We found this circuit in an old Mullard (Philips) documentation on the 555 and 556 integrated circuit (double 555). The relay must be 12 V with contacts that support the horn current.
The circuit is suggested by National Semiconductor in its 1994 Linear Applications Handbook. The...
Found in a 1969 Electronics World, this circuit is intended for amplifying analog cable TV...
Found in an Electronic Design from the 90s, this circuit uses a component of the time, difficult...