This 18 V x 300 mA power supply was found in a 1969 documentation. The integrated circuit is difficult to obtain today.
This transistorized oscillator, a modification of the Colpitts oscillator, was found in the...
This circuit uses a CA3140, an operational amplifier with FETs in the input stages. Equivalent can be...
This signal injector and tracer (follower) was found in an old American documentation. The...