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The Memotech MTX Series

Memotech Photos - Multi-Effect Video Wall

Dave's Video Wall

System 2


If you click on the images below, the full size picture will open, be aware, many of these are quite large and may be unsuitable for display on mobile devices or with a slow internet connection, but I wanted to include as much detail as possible in the larger photos


My Video Wall Hardware

This photo is of Video Wall hardware listed on ebay in September 2015 as a "Memotech MTX2000 Video Wall controller PC".
This particular Video Wall system was obviously designed to be portable and, apart from the monitors and video source, is self-contained. As shown in the photo, an MTX512S2 keyboard was permanently fixed inside the case.

Although the ebay photos didn't give any indication that this was an MTX2000 system, the module below the keyboard appears to show an integral 3.5" floppy disk drive and suggested that this was an unusual piece of Memotech kit.
This is the rear view inside the flight case, showing :
1 x Control module  
1 x Decoder module  
2 x DDFS modules supporting a 4 x 4 Video Wall

The control module appeared to be very similar to my Reflex Controller, but with the keyboard connector being utilised, this system definitely had a different configuration.

Since this system appeared to be complete and potentially built using an MTX2000 computer, I made an offer for the equipment which was accepted.

Close up / detailed photos - the full size pictures are quite large!


Computer - MTX2000


Although carrying an MTX512S" label, the keyboard in this system is just that - a standard MTX keyboard with the rest of the original components removed from the case.  
The MTX2000 system unit consists of a MTX 4000-04 computer board with the majority of the power supply components removed and power supplied from a "Skynet", Model Number SNP-3031 PSU as was fitted to the Reflex Controller in my other Video Wall system.  
In line with Geoff Boyd's recollections of the MTX2000, the system includes a 3.5" floppy drive and a ROM based CP/M system using Andy's SCPM ROM.

The disk controller is the same as that used in the second version of the SDX, it has space for 512kB of RAM, but the sockets are unpopulated.
Solder side of the disk controller board

 - yes, yellow wire features again!
A combined RS232 / EPROM board is mounted vertically, soldered to the MTX computer board edge connector.

The EPROM sockets are unpopulated, the system would have needed to have the Video Wall program and sequences loaded from disk.

The Video Wall Hardware




The Video Wall Controllers  - DDFS (Distributed Digital Frame Store)


When I removed the lower DDFS from the flight case, there were no obvious markings on it, so I assumed that it was just another unbranded DDFS.

When I started to reassemble it after cleaning, I found that the front of the case had been fitted upside down! - The DDFS was actually labeled as a "Memopix Video Wall 2000 HI RES".
Rear view of the lower Video Wall Controller (DDFS).

The RGB monitor output connector labels suggest that this DDFS should be connected to monitors 9 to 16, with an additional output labeled "0".
The Serial Number label from the lower Video Wall Controller (DDFS).

The serial number (1410) is a quite close to my other Video Wall DDFS (1451), but the label confirms that this is a High Resolution "200" series, rather than the Standard Resolution of my series "150" unit.
One of the Frame Store Memory Boards (FSMB)

The "Frame Store Memory Board - Double Resolution" PCB is the same board as fitted in my other Video Wall DDFS , although the ROMs are different. This is also an "86/07 Issue 5 board", with what appears to be a Date Code of "89 04".

The RAM chips fitted to this board are 22-pin 64kx1 SRAMs (256x256), rather than the 20-pin 16kx1 (128 x 128) SRAMs in my series "150" DDFS.

Solder side of the Frame Store Memory Board
The FSMBs are uniquely addressed by configuration programmed into the PAL in IC27, in this DDFS, the addresses are as shown :

FSMB Address

Slot Left Side Right Side
5 FS143 FS139
4 FS142 FS138
3 FS141 FS137
2 FS140 FS136
1 (empty) (empty)
0 (FSAD board) (FSAD board)

FSMB Address

Slot Left Side Right Side
5 FS135 FS131
4 FS134 FS130
3 FS133 FS129
2 FS132 FS128
1 (empty) (empty)
0 (FSAD board) (FSAD board)

The Serial Number label from the upper Video Wall Controller (DDFS).


Video Decoder & Distribution Amplifier






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