Serial RS232 Seat Power

[aviationteacher]

Hi everyone--first post for me, so here goes.

I recently came into possession of a pair of ex-Northwest Airlines business class seats from a DC-10. One in the pair has a video monitor that comes out of the armrest. The monitor is labeled "Northwest Worldlink", a defunct system aboard early 90s long-haul NW airplanes. There is also a remote control on the side which has several buttons like flight attendant call, light, and video selecting/game controls -- but I believe that feature was long turned off/disabled.

Coming out from below the seats are three cables: an electrical (black)-wrapped 9 pin male serial cable, a soft sided silver wrapped wire containing nine very small thin cables, and a red/white cable which I believe is for the headphone jack.

Any thoughts on which is the power and which is the remote? How was it powered? And, if possible, can I get it running again or send a signal to the monitor?

Thanks! See attached photo of the serial cable and wrapped wire.

UPDATE: I found the US Patent and electrical designs...hopefully someone can decode it for me. The system was called Hughes-Avicom APAX-150.
https://docs.google.com/viewer?url=patentimages.storage.googleapis.com/pdfs/US5311302.pdf

 

[FoxyRick]

I can't be much help, but I doubt the 9-pin connector is RS232 serial. The patent describes using an Arcnet LAN for communication with the central computer. No mention is made of RS232 as an external interface. Arcnet is a token-passing bus network and not something you can just plug into a PC and bring up a terminal.

The video/audio interface is likely similar to a cable TV signal. Multiplexed channels on differing frequencies. Not something easy to use without really knowing the fine details.

The patent isn't really much help because it's a block diagram with only suggestions of what components and protocols to use, and it's clearly a complex system. Fascinating, though. My tiny experience on aircraft systems predates this by a fair bit. What you need is actual schematics and pinouts.

You might get lucky and someone around here will have worked on the system... would be an interesting project.