Camera Timer Unit
Technical details

The Radar Camera Timer unit, was powered from the mains and triggered by a pair of contacts in the radar (north marker)
It was provided with a lock-switch to select either 36v or 24v output to a Siemens or Robot camera respectively.
It simply used relays operated by a Crouzet brand 240vac synchronous interval timer. This module was supplied in one of three timings: 0.5 - 30 min, 0.5 - 13 min, 2.5 - 65 min (1)

References
(1) Radar Camera Timer Unit Handbook - EH150