This can be considered a complete laboratory for the repair professional. A full featured signal tracer with 13 tubes. The circuit is from the March 1946 issue of Radio Craft.
Suggested by Mullard in a1969 documentation, this circuit generates the erasure signal for tape...
This low noise microphone preamplifier circuit was found in American documentation from the 90s....
This transmitter for modulated radiation can be used as an optical data shield. The maximum...