This circuit that uses potentiometer tuning, was found in a documentation from the 80's. The integrated circuit used is from that time and is a not common today.
This common emitter amplifier with 43 dB gain was found in the August 1970 issue of Radio...
The diagram below is an application of the Texas Instruments TPS25221 to an ISM controlled power...
In this circuit of a 1968 publication the unijunction may be 2N2646 and the transistor BC548. The...