This is an extremely rare layout for a NMB keyboard being that has an ANSI return key and 2u backspace key. This board come with linear Hi-Tek 725 series switches which I will get into later why this version is one of the rarest that I have ever found.
Top of board:
I wish I had a macro lens but there are still some good photos from sandy55 showing the rare switches. The reason that these space invaders are so rare because of the colour of plastic that was used. Normally all linear switches that are made with a white slider. So with this in mind the switches in this board are actually clickly but they are white but they are still linear!?
What is really going on here? Well it turns out that they decided to mold clicky switches and use white plastic. Now normally clicky would be done in black plastic. Next is where this gets even better, since the board is a terminal keyboard and they are normally linear they just decided not to put the clicker in. Since the contacts for both linear and clicky switches are the same then we have clicky white linear switches.
Top of slider:
The board come with a ps2 connector but if you use a simple ps2 to usb converter you will run into issues. It seems like this board likes to speak a version of the AT protocol. Seems like there also could be a version that speak XT but this hasn't been found yet to my knowledge.
PCB and Pinout: