In this teardown video I’ve got something pretty cool; a black box from an RAF Nimrod MRA4 which was a failed project and numerous aircraft were built but were never delivered to the RAF and were later scrapped. This one does show some signs of wear and tear although it may well be damage due to storage and this unit looks like it has never actually been used. The locator beacon on the front which is a circular tube containing a battery and the radio beacon itself is missing however everything else is present.
It is a solid state recorder utilizing 128Mb of flash memory to store the audio recordings and it is buffered and compressed by the electronics to reduce file size and therefore increase recording time. I found the recorder to be functional as I managed to power it up but unfortunately I was unable to access the recordings or the built in serial menu via the RS232 port on the front panel.
The recorder is powered by two microcontrollers; a Philips 80C51 clone which looks like it serves as the boot processor and a 32 bit AMD AM29200-20 as the main application processor. The boot ROM is stored in a 128kb OTP PROM (which I have dumped) and the device’s operating system (probably some kind of RTOS) and the application that actually runs the device is stored in separate 512Kb of onboard flash. This looks like it is flashed / updated via the serial port on the front panel. Unfortunately it seems that this flash has likely been erased to prevent re-use. The firmware that is stored in the 8051 clone chip hasn’t been dumped yet and I’ve yet to determine it’s exact function.
A youtube video of it is here and below you can also find a photo album showing the internal components and circuit boards.
