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How I first discovered crystal radio

I was about seven or eight years old, I guess. My grandfather (on my mother's side) had learned to build crystal and valve radios in order to scrape a living in the 1920s, but he had never discussed it with me. My father had been a wireless operator on board ship during WWII, but he never understood how they worked and never really discussed anything to do with the war if he could avoid it. Instead, my introduction to crystal radio came from a Mr Hunwicks, father of Andrew Hunwicks, my best friend at primary school. I think that Andrew's father was some kind of engineer, and there was always some gadget to play with whenever I went round to Andrew's house to play - a hand-cranked dynamo, a hand-cranked 9.5mm movie projector, an old reel-to-reel tape recorder. On one memorable Saturday afternoon I was dragged upstairs to the spare room by Andrew to see the latest marvel - crystal radio.

I ought to point out that I had always had a fascination for things electronic, as far back as I could remember. When I was a toddler, I used to play with my friend Terry with a box of vacuum valves probably given to me by my grandfather. We used to play with them on the stone floor of my father's study and our playroom, standing them up like soldiers, in order of height, or alternating. Curiously, they never ever fell over, smashed, or seriously lacerated me. Naturally, nowadays they would, and my parents would be jailed just for exposing me to such risk. But I digress.

Anyhow, Andrew's father had salvaged an OA81 diode from somewhere and had wound a coil - 45 turns on a toilet roll, I recall as though it were yesterday - which together with aerial, earth and a pair of wartime vintage headphones picked up our favourite local pirate radio station, Radio Caroline. No tuning, just a self-resonant coil for about 208 metres. He explained to me how it worked and showed me how the actual components related to a sketched circuit diagram. In the meantime, Andrew had got bored and gone off to play with his model aircraft - he was a big fan of 'Airfix' kits. When I mentioned that my brother also had a pair of 2000-ohm headphones, Mr Hunwicks asked me if I thought I could rig up an aerial and earth. I knew that I could, because my older brother Martin had a 'Tektronix' radio engineer kit which had all these things in it.

At the end of the day, I was taken home clutching a brown paper bag containing the coil, the OA81 diode and with the circuit diagram drawn on the bag. Immediately I got home, I set about rebuilding the radio. With my parents, brother and sister all watching, I put the components together as I had been shown, connected the headphones, and... it worked! Just like it had at Andrew's house! Well, my family passed the headphones round and were duly impressed by this engineering feat. At that point, my brother, thirteen years my senior, picked up the radio engineer kit box and handed it to me, saying, "Here you are, I think you'd better have this now." Over the following Summer, I built various diode and transistor radio circuits and even, in ignorance, illegal morse and telephony MW radio transmitters. Would that any of these components still existed! Eventually, I wore them all out, and the OA81 was recycled in so many circuits that one day, one of the wires broke off. Sigh.

A couple of years later, the Tektronix set was replaced with a Philips (appropriate) Electronic Engineer kit, which took me a stage further in my hobby. But that's another story.