The figure shows how to use the LM3914 Bargraph with an external reference voltage source. The reference cannot be greater than the supply voltage.
This circuit can switch signals in the 3.5 to 30 MHz band. We found it in a QST magazine from the...
We found this circuit in an English documentation from 1995. The components used are common...
This is a field strength meter found in an 80's Hands On. The circuit operates at frequencies up to 500...