This Texas Instruments circuit is from the 80's. However, it can be implemented with modern operating systems. The power supply must be symmetrical.
This Japanese radio receiver is from the 60s. It has 6 transistors and is powered by 4 batteries with...
Published in a PE Hobbyst Handbook of 1991, this sensor uses an integrated circuit that is unusual...
This circuit was found in a 1969 EEE. The circuit uses transistors from the era that can be...