This circuit was obtained from a Philips documentation from 1968. The transistors can be replaced with equivalents, only with care so that the doubles are exchanged for matched pairs.
The operational amplifier used in this circuit is not common today, but it can be implemented with...
This circuit is used to test triacs. It can be connected in series with a resistive load such as...
In the figure we have the configuration of a transistor as a temperature sensor. The circuit is...