This is a typical circuit of a PROM programmer from the 70s. It appeared in the magazine Radio Electronics in 1979. Note that the programming was done manually byte by byte using switches.
This useful inductance bridge was found in a Radio Electronics from September 1963. The...
This circuit uses a 7-segment display to indicate the logic level of a test circuit. The power...
Powered by voltages from 6 to 12 V, this circuit from a Popular Electronics from the 90s,...