This 1 to 40 MHz amplifier is from a 1969 Motorola documentation. The components are of the time but admit modern equivalents.
This voltage-controlled oscillator or VCO was found in a Radio Electronics magazine from July...
This signal follower, from a publication from the 1970s, uses old germanium transistors such as...
This watch uses a liquid crystal display. The circuit is from the 80s and the module used is...