BeebMaster's Greatest
Ever Find!!!
BBC
Master
512
Inside this machine is the 80186 co-processor board, mounted to the left of the main PCB. The square chip in the middle is the Intel 80186 processor which runs very hot. There is no on-board fan and this thing does get incredibly warm.
On its own the 512 board would make this machine special but the expansion goes on. There are two ROM expansion boards mounted in two of the ROM sockets to the right of the machine. The first board is longways flush with the speaker mounting and the other is a more square board which starts two sockets up from the first board.
The boards contain, amongst other things, Inter-Word, Master ROM, Overview and Exmon II. On the second board is the updated Acorn MOS 3.50 which I have never seen before.
The first board has a wire leading to the yellow device just above the speaker. This is in fact a hook which is released by pressing the end of the yellow plastic housing. It hooks onto pin 2 of one of the ICs and the machine will not work without this.
There is also a switch from one of the ROM boards. The switch rests in the bay between the power supply and the PCB. It has three positions - left, middle and right - but I am yet to work out what this does.
The Master 512 even has its own special battery pack in red plastic, seen to the left of the keyboard.
 |
 |