Motorola Astro Dimetra MTP, Instruction Manual

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11. Wrap CMOS modules in conductive material when transporting
them from one area to another, even within the same room. Use
wrapping material similar to that in which replacement modules
are wrapped when they arrive from the factory. (You can also use
aluminum foil.) Never use nonconductive material for packaging
these modules.
Soldering
Leadless component technology requires the use of
specialized equipment and procedures for repair and servicing
of the XTVA. If you are not totally familiar with leadless
component repair techniques, it is strongly recommended
that you either defer maintenance to qualified service
personnel and service shops, or take the recommended video-
taped component repair training program, MAV-PACK 3 (VID-
952). This is of paramount importance as irreparable damage
to the XTVA can result from service by unauthorized persons.
Unauthorized attempts to remove or repair parts may void any
existing warranties or extended performance agreements with
the manufacturer.
Special care must be taken to be as certain as possible that a suspected
component is actually at fault. This special care will eliminate
unnecessary unsoldering and removal of parts, which could damage or
weaken other components or the printed circuit board itself.
Rigid Circuit Boards
The XTVA uses bonded multi-layer printed circuit boards. Since the
inner layers are not accessible, some special considerations are
required when soldering and unsoldering components. The printed-
through holes may interconnect multiple layers of the printed circuit.
Therefore, care should be exercised to avoid pulling the plated circuit
out of the hole. Closely examine your work for shorts due to solder
bridges.
Flexible Circuits
The flexible circuits are made from a different material than the rigid
boards, and different techniques must be used when soldering.
Excessive prolonged heat on the flexible circuit can damage the
material. Avoid excessive heat and excessive bending. For parts
replacement, use the ST-1087 Temperature-Controlled Solder Station
with a 600 or 700 degree tip, and use small diameter solder such as ST-
633. The smaller-sized solder will melt faster and require less heat
being applied to the circuit.
Parts Replacement and
Substitution
When defective parts or components must be replaced, identical parts
should be used. If the identical replacement part is not locally
available, check the electrical and exploded view parts lists for the
correct Motorola part number. Order the part from the nearest
Motorola Communications Parts office as listed under “Replacement
Parts Ordering” on the inside back cover of this manual.
If, for any reason, substitutions must be made, reinstall the exact
replacement part as soon as possible to ensure optimum performance.
The substituted part must have identical electrical characteristics and
must have equal or higher voltage and current ratings.
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