does not have the greatest reputation for reliability or integrity... Anyway normal stuff ... accessed 20th September 2023 from Crystal radio - Wikipedia ...
When Allied troops were halted near Anzio, Italy during the spring of 1944, powered personal radio receivers were strictly prohibited as the Germans had equipment that could detect the local oscillator signal of superheterodyne receivers. Crystal sets lack power driven local oscillators, hence they could not be detected. Some resourceful soldiers constructed "crystal" sets from discarded materials to listen to news and music. One type used a blue steel razor blade and a pencil lead for a detector. The lead point touching the semiconducting oxide coating (magnetite) on the blade formed a crude point-contact diode. By carefully adjusting the pencil lead on the surface of the blade, they could find spots capable of rectification. The sets were dubbed "foxhole radios" by the popular press, and they became part of the folklore of World War II.
It matches earlier comments about people making their own components for use in crystal radio sets.Kind regards
Lionel
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Hooked my crystal set to the rotary dial of the old telephone. Highlight for me was listening to Lionel Rose against Fighting Harada in 1968. Yes, there were proper radios even then, but it was satisfying listening on the crystal set.
