Seventy years ago this month, the June 1945 issue of Popular Mechanics carried the plans for the two crystal sets shown here. As the article points out, crystal sets can come in two varieties. The simplest set has little selectivity, and is suitable only for tuning in the one strongest station in a given area. For more variety, a more complex set with more selectivity is required. The magazine showed two sets, one in each category.
The simple set had its coil and all of the other parts mounted on a plastic drinking cup. The more selective set contained two variable condensers, both salvaged from old broadcast radios. Complete crystal detectors could be purchased for about 25 cents, or the builder could make one with a piece of galena. Thus, even with wartime parts shortages, most hobbyists would be able to scavenge together the needed parts.
For those wishing to replicate one of these designs today, I have ideas for finding parts on my crystal set parts page.
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Hi,
I liked your Two 1945 crystal sets. COULD YOU SEND ME PLANS FOR THE TWO SETS?
I live in India and my city Chennai has 2 MW stations with 200 kW and 20 kW .
Mohan
Hi, Mohan.
You can just click on the link that says “Popular Mechanics” and it will take you to the original 1945 article with the plans:
https://books.google.com/books?id=Pt8DAAAAMBAJ&pg=PA142#v=onepage&q&f=false
Thank you for sending link for 1945 crystal radio article.
I constructed my first crystal radio in 1967 at the age of 17. It was just a diode and a telephone receiver earphone with 10 meters enamelled copper wire as antenna. I used to touch the ground terminal with my finger and sit in cement floor whenever I listen to local radio programmes. Later I forgot crystal radio and started college eduction, then job, family, children etc etc.. Now I am 67 and developed interest in crystal radio.
The second plan with double coil and double condensers is interesting to me. I will construct it and let you know my experiment with it.
Once again I thank you for sending me the link.
With regards
Mohan
from Chennai, India.