Found in American documentation, this circuit for modulated infrared signals can be tuned to a certain frequency. The photodiode can be of any type.
The integrated circuit used in this application is uncommon today. However, the basic...
Found in old documentation, this circuit is intended for low level amplitude modulation with low...
This inverter amplifier is from a 1992 publication. NPN transistors can be BC548 and PNP BC558....