We have many tube tester circuits in this section. This one came out on a Radio Electronics from 1949 and has a very elaborate configuration with toggle switches.
This 1 A circuit was found in a Philips documentation from 1966. The transistor is of the time,...
This FM transmitter circuit was found in a Japanese publication in 1975. Equivalent transistors can be...
In the figure we have the basic configuration of a 5 V regulator using an operational 741. In this...