First-Hand:My First Handmade Radio
I atended the NanKai middle school in ChungKing during the last two years of WWII. Our school was a boarding school and we had strict rules, much like in the army training camp, that the lights were out at 9:30 PM and the bugle will wake us up at 5:30 AM every morning. In order to pass time during these long nights, and not to disturb our fellow class mates, I rigged up a simple super-regenerative crystal radio. This radio consisted of a five feet long enamal wire for antenna, a RC tank circuit for channel selection, an earphone and a point contact cupper oxide crystal rectifier ( I bought the crystal from a local herbal medicine store, and the contact was made with a bent needle), There was no battery or any energy sources to this circuit, except the radio energy received from the antenna. I was lucky that there was a radio station with a huge broadcasting antenna located just a mile from our school, so the reception was great and the sound from the ear phone was laud and clear. This radio served me well for many months until my extracurricular activity was discovered by our domitory director. After much begging,I was able to keep my eaphone, which I spent about one month of my allowance to pay for, but my first hand made radio was confiscated.
With this brief introduction to radio, I joined the Chinese Ameature Radio Legue (CARL). As I recall, this organization was affiliated with IRE, the predecessor of IEEE. I still have a CRAL pin which I plan to donate to GHN as an item may be of historical interest.