Found in American documentation from the 90s, this circuit can measure frequencies on a linear scale from 0 to 1 kHz. The components can be changed to measure other ranges.
The existence of field effect transistors at the input of the integrated circuit (operational...
This circuit has a maximum output current of 5 A, and the 2N3055 must have an excellent heat sink....
This circuit is suggested by Motorola and is based on a 1723 voltage regulator. The 2N3055...