Freeze Alarm (CB14454E)

The circuit of a 1968 publication can be implemented with more modern transistors such as BC548 for NPN and BC558 for PNP.

Transmitter for Thermocouple LM10 (CB14312E)
The components used in this National Semiconductor circuit are not common today, but the...
Mike Gain Increaser (CB17253E)
This 2001 circuit is used with transceivers to increase the gain of a microphone and thus obtain...
2-Transistor Regulator (CB20298E)
In the figure we have the configuration of a variable voltage regulator with two transistors and a...