This 4-stage circuit has a voltage gain of 10 and negative feedback. The circuit was found in an old MIT publication.
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...