As a kid, reproducing stuff like this got me into EE. That said, making your own insulation sucks bigtime. The other popular technique involved long thin band

As a kid, reproducing stuff like this got me into EE. That said, making your own insulation sucks bigtime. The other popular technique involved long thin bands of silk, probably not a luxary they had. If you want to try something on a smaller scale, this can be constructed in an hour or two: http://bizarrelabs.com/foxhole.htm http://bizarrelabs.com/foxhole.htm POW radio, but made for AM. Much simpler than shortwave.