Found in a Hands On Electronics from the 80's, this circuit activates a relay with alternating touches on the push-button. The relay depends on the supply voltage.
SGS's L78xx is equivalent to the regular 78xx. The circuit was found in the SGS manual of linear...
The basis of this circuit is an LM380 that drives a speaker that emits sound when moisture is...
This simple circuit was found in the Spanish magazine “Todo Electronica”, in an edition of 1996....