Editing Amstrad CPC 464 Maintenance Guide (section)

== Opening the System Unit ==

Tools: Philips #1 and #2 screwdriver, anti-static strap.

# Power off the system unit and unplug the DC power from the monitor.
# Disconnect any joystick, printer or expansion-port peripherals.
# Place the keyboard face-down on a soft cloth.
# Remove all screws on the underside of the case. The number varies by revision (typically 6&ndash;8); some have additional screws beneath the model-name label.
# Carefully lift the lower half of the case. The cassette deck and main PCB remain attached to the upper half on most revisions.
# Disconnect the keyboard ribbon (or discrete wires on the original revision) from the main PCB at '''CP002'''. Note the orientation; on revisions with discrete wires, photograph the colour order before removing.
# Disconnect the cassette sub-PCB ribbon at '''CP001'''. The cassette sub-PCB carries IC301 (audio amp LA4140), IC302 (cassette read amp LA6324), the motor relay and the cassette head switches.

The volume potentiometer (VR301), the speaker and the cassette head connect to the cassette sub-PCB; the main PCB does '''not''' carry any of these. Both PCBs must be removed together if work on the cassette electronics is required.