This navigation computer was purchased with the intent of extracting some mil-spec chips from the boards. Based on some research, it is likely that this unit would have been used in a military transport aircraft such as the C-130J or C-27J. The metal casing is pretty unassuming, but there is a fascinating collection of boards contained within. All boards are slotted into a common backplane along with a dedicated power supply card. There is a nice metal mil-spec fan along with an impressive multipin connector. Each pin from this connector appears to have been manually wired to the bottom side of the backplane board. There are many mil-spec chips including some custom Honeywell and Sperry ones. Just about all the chips are ceramic packages, many with gold or metal lids, indicating high reliability or mil-spec. There is a very thick layer of conformal coating that covers both sides of all boards. It looks like the boards were actually dipped in the coating. We tried scrubbing vigorously with isopropyl alcohol and acetone. That mostly worked, but was very time consuming and turned the conformal coating into a sicky mess. Much to our surprise, a hot air SMD rework station set at 660 degrees Fahrenheit worked perfectly. Spending only a few minutes over each chip and carefully prying up with a screwdriver allowed us to cleanly remove several of the chips.