This circuit is from Texas Instruments documentation from the 1980s. The operatinal ones are from the era and the power supply must be symmetrical.
This circuit was obtained in a 1978 English magazine. This adjustable stabilized power source...
In the figure we have a modulated siren circuit that excites a loudspeaker with good power. If the...
The purpose of this circuit is to amplify the signal of a phone pickup and to be able to reproduce the...