The circuit shown in the figure below is from the 1993 Linear Technology Applications. The operational ones used are uncommon and the use of equivalents can be analyzed.
This circuit for automotive use was found in 90s American documentation. It is possible to monitor...
This is the target for the CB18793E infrared firing gun. The circuit can be powered by voltages from 5...
This circuit was found in Popular Electronics from 1969. The circuit uses a small speaker as a...