1924 Proc. IRE 12 561 A third requirement relates to monitoring facilities.

1933 Proc. IRE 21 1690 The picture monitor..makes possible the monitoring of the radiated signals.

1939 Times 2 Nov. 5/3 Monitoring consists of listening to and recording information contained in programmes broadcast by other countries.

1961 Lancet 22 July 187/2 Continuous monitoring of the atrial pressure would provide early warning of a dangerous rise.

1997 M. Collin & J. Godfrey Altered State viii. 287 The Campaign's code of conduct included the monitoring of temperature and air quality.

1907 Railroad Gaz. 28 June 937/1 One of the most important duties of a monitoring wire chief is to see that all stations have equal opportunity to establish calls.

1929 Congress. Rec. 25 June 2255/1 A bill..to authorize the purchase by the Secretary of Commerce of a site..for use as a constant frequency monitoring radio station.

1937 Discovery Nov. 330/2 At the side of the studio there is a ‘monitoring’ television receiving set, so that the floor directors and the announcers can see the outgoing programme.

1971 Hi-Fi Sound Feb. 66/1 Systems of this standard are, or can be, of ‘monitoring’ class—the sort of equipment Hi-Fi Sound would use for examining the qualities of new recordings or evaluating new cartridges or other components.

1990 Do It Yourself Apr. 17/1 OnSight is the first video monitoring system developed specifically for non-professional use.

2008 Torture & Impunity Jordan's Prisons (Human Rights Watch) App. 77 The monitoring official described his job as observing, and, in the event of an irregular occurrence, of making a recording of it.