This circuit was found in the February 1997 issue of Electronics Now magazine. The frequencies depend on the crystal and other tuned circuits.
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...