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.
Two identical transformers can be used as a single improvised isolation transformer. The maximum...
This transmitter can send its signals from several kilometers away, depending only on the antenna...
This circuit was found in Radio Electronics magazine from January 1959. The power transistor must...