This unit was developed in 1970, out of the desire to have more accurate results from windflights on the WF3 radar and the experience gained from the printout system of the WF44 radar with its selectable time intervals.
The addition of the Automatic Freeze Timer to the WF3, stopped the Angle and Range Nixie tube displays from continuously updating for a few seconds a selected time interval. This ensured that the radar readings taken by the duty observer were timed accurately.
The Timer was mounted on the side of the console and provided, by push button selector switches, the choice of 0.5, 1 or 2 minute interval selection. A 'Sonalert' tone generator would sound for the five seconds before the selected time interval. (Click on the picture to hear the sound) Then the displays would be held frozen for a short period so the observer could copy the readings from the displays for calculation using the slide rule.
It is believed these were fitted to many radars and the last one was still in use at Wagga Wagga in the late 70's. The Raprint system replaced the Timer and provided full printout capabilities.