Memory Recorder (CB6789E)

This Harris circuit from the 90's is intended for recording old EPROM memories. The circuit uses components of the time.

Full wave slave control (CB8156E)
Using SCRs, this circuit from a 1967 General Electric manual allows full wave load control with SCRs....
Sound Strength Meter (CB12930E)
This interesting circuit from a publication from the 1970s, measures the intensity of the sound...
Simple Transistor Tester (CB19460E)
This simple NPN and PNP transistor tester configuration can use the low current range of a common...