This very low frequency amplifier has a gain of 1,000 and was found in a 1967 documentation. The circuit is suitable for detecting explosions, distant echoes and seismic vibrations.
This photometer was found in an English magazine in 1981 but can still be mounted today with...
In the figure we show how to use a 555 to control an SCR or another type of thyristor. Resistors R1, R2...
The circuit was originally designed to operate with MSX microcomputers in 1988 but can be used to...