The integrated circuit used in this amplifier is uncommon today, since the project is from the 90s. The power is 24 V, and the gain of the circuit is 40dB. The input resistance is 1 M ohms.
In the figure we have a simple amplifier stage for BC547 series transistors. The gain is...
Found in a 1980s American documentation, this circuit can use a SCR and a general-purpose transistor....
This circuit was found in a 1973 publication. The operational ones can be exchanged for...