This very complex circuit in terms of the number of transistors was found in Radio Electronics from March 1966. The circuit is for low impedance headphones. The transistors are from the time.
This 4-digit counter, using CMOS technology, was found in a 1997 documentation. The circuit is...
This circuit activates a relay that has a lamp as a load. The circuit is from a Radio Electronics from...
This circuit can measure frequencies up to just over 1 MHz and uses CMOS technology. The circuit is...