This small AM transmitter was found in a Japanese publication from the 1960s. The coil has 20 + 80 turns of wire 28 to 32 in a tube inside which a ferrite core can be fitted.

This small AM transmitter was found in a Japanese publication from the 1960s. The coil has 20 + 80 turns of wire 28 to 32 in a tube inside which a ferrite core can be fitted.