This circuit was found in a Popular Electronics from the 90s. The transistors are general purpose, and the gain depends on the ratio between R2 and R1.
Suitable for the use with sensors, this circuit from National Semiconductor appears in other...
The circuit presented emulates an OR gate with the LM3900, operational transconductance amplifier....
This circuit has a very high input impedance and a very low output impedance. We found it on a...