This circuit was found in an 80's Electronic Design. It amplifies TTL fast signals for a coaxial cable. TTL is from the S (Schottky) line and transistors are types of the time.
In this circuit, the relay remains closed by activating a lamp, for a time that depends on the...
The integrated circuit and configuration are uncommon. However, the sound quality is good. The...
This circuit is like the previous one except that it can be triggered electronically. The circuit is...