Suggested by General Electric in a 1968 documentation this integrated amplifier uses a component of the era, the PA237. The circuit runs on 24 V and excites a 16-ohm speaker.
This infrared emitter (pulsating) can be used with several other alarm and remote-control circuits on...
Signals of up to a few tens of kilohertz can be generated by this circuit found in a European...
This amplifier was found in a technical documentation from the 1970s. The circuit uses 2N2218...