C130J-MQTP

J6 on the Mission Computers is a program plug. A lot of the avionics on C-130Js are commercial off the shelf COTS or have redundant systems. It let's an LRU know what position it's in #1 vs #2, what remote terminal address to use for the data, and other data depending on how configurable the manufacturer made it. For example that's how the pilot's interphone control panel knows it's in the pilot's position when sending commands to the CSU. If you've seen any of the old PMA cases there is this small metal plug (or long red cable/plug made of the same material as the PMA cables) that they don't use anymore. That plug used to be used on J6 for loading software to the CNI-SPs because without it the MCs wouldnt know that they need to take over as bus controller for the com/nav busses.

You should have messed with the old green monster PMA, now that was a POS. I'd have to see this problem for myself though, APN-241 does it's own internal BIT and just feeds the results to the PMA. Did you get any fault codes or was it just the generic "Radar Degraded" ACAWS? Which Mission Computer were you using in OMP? can you repeat the write up? The plane isnt going to a windows based system just the PMA/GMS, might not even see a change in the GUI.