Distribution Network

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Background

The Distribution Network was for the first 37 years of YSTV's history the only way to watch our programmes before the availability of content via our website. It mirrors the Contribution Network used to get video from around campus back to YSTV's studios for broadcasting major events around campus.

The original network was installed as the university was being built in the 60's.

Early 90's system ageing

The passing of time had taken its toll on the system. By 1994, various colleges/buildings had been remodelled, leading to removal of the AV racks or cutting of contribution/distribution cables. At the time YSTV moved into G/046, the contribution cable from Goodricke back to the Language Teaching Centre (aka LTC) had suffered a break due to the same building work that had lead to the society's eviction from P/X/002. This lead to the contribution point in P/X/002 being pressed back into service. Cables were trailed over the roof of Goodricke college from the new studio to the physics building. From here it fed back to the AV rack in P/S/016 before being sent on to LTC.

At this time YSTV could be seen in Derwent, Langwith, Alcuin, Central hall, Vanbrugh and Goodricke (due to the proximity of the Goodricke snack bar and JCR to G/046 these were fed at baseband into a standard SCART television). Wentworth distribution had been lost sometime between 1993-94.

Failed televisions were repaired by using parts from any spares that could cannibalised from the spares from the garage in Wentworth, as the were no longer in production. Despite best efforts, picture quality was suffering, colour would turn to black and white and then back or various interference patterns could be seen on the screen.

An attempt was made to convince the University to invest in installing a new system of coaxial cable (for unbalanced base-band video) and balanced audio around the campus, but the carrot of allowing them to use it during the conference season was unappealing, and nothing happened.

During the summer holidays of 1995, Owain Davies visited the station and stumbled across a flyer for video balanced line driver and receiver chips which looked ideally suited as it could send pictures over low cost twisted pair cable, bringing the possibility of a YSTV funded replacement network into reach. Vanbrugh college was used to test out the devices.

Two kilometres of twisted pair

A budget surplus in 1997 left enough money in the society bank account at the end of year to buy a new set of identical ex-rental stereo televisions and two kilometres of cable - enough to rewire all colleges on campus.

During the summer holidays of 1998 newly appointed Network Engineer Rob Sprowson convinced YSTV that it was time to replace the Rediffusion network, to install an entirely new network.

Despite the availability of content online it remains a valuable means of raising the society's profile on campus and generating interest in our output, the status now is basically the 1998 layout minus sections lost to new building works, with some new links installed and a few of the TVs relocated.

IP-Based Distribution

As time went on, and the network slowly degraded, repairs became difficult, and in many cases impossible because most of the routes the cables take have been declared off limits due to asbestos. As a result of this, Simon Harris, the network engineer who didn't have much of a network to be engineer of, proposed making use of the actively maintained campus data network. Seeing as we already had a webstream by this point, it was a simple task to set up a second, higher quality stream specifically for on-campus use by these laptops. The name of the laptops? Drains which, as Simon will explain, is because they are at the end of a stream. As of September 2009, the system has already been used to get YSTV's content to The Courtyard, YUSU's own bar. Drains are now mainly comprised of just Windows XP, running Google Chrome fullscreen.