This amplifier for hearing aid was found in a 1968 documentation using an integrated of the time. The power is from a battery, the consumption of 1.65 mA and the power of about to 1 mW.
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...