We found this circuit in December 1986, Radio Electronics magazine. It uses 3 inverters and has the frequency determined by the crystal. The power supply is 5 V.
This thermostat was found in a 1997 publication. It can be powered by 6 V with the use of a...
This switched-mode circuit was found in the April 1976 issue of Radio Electronics magazine. The...
This circuit was obtained from an old American publication. Transistors are germanium types of the...