Marconi MkVIII Television Camera Varotal 30 lens open

The black box with a "4" on it is the zoom servo amplifier There is also a smaller amplifier for the iris control.

The focus is mechanical in operation, the lens engaging with a spigot on the camera body.

To the left is the card that fits in the camera electronics bay. This lens just requires some fuses as the amplifiers are in the lens body.