Found in a Popular Electronics from the 90s, this shield is activated by a 20 mA current. The inverter is an Open Collector TTL type. The power is 5 V.
The integrated circuit used in this 80's mixer is the LM301A. However the circuit can be used to...
We found this circuit in a Motorola documentation from 1978. The circuit is based on the LM324...
This old slide projector control circuit was found in an 80s Hands On. The circuit uses modern...