At your risk. Take safety precautions. Any voltage or current can be dangerous.
A simple,radio can be made by about 60? tourne of thin insulated wire wound to a toilet paper cardboard form.
Then connecting it in parallel to 2 aluminium foils separated by larger size A4 paper.
Radio AM stations can be turned by moving one of the foils relative to the other as this crates a variable capacitor.
Capacitor in parallel with inductor creates an electrical reasonance ciruit.
One of the plates is connected to ground.
The other plate is connected to a long antenna wire.
It is also connected to the grid of an electron tube.
It had been tried long time ago on the input of a Pleiades electron tube MM cartridge RIAA preamplifier. Sound was very good. Electron tube non linearity or even the grid rectification effect demodulates RF to audio. [Armstrong]. This is like creating a side chain voltage out of the transmition program. This side chain signal is at audio frequencies so we can listen to the music.
Would it also work with the coil be wound in ring (toroidal) shape? Taking advantage of the hum
bucking properties of such shape.
Reference:
Operating features of the Audion - E. H. Armstrong
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