Found in a Hands On Electronics from the 90s, this circuit can be easily assembled today, as the FET can be equivalent and the operational is general-purpose.
This circuit was found in European documentation from the 1980s. The unijunction may be 2N2646 and the...
The figure shows how to obtain a higher output current for an operational amplifier. With the...
We found this circuit in a publication about operational in the 90s. The circuit is based on the...