Greetings to everyone.
I personally observed this strange phenomenon more that 30 years ago. On one occasion the wire of the coil was burned, the insulation charred but I still could not figure out how or why it has happened to this very day.
I was in high school then and was playing with crystal sets as a hobby. I made my own coil for the LC tank circuit using AWG#30 enamelled copper wire wound onto a size "D" battery (single cell) as a coil form, plus paper insulation. It was a single layer coil about 1.5" long. I slid the coil off the battery after I had wound it.
For an aerial antenna I used the same AWG#30 wire and suspended it at several points using nails through plastic bushings (insulator). A single wire strand ran the entire perimeter of the roof which has a rectangular outline roughly 40-ft x 50-ft, approximately 12-ft above the ground. Lead-in wire was the same single strand AWG#30 going through a window to the crystal set, basically no transmission line. I was in the habit of disconnecting this aerial from the crystal set when not in use.
Earth ground was provided by a metal pipe in the adjacent bathroom.
The plans called for an air-core coil but as I was tuning the unit I found out that I could only receive AM signals if I kept the battery within the coil and so the battery stayed there. The battery was the cheapest available so I presume it is of the carbon-zinc variety. Putting the battery within the coil apparently altered the coil's inductance but I don't know how much or in which direction. But it did work with the battery in the coil so I left it there.
One night there was a thunderstorm and the following morning I reconnected the aerial antenna to the crystal set. Upon connecting the antenna, the coil started to smoke then turned cherry red color then fell off the battery's side forming a heap at the base of the battery. The insulation was charred. Lead-in wire from the aerial was NOT burned, aerial was not burned. Tuning capacitor (cheap plastic unit) was not burned. It was only the coil that was burned. The crystal set did not work any more (understandably) so I left it that way for some time. The entire event lasted for about 3 secs.
Few weeks later I constructed another coil identical to the first one and the crystal set functioned normally as before indicating that no other components were damaged except the coil.
I have kept this event in the back of my head but have not found a plausible explanation to this very day. (I spent the past 20 years of my life in a semiconductor factory doing design & development work for electrical testing of ICs in a production environment.)
I would like to somehow understand what went on with that circuit and this explantation come to mind: The aerial was acting like a capacitor and the thunderstorm had imparted a substantial charge to the aerial. This charge went through the coil and finally to ground. What I don't get is the huge amount of power that was discharged through the coil, coming from a the small-capacitance (?) single-strand aerial antenna, and the event lasted for about 3 secs instead of just milli-seconds. I also did not feel any electric shock even though the enamelled wire offered little insulation, perhaps <200v.
If this is an actual manifestation of radiant energy then I would like to explore it some more. Any plausible explanation would be welcome.
I personally observed this strange phenomenon more that 30 years ago. On one occasion the wire of the coil was burned, the insulation charred but I still could not figure out how or why it has happened to this very day.
I was in high school then and was playing with crystal sets as a hobby. I made my own coil for the LC tank circuit using AWG#30 enamelled copper wire wound onto a size "D" battery (single cell) as a coil form, plus paper insulation. It was a single layer coil about 1.5" long. I slid the coil off the battery after I had wound it.
For an aerial antenna I used the same AWG#30 wire and suspended it at several points using nails through plastic bushings (insulator). A single wire strand ran the entire perimeter of the roof which has a rectangular outline roughly 40-ft x 50-ft, approximately 12-ft above the ground. Lead-in wire was the same single strand AWG#30 going through a window to the crystal set, basically no transmission line. I was in the habit of disconnecting this aerial from the crystal set when not in use.
Earth ground was provided by a metal pipe in the adjacent bathroom.
The plans called for an air-core coil but as I was tuning the unit I found out that I could only receive AM signals if I kept the battery within the coil and so the battery stayed there. The battery was the cheapest available so I presume it is of the carbon-zinc variety. Putting the battery within the coil apparently altered the coil's inductance but I don't know how much or in which direction. But it did work with the battery in the coil so I left it there.
One night there was a thunderstorm and the following morning I reconnected the aerial antenna to the crystal set. Upon connecting the antenna, the coil started to smoke then turned cherry red color then fell off the battery's side forming a heap at the base of the battery. The insulation was charred. Lead-in wire from the aerial was NOT burned, aerial was not burned. Tuning capacitor (cheap plastic unit) was not burned. It was only the coil that was burned. The crystal set did not work any more (understandably) so I left it that way for some time. The entire event lasted for about 3 secs.
Few weeks later I constructed another coil identical to the first one and the crystal set functioned normally as before indicating that no other components were damaged except the coil.
I have kept this event in the back of my head but have not found a plausible explanation to this very day. (I spent the past 20 years of my life in a semiconductor factory doing design & development work for electrical testing of ICs in a production environment.)
I would like to somehow understand what went on with that circuit and this explantation come to mind: The aerial was acting like a capacitor and the thunderstorm had imparted a substantial charge to the aerial. This charge went through the coil and finally to ground. What I don't get is the huge amount of power that was discharged through the coil, coming from a the small-capacitance (?) single-strand aerial antenna, and the event lasted for about 3 secs instead of just milli-seconds. I also did not feel any electric shock even though the enamelled wire offered little insulation, perhaps <200v.
If this is an actual manifestation of radiant energy then I would like to explore it some more. Any plausible explanation would be welcome.
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