This circuit is from a Popular Electronics from the 90s, consisting of a repeater relay for remote control of TV, which today can be done by Wi-Fi or other simpler resources.
This circuit is from a 1997 English magazine, but it is very current due to the components it...
This system of sequential LEDs has its speed adjusted in a 1 M ohm potentiometer and this speed...
This is the commercial circuit for the TRF-44 amplifier sold in Japan in the 1960s. The circuit...