This circuit uses a quadruple operational amplifier of the time. The circuit is from the 70s but can be implemented with modern operators that require the use of a symmetrical source.
This variable voltage reference uses a Norton operational amplifier. The voltage is adjusted at...
This 6 transistor TR26 commercial radio was sold in Japan in the 60s. It is a super heterodyne circuit...
n be assembled with BC558 transistors for low power transistors and a BD136 for the output. The...