This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply voltage and has a 10 Vpp output. The transistors are of the time, but admit equivalents.
Two inverters, of the 6 available in a Low-power Schottky 74LS04, are used in this anti-ring...
The purpose of this circuit is to alternately activate a two-tone horn with low sound and a horn...
This circuit was obtained in an old French publication from the 80s. The maximum power of the lamp...