File:BG Model 250 Controller Internal 1.jpeg|Power supply on the right with EMI Suppression on the bottom. Control PCB's on the top with ribbon cable that plugs into front panel PCB.
File:BG Model 250 Controller Internal 2.jpeg|Internal view from the other side
File:BG Model 250 Controller Processor Board.jpeg|Processor board runs on a Motorola 6803 8-bit microcontroller at 4.9152 MHz with an external 8k RAM, 64k EEPROM and an unknown size a 256k EPROM with version sticker on it.
File:BG Model 250 Controller Processor Board Back.jpeg|Back of processor board, small jumper wire seen on the top right side. This is present on two different processor PCB's I have, not just a manufacturing defect with this board.
File:BG Model 250 Controller IO Board Front.jpeg|IO Board used to drive valves in Acid Etching unit. a buzzer is on the bottom middle which is triggered when there are errors or user interaction needed in the process.