Classroom AV 3: Cable Terminations [1]

The original edition of this article made reference to solutions that we have decided not to implement at our site. Hence, the revised posting makes only passing commentary on those options, focusing instead on our preferred choices.

In Article 1 I referred to faceplates and connectors for VGA and USB connections. Today it’s time to get into the nitty gritty of these and actually terminating off the different cables that you will have. In our case, these are:

  • VGA cable to the projector
  • USB cable to the smartboard (if used)
  • Speaker connections for the sound system’s wall mounted speakers
  • RCA video connection to the projector.

These cables are brought down the wall, preferably in some kind of ducting. An electrician would be able to supply the ducting from trade brands like Clipsal. Then the various sockets have to be mounted on some kind of panel or enclosure. In our case the new classrooms will have these cables built into the wall. Existing classrooms will have the cables terminating inside a shelving unit that is attached to the wall.

The VGA faceplate (if you choose to use it) is available from several electrical accessory manufacturers. PDL supply the Cat 514VH9/I, but this may be out of production now. A similar product is the HPM 770/1D1PL plate.

First job is to fit the PDL plate for the VGA cable. The enclosure is the right size to mount the plate on the side, rather than the front. This works well with the VGA cable having a ferrite core on the end of it and therefore needing a reasonable amount of space inside the box to be turned through 90 degrees to attach to the plate. Since there is enough room on the plate, I drilled a hole to mount an RCA socket for the video connection.


This picture shows how to modify the VGA moulded plug to fit into a plate. Remove the thumbscrews on either side by pulling all the way back and turning until they come right out. Use a hacksaw to cut off the minimum amount of plug shell on each side to expose the metal plate with its two holes at the connector end of the plug. Then use a couple of threaded nuts through the plate’s mounting holes – see Article 1 for details of what to buy. (I would like to thank my good friends at Breezes Road Baptist Church for this idea)


This photo shows another option using the USB feedthrough on the VGA plate instead of an RCA connector. The feedthrough gives you a USB socket that can be mounted onto a wall plate. The reversible insert has a female B connector one side and a female A connector the other. It is mounted on a standard XLR base and will also fit into panels pre-punched for XLR sockets.


Here we have our chosen option, the RCA video socket mounted side by side with the VGA connector on the latter’s faceplate.


Speaker terminals are mounted onto a blank plate which has been drilled to suit, this needs 6 closely spaced holes.

The next article will show the Activboard mounting frame and the cables connecting to it.