Goodricke-Physics-Hub: Difference between revisions

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This leg of the [[Current Broadcast Network]] carries the video and audio feeds from the [[G/046|studio]] through to the [[Broadcast Hub|central distribution hub]] where it is distributed out to the various destinations on campus. It is now the oldest part of the network, having been in it's current form since the station moved to [[G/046]] in 1994.
This leg of the [[Current Broadcast Network]] carried the video and audio feeds from the [[G/046|studio]] through to the [[Broadcast Hub|central distribution hub]] where it was distributed out to the various destinations on campus.


=== Structure ===
=== Structure ===
The cable route consists of a series of extensions added on at each major upheaval in YSTV's history to allow us to keep broadcasting via the existing infrastructure. It is therefore less than planned.
The cable route consists of a series of extensions added on at each major upheaval in YSTV's history to allow us to keep broadcasting via the existing infrastructure. It is therefore less than planned.
 
[[Image:Goodricke-Physics Cables.jpg|thumb|right| Out of the window]]
Behind the monitor rack in the [[G/046|control room]] is a piece of tag strip screwed to the cable duct, which has three XLR connectors coming off it. These are marked up as Network Audio, Derwent Send and Derwent Return. The last two are basically contribution circuits and re-patched as needed, whilst Network Audio should be fed with the balanced network audio signal. Video is carried on a standard BNC connector plugged in to patch box 6.
Behind the monitor rack in the [[G/046|control room]] is a piece of tag strip screwed to the cable duct, which has three XLR connectors coming off it. These are marked up as Network Audio, Derwent Send and Derwent Return. The last two are basically contribution circuits and re-patched as needed, whilst Network Audio should be fed with the balanced network audio signal. Video is carried on a standard BNC connector plugged in to patch box 6.
 
[[Image:Goodricke-Physics Cables2.jpg|thumb|left| Over the top]]
From the tag strip a 3-pair sheilded cable of the type used for the 1998 network and the 150m unbalanced video cable (originally made for [[Breaker 88]]) go through the window frame by the monitor rack, along the top of the G/045 windows and up over the room of the college nucleus. From here it wends it's way down along the covered walkway past the (old) Dining Hall and the bar to the "bus stop", then turns left past the cash machine towards the Physics and Electronics building. Just before the doors into this it goes through a hole in the wall of the building to reach the attic room above [[P/X/002]].
From the tag strip a 3-pair sheilded cable of the type used for the 1998 network and the 150m unbalanced video cable (originally made for [[Breaker 88]]) go through the window frame by the monitor rack, along the top of the G/045 windows and up over the room of the college nucleus. From here it wends it's way down along the covered walkway past the (old) Dining Hall and the bar to the "bus stop", then turns left past the cash machine towards the Physics and Electronics building. Just before the doors into this it goes through holes in the wall of the building to reach the attic room above [[P/X/002]]. There are in fact two separate holes. One above the walkway takes the audio cable and the coax return feed cables, and the other about 2 feet from the floor takes the network video cable, which has wondered off the side of the walkway with a cable tie round the walkway leg to keep it there. This cable then goes up the wall of P/X/002 and then across the ceiling to reach the attic.
 
[[Image:PX002 hole in wall.jpg|thumb|right|The hole in the wall]]
Above P/X/002 there is a wall box with a white plate on it carrying two BNC connectors and four 1/4" jack sockets (someone in York - please take a photo and add it here). These are the ends of the old Rediffusion local contribution cables to [[P/S/016]]. Originally these would have taken individual camera feeds back to the studio and AV rack in P/S/016, but now they act as a pair of audio and video tie lines. The unbalanced video from Goodricke is plugged into the video lead (possibly via a video DA if we want to send video down to [[Physics Concourse|the concourse]] as well). The audio cable splits to three balanced jack connectors (with a common screen), one of which has the network audio on it. How these are plugged in will obviously change the function of the circuits from here onwards, however both sides are labelled, and this shouldn't need changing.
Above P/X/002 in the attic there is a wall box with a white plate on it carrying two BNC connectors and four 1/4" jack sockets (someone in York - please take a photo and add it here). These are the ends of the old Rediffusion local contribution cables to [[P/S/016]]. Originally these would have taken individual camera feeds back to the studio and AV rack in P/S/016, but now they act as a pair of audio and video tie lines. The unbalanced video from Goodricke is plugged into the video lead (possibly via a video DA if we want to send video down to [[Physics Concourse|the concourse]] as well). The audio cable splits to three balanced jack connectors (with a common screen), one of which has the network audio on it. How these are plugged in will obviously change the function of the circuits from here onwards, however both sides are labelled, and this shouldn't need changing.


The video cable on this section, like most of the other local contribution cables, is a Belden braided foil screened type rather than standard RG59. This gives good shielding and so picture quality, but is very difficult to put a standard crimp connector onto successfully! The braid ends are also sharp, which can make the process painful. The audio cables are unshielded, with two grey and two blue cores in each black outer sheath. The 4 jack connectors wire up all 4 pairs (treating the two blue as a pair and so on) in two cables, without regard to phasing. If anyone ever tries stereo, beware! There is no screen connection to the jacks as the cables are unshielded.
The video cable on this section, like most of the other local contribution cables, is a Belden braided foil screened type rather than standard RG59. This gives good shielding and so picture quality, but is very difficult to put a standard crimp connector onto successfully! The braid ends are also sharp, which can make the process painful. The audio cables are unshielded, with two grey and two blue cores in each black outer sheath. The 4 jack connectors wire up all 4 pairs (treating the two blue as a pair and so on) in two cables, without regard to phasing. If anyone ever tries stereo, beware! There is no screen connection to the jacks as the cables are unshielded.
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=== Core Colours ===
=== Core Colours ===
This reflects the wiring in place as of 2006. As all the joints are soldered or terminal blocked, it's unlikely to change, although the patching of the connectors may well do so.
This reflects the {{unsure | audio?}} wiring in place as of 2006. As all the joints are soldered or terminal blocked, it's unlikely to change, although the patching of the connectors may well do so.


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The return feed video cable is the one that comes down from above with the audio in PX003, not the one that comes up through the floor (which is net video). This has changed, so old documentation may list them the other way round. Both go to the control room anyway.
=== Demise ===
In 2011, the long-awaited construction of a new SU building on the site of the old dining room and bar resulted in the removal of a section of covered walkway connecting Physics and the now-James College building. The cabling running through this section was cut, severing the connection from G/046 to the rest of the network, and was eventually left coiled on the roof of the new building upon it's completion in June 2012. No attempt was made to reconnect the lines as the network was by then rarely used, with IP distribution becoming the norm. Cabling remains on the roof to this day.
 
In September 2016, the line coming into G/046 were cut in an effort to tidy up the control room cabling. The exterior cabling is still present.