Stratos UK has supplied and installed fibre-optic cables and connectors as part of the new infrastructure for the BBC Resources HD upgrade project of the largest BBC studio – the 955-square metre TC1 at Television Centre. The first phase of the project was completed in time for the live production of ‘Sports Relief’ at the start of the summer.
After a period of tests and trials, the BBC selected the Stratos HX-1080 series of expanded beam connectors for the SMPTE 311M hybrid FO camera cable links. Connectors, including 62 bulkheads and 18 in-line plugs for patch-panel connections, were all terminated and installed on site. There are 20 SMPTE 311M-compatible camera cable connections around the studio floor, four on the studio gantry and four more in an adjacent production area.
Two further external connects are outside the studio, so cameras can be rigged for use around the famous ‘horseshoe’ at the entrance of the Television Centre.
The installation required adapting cameras to HX-1080 connectivity including 18 Sony HDC1500s and four Sony HDTX-100 triax adapters. In addition, Lemo 3K.93c to HX-1080 adapter cables enables using Lemo-configured camera inventory within the new infrastructure.
Care was taken to make sure the cables would fit-in with studio operation. So, of the 31 floor cables supplied, 26 use ‘fat’ 16mm SMPTE cable from Furukawa, matching the diameter of traditional studio triax and allowing camera pedestal skirts to push the cables aside as they move. The remaining cables use the more usual 9.5mm SMPTE 311M cable.
The Stratos HX-1080 connector is designed for use with SMPTE 311M-compliant hybrid camera cable that includes power and data paths on copper conductors, as well as the two fibre optical paths. The connector includes many features designed to make frequent rigging on OBs and studio floors straightforward and reliable including hermetic seals and hermaphroditic – any to any – plugging.
The use of Stratos’ Expanded Beam (EB) technology for the optical connections means that, unlike the commonly used PC (physical contact) connectors, these do not degrade with re-plugging. With EB, the fibre’s light beam is magnified and collimated by a lens to making it many hundreds times the area of the 9-micron single mode fibre. The large beam means that the otherwise troublesome dirt/pollen particles are too small to obstruct all the light.
Also the lenses are recessed meaning there is no physical contact so no damage or wear to the optical path occurs over repeated re-connections.