This transistor class B 5 W amplifier was found in a 1969 Mullard documentation. The transistors are from that time, and modern equivalents may eventually be used.
We found this circuit in a 1967 Electronics World. The circuit can be designed to control other...
The presented circuit monitors a line indicating if it is busy if there is an extension. The...
This circuit is from old documentation. The operational amplifier is uncommon nowadays. The...