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The Memotech MTX Series

Memotech Photos - Multi-Effect Video Wall


Multi-Effect Video Wall Pictures - courtesy of Mike Rudkin


The MTX computer used for the Video Wall System. You can just make out the Cameron Video Systems logo on the left hand side of the keyboard label, probably just stuck over the original Memotech one.

Most were MTX512 Series 2s, but I think some were also the RS128 model.

Photo of the MTX Video Wall computer internals, showing the main board, a ROM card and a cut-down RS232 interface which lacks the interface components used for the FDX etc. The additional ROMs allowed the system to boot into the Video Wall system without the need for the optional SDX disk drive.
The internals of the Video Wall Controller. 

Each half of this controller has 4 or 5 Frame Memory boards and a Controller board. The controller boards were multi-dropped on the ribbon cable connected to the MTX Centronics interface which is visible next to the silver UHF modulator in the photo above.

The frame buffer box looked very much like an FDX case, it was variously described as the "Black Magic box" or the "DDFS Control Unit".

The Video Wall controller also had a second, smaller, "Black Magic" box, this was a composite video decoder. Its function was to take the composite video signal and split the components into (R)ed, (G)reen, (B)lue and (S)ync - RGBS.

The lower board is the demodulator board, it accepted a composite video input and output RGBS for the Video Wall controller. The large chip in the middle of the board is a ST Microelectronics PAL/NTSC One Chip Decoder, TDA3562A.

I have seen pictures of two different designs for the second control box, Peter Kretzschmar's Video Wall has a simple video amplifier/splitter board installed with the demodulator board. Mike's board shown here has a much more complex Distribution Amplifier board  - this one has eight RGB outputs.


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