"Frank is all homebrew. His receiver is unshielded outside, but built
around a central square of aluminum that houses a Velvet Vernier dial thru
the front panel and some tubes I did not recognize jutting horizontally on
both sides of the box where coils also plug in. The transmitter is a multi-stage affair on a piece of particle board. The tubes are vertical
here, and the bench was littered with brown Hammarlund coils labeled 5, 10,
20, and 80." https://soldersmoke.blogspot.com/2021/07/summer-reading-for-homebrewers-frank.html https://qsl.net/ve7sl/jones%20oscillator.html