The figure shows how to implement an alarm buzzer in an LM3914 to warn about crossing the scale limit. The circuit can use other types of warning.
This 80's circuit has been winning. It is a 1 000 gain sample and hold circuit and an offset...
The purpose of this 1-transistor amplifier is to allow the use of a milliammeter in an application...
We found this circuit in an old General Electric documentation. In fact, PUTs are not common...