Penny & Giles aircraft cockpit voice recorder (black box) teardown from RAF Nimrod MRA4.

I picked up an aircraft black box that came from the failed Nimrod MRA4 project that was picked up cheap on eBay. The "black box" is actually bright orange and has reflective striped across the casing. It is around 20 years old (manufactured 06/2000) and utilizes solid state recording using flash memory as the storage medium. I was interested to see if I could extract any data from it but unfortunately that was not possible although I was able to power it up as it only needed 28V dc to work. It made for an interesting teardown anyway and now would make a suitable man cave item. The internal circuit boards consist of a power supply board, an audio processing and compression board, the main CPU board and the flash interface board. The CPU board has two microcontrollers; an 80C51 and an AMD 29200 along with flash memory, ROMS, RAM and the usual stuff. I also dumped one of the ROMS (the boot ROM) and managed to extract some of the serial menu from the code that is sent over the RS232 port on the front. Upon further inspection this unit has a boot ROM and the actual program that runs the CVR is stored in flash. The application firmware is upgradeable and erasable via the front panel serial port and it appears that it has indeed been erased. Most likely to prevent re-use. I would assume the data storage module for the recordings has been erased too. Photos of the internal electronics can be found on my blog at https://www.adrian-smith31.co.uk/blog... Photo of main CPU board showing firmware flash, CPU and RAM used in this unit https://www.adrian-smith31.co.uk/blog... Timestamps:- Part 1: Teardown of control electronics 4:00 Part 2: Teardown of audio storage module 12:05 Part 3: ROM dumping and a look at the code 18:15 #electronics #avionics #nimrodmra4 #aircraft