Southern TV OB

Paul Marshall has restored this four camera outside broadcast unit, which was one of the first colour units in service with ITV. Built by Southern Television Ltd in 1968 at a cost of £225,000, this vehicle retired in 1995 after several refits. It is now restored to 1968 operational status with four working Marconi Mk VII colour cameras. Paul and Dicky Howett run Golden Age Recreations, hiring out vintage television and film equipment to production companies.

This is a description of the unit published by the Independent Television Authority in 1968 :-

Southern’s colour outside broadcast unit, built by the Company, is equipped with four Marconi Mk VII camerasmounting Rank Taylor Hobson zoom lenses. It is built on a Bedford VAL chassis powered by a 145 BHP six cylinder diesel engine and fitted with power steering, five speed gearbox, two-speed back axle and four braking systems.Fibreglass has been used extensively in the construction of the vehicle body ; 34ft long, 8 ft 2ins wide and 1Oft 1in  high. Besides offering advantages in strength and  lightness, this material is also impervious to corrosion, an im­portant consideration as the unit will often operate in the salty atmosphere of coastal areas.

lnternally the vehicle is divided into three compart­ments; sound, production, and vision control. Each compartment has its own heater/cooler unit to afford precise area-by-area control of temperature.

The sound control system is a Pye 24-channel sound­ mixing desk with fold-back, public address and echo facilities on every channel. Comprehensive communications facilities, reel-to-reel tape-recorder and a cassette-type tape machine are also provided. The Sound compartment is equipped with individual 8in camera picture monitors plus a transmission monitor. One of the camera monitors may also be used for preview purposes. A two-way UHF radio link with floor managers is available.

The vision mixing equipment, manufactured by EMI, is a seven input unit of the A-B mix and cut type and is fitted with Richmond Hill special effects equipment for wipes and inlay requirements. Picture monitoring for production purposes is provided by six Sony 9″ monitors and one Rank Cintel 19″ colour monitor. The vision control compartment is equipped with four Pye 14″ monitors and two Rank Cintel 19″ colour monitors. Additionally, monitoring for sound and vision is provided at the supervisory engineer’s posi­tion by means of a peak programme meter and wave­-form monitor. This control position also contains a six-line, 11-extension PBX for control of the circuits. Both real-time and countdown clocks are provided for the Production Assistant.

On the vision control desk, two operational positions are manned by either two vision control engineers or one vision control engineer and a lighting supervi­sor, depending on programme requirements. Picture matching is carried out by reference to picture monitors and waveform displays show the red, green and blue outputs from the cameras and the fully encoded output. Test facilities include grey scale, sine squared pulse-bar and sawtooth generators. A Pluge unit is provided to permit the accurate setting-up of picture monitors.

Across the rear of the vehicle is the main equipment racking. This houses camera control and power supplies, two Marconi pulse generators with genlock and colour lock facilities, Pye vision distribution amplifiers, video patch panels and mains power control unit. The mains control unit provides metering of voltage, current and frequency of the incoming mains supply and contains overload circuit breakers for all equipment supplies. Three Berco automatic voltage regulators are housed in the near-side skirt of the vehicle. Two of these are operational and the third is a spare, which may be switched into circuit on the mains control unit in the event of failure. At the rear near side of the vehicle, the main termina­tion panel is housed and all sound, vision and talk­ back cables into and out of the unit are connected here. Immediately adjacent to the termination panel is a Clark Engineering pneumatic telescopic mast, which extends 33 ft to carry aerials for the off-air receiver and the UHF talk-back transmitter and receiver.