This page contains downloadable PDF files of various accessories for the ham shack.
1) A CPO (Code Practice Oscillator) which uses a 117L7/M7 tube. It was originally designed to be mounted inside an Instructograph code machine.
2) A CPO (Code Practice Oscillator) which uses a 70L7 tube. It was originally designed to be mounted inside a different model of Instructograph code machine.
3) Some home-made tube sockets.