We found this circuit in a 1987 documentation. It is a multi-tester with neon lamp and LEDs operating with both low continuous voltage and high alternating voltage.
This circuit was found in Popular Electronics from 1993. The 1458 consists of a double 555. The...
In this application we use an additional input circuit to enable the logic command with keys,...
This configuration was found in an old American documentation from the 80's. The circuit admits more...