Orion L77-17, Инструкция по эксплуатации

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SECTION 8
Maintenance
8.1 Replacing Sub Assemblies
The connections are mainly plug-in, and wrong connection is unlikely, but special
attention should be taken to the configuration when removing items. Repair and
replacement should only be done by experienced personnel who are aware of the
dangers of working on line-operated equipment. Power must be turn off when changing
sub-assemblies, and the technician should dissipate any static charges before
handling parts, by touching the grounded cabinet.
The MBIA can be removed by removing the four screws securing the chassis to the
back plate. Unplug the various terminal connectors, the ribbon connector, the
disconnect terminals and remove the unit. Removing two securing screws and then
unplugging can individually replace the THREE DC DRIVE controls. An on-board
AGC-8 fuse, accessible when the drive control has been unplugged, protects each
control.
The microprocessor board on the inside of the cabinet door connects by ribbon cable
to the MCIA. The ribbon cable should be unplugged before removing the PCB. The
microprocessor board is held in place by six #6 nylon nuts. When these nuts are
removed, the microprocessor board can be unplugged from the keyboard/display by
gently pulling it out. The keyboard display can be removed by releasing the six nylon
hex threaded spacers.
8.2 Board-Level Maintenance
In most cases, repair is beyond the scope of field service, without special equipment.
However, the motherboard does contain replaceable items – the control fuse (AGC ½
Amp), and the carriage reversing relays.
SECTION 9
Trouble-Shooting
When operating the machine manually, if the carriage can be raised/lowered, it is
assumed the carriage section to be functional. If the turntable can be jogged, this
section too should be functional. If the film control responds to a light pull on the film,
feeding freely, this section is also functional. If only one of these functions does not
respond, the appropriate drive module can be unplugged and its fuse can be
examined. If the fuse is blown, it should be replaced only with the recommended type
and value. If the fuse immediately blows again, it is probably because one or more of
the power devices is shorted. The proper devices should be used for replacement.
If there are problems reversing the carriage drive, and/or the relays show signs of
burned contacts, these should be replaced. They are plug-in devices.
If the Display is not lit, displays anomalous characters, or does not respond to
keyboard input, the problem could be a problem with the Microprocessor PCB.
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