Suggested by Amperex in 1968, this circuit is intended for hearing aids. The integrated circuit used, a TAA370 is not common today.
Found in American documentation this circuit uses transistors of the time. The circuit can be made...
The TAA300 integrated circuit is not common today. In fact, the circuit shown is from a Dutch...
This circuit was found in a 1980s documentation. Q1 and Q2 can be BC548 and SCR a TIC106. The...