I had acquired two 30cm diameter. circles of blue plastic (the off-cuts from a Mobile Service Station sign) and thought they could form the basis for a crystal set that looked like a pot of colorful flowers?
Believing that the larger the coils the better the Q would be I decided to use the two 30cm diameter. Coils in a band-pass circuit, the amount of coupling between the two coils being adjusted by altering the distance between the two and the antenna being connected to a separate coil wound below the first tuned circuit.

L1 20 turns of colourful hook-up wire with antenna coupling coil of 3 turns of wire tapped each turn on the inside of L1.
L2 20 turns of different colour hook-up wire with detector tap at 15 turns. The 2 gang tuning capacitor had trimmers attached, which were adjusted for tracking at the HF end of the band.
The finished Crystal Set did not look much like a pot of flowers but definitely unusual!!

2nd Prize - Rex Newsome

(The coils is wound with fencing barb wire and mounted on a dunny seat)

3rd Prize - Roland Clark

(Yes there was whiskey in the bottle inside the coil former)

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