Editing Apple Multiple Scan 20 Display (section)

== Hardware ==
Behind the rear housing and the EMI shield the display has a power supply with an AC interconnect board, a main deflection board, a CRT/video board on the neck of the tube, a microprocessor control board, a serial I/O board, a focus control box and an ADB board in the stand.<ref name="ss20" /> Other service parts are the AC inlet (922-0696), control panel (922-0684), focus VR control (922-0733), serial I/O board (922-0686), base ADB board (922-0687), video cable (922-0732) and tilt/swivel assembly (922-0697). The CRT itself was not offered as a part.<ref name="sgparts" />

The fuse is on the power supply. The Service Source only says to replace it with one of the same current and voltage rating; Apple's parts list in the service guide gives it as 6.3 A, 250 V (922-0735, packet of ten).<ref name="ss20" /><ref name="sgparts" />

Each display keeps its own adjustment data in an EEPROM on the microprocessor control board. Apple's procedure saves it to a file over a mini DIN-8 serial cable before that board is changed and writes it back to the new board afterwards. If the data is lost first, Apple says the display cannot be repaired and has to be replaced.<ref name="ss20" /><ref name="sgparts" />