Dressing up as a WW2 soldier who had become a Prisoner of War.
The POWs might have had to eat stale bread...
or raw potatoes...
or grass...
or even rats!
We wound fine wire around a cylinder to create a coil:
When the radio set was finished we used earphones to listen to the broadcast:
Time to decode a message in morse code (played four times slower than it would have been AND we were able to repeat each letter as often as we wanted).
