P169 Replacement

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This article is about a piece of equipment. For more information on what it is for or how to use it, try its documents wiki article.

This was a project initiated by Michael Cullen aiming to replace the old slowly dying P169s with something a little more modern.

The plan was to construct an 8x8 version of the Station Video Mux using the newer equivalent of the Maxim chips acquired using the same method. This is complicated somewhat as the op-amps needed by these maxim chips are only available as surface mount devices.

The circuit would be controlled by an Atmel AVR because Michael Cullen likes these.


Michael Chislett somehow ended up with the project, and couldn't resist adding some awesome features to the list: not only would the matrixes be 8x8, but they could now team up to be 16x8 machines, by linking two units together to create a bussed output, using clever disabling of different chips output lines. They'd also sport shiny blue LCD's, because they make them usable, and were conveniently cheap via a supplier who had no idea of their value! (Mike acquired them for around a fifth of their wholesale value). They would also use Mike's pipe-dream protocol called yvp, (YstvVisionPath) so that they could in future communicate via butchered xml over serial ports to the rest of the vision path, to route things like tally lights... It still remains to be seen whether yvp will catch on.


In 2011, two prototypes were made on veraboard, and surprisingly, after a few hours of tweaks, they worked! and in 16x8 mode too! Shortly after, Mike Submitted them as NaSTA 2010 technical projects, these then went on to win (the only actual 100% win in the last 3 years, i.e. not "highly commended" etc) the NaSTA, as judged by Ex-member and now BBC Tehcnologist, Rowan de Pomerai.


Despite actually being in a box (CPC cardboard style!), and functioning, Mike then destroyed the matrixes, in the hope that one-day, he would get round to making them in a decent case, on PCB's that didn't experience interesting EMC issues. as of the start of the 2011/2012 academic year, the matrixes will be finished, having been given the finishing touches over the summer.


After the final build, the whole project will be open sourced, as various NaSTA stations have shown great interest in the project, and Mike blindly agreeing to do so.


We should probably point out that the matrixes do also support some unusual 'Easter Eggs', having been planted by Mike at the beginning of the project's coding. You are encouraged to find them, but not during or preceding a broadcast! Easter eggs vary in complexity and degree of randomness. In some of the more interesting eggs, the matrixes will dance, flash lights and anything else the YVP mainframe can find, and ask the YVP mainframe to remap the entire vision path and tally system!

Robert Walker rediscovered a nearly completed matrix in the tech room in 2013, having never been finished. With the move to HD, the idea of these became rather obsoleted...