Sample and hold element

Sample and hold element .
This module must be used to discontinuously sample the behaviour of a continuous control on a process. The sampling frequency shall be provided by the generator which will be integrated in the module or by an external signal.
Technical features:
•Power supply: +15 V ; 0 V ; -15 V
•Signal voltage range: -10 V, ..., +10 V
•Sampling frequency:  0,2 .... 20 Hz
It must be mounted on an insulated didactic module, it must show a schematic diagram and 2 mm terminals for the electrical connection; one potentiometer. It must include also a bus for the supply that allows the connection between the panels.