Found in an Electronics Now from the 90s, this circuit appears elsewhere in this section and website. The diodes are for general use and the basic frequency is given by C.
This circuit was designed to power the previous circuits of the wireless sound system, but it can...
This circuit is from the documentation of Radio Shack 1975. It can be mounted with 12 V relays,...
This circuit is suggested by the Optoelectronics Sourcebook by Texas Instruments when AC signals...