First view of the R-8 MKII's innards. The topmost circuit board (orange) is the Jack Board Assembly. Beneath it is the much larger CPU Board (motherboard), which houses the unit's memory backup battery (3V). Beneath the CPU Board is a thick sheet of aluminized plastic shielding. This shielding hides 3 more important components: the circuit board for Key Pads 1 -16, the main switchboard assembly and the LCD circuitry.
Time to see what lies underneath the CPU Board and shielding.
With the CPU Board and shielding out of the way, we can see the 3 hidden components. Clockwise from left: Key Pad circuit board assembly, LCD circuitry and main switchboard assembly.
Closer view of the 3 hidden components. Note that the Key Pad circuit board has a metallic base, while both the LCD circuitry and main switchboard are protected by a sheet of plastic.
These are the screws that had to be painstakingly removed (and reinstalled after this adventure) in order to examine the R-8's innards.