We found this circuit in a 1968 General Electric publication. The circuit uses an SCR of the time, but any modern equivalent can be used. The relay must have contacts that support the horn current.
This circuit was found in an American publication from 1969. Transistors are from the time and can be...
We found this circuit in a 1998 documentation. The circuit makes use of CMOS logic and must be...
This 1 transistor circuit is from a Radio Electronics from December 1958… The circuit is battery...