Mackie FR Series M-1200, Service Manual

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VERSION 1.1
SERVICE PROCEDURES
11
SERVICE PROCEDURES
MECHANICAL PROCEDURES
The M•1200/M•1400 design allows easy removal of all components and assemblies.
Disassembly and reassembly should be self evident. This manual has exploded
diagrams in the parts section.
Several important points concerning the assembly:
• 4 of the screws that secure the top cover also hold the front extrusion (curved
piece) in place. When removing the top cover, be careful that the front extrusion is
not dropped.
• If the MAIN PCB is removed, be sure the smaller head machine screws (750-050-04)
are replaced next to the filter caps. The larger head machine screws can arc to the
capacitor body.
• Be sure all tywraps are replaced and that no wires are in danger of being pinched
in-between the cover and heatsink.
REQUIRED EQUIPMENT LIST
• 30 MHz dual trace oscilloscope
•
DMM (Must be capable of measuring 8mV DC with a minimum of 2 digits of
accuracy, and down to .1
Ω )
• Sine wave oscillator / Function generator (20Hz - 20KHz)
• 4 load resistors (8 Ω with a minimum 500W power rating)
• 10A / 120V Variac With AC voltmeter and a defeatable ammeter (1 Amp full range)
or wattmeter (300 Watts full range)
•
0.1uF 400V film capacitor installed across dual banana plug
• 16 AWG shorting jumper installed across dual banana plug
RECOMMENDED EQUIPMENT LIST (PERFORMANCE VERIFICATION)
• Distortion analyzer and low distortion oscillator.
(Capable of resolving distortion as low as 0.002% from 20Hz to 20KHz)
•
2500W AC power source.