We found this precision circuit in a manual from the 80's. The operational amplifier is of a common type at the time, and equivalents can be tested. Transistors are general purpose types.
This circuit is from a 1968 Electronic Design. The components are from the era and the operating...
This circuit was found in an Electronic Design from the 90s. The integrated circuit is from that...
This circuit, from a 1988 documentation, activates a relay for a period and has a touch shutdown as...