Motorola HT 1000 ユーザーズマニュアル

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Alcohol is a high-wetting liquid and can carry contamination into 
unwanted places if an excessive quantity is used. Make sure that 
controls or tunable components are not soaked with the liquid. Do not 
use high-pressure air to hasten the drying process, since this could 
cause the liquid to puddle and collect in unwanted places.
Upon completion of the cleaning process, use a soft, absorbent, lintless 
cloth to dry the area. Do not brush or apply any isopropyl alcohol to 
the frame, front cover, or back cover.
NOTE:
Always use a fresh supply of alcohol and a 
clean container to prevent contamination by 
dissolved material (from previous usage).
Safe Handling of 
CMOS Devices
Complementary metal-oxide semiconductor (CMOS) devices are used 
in this family of radios. While the benefits of CMOS are many, their 
characteristics make them susceptible to damage by electrostatic or 
high voltage charges. Damage can be latent, resulting in failures 
occurring weeks or months later. Therefore, you must take special 
precautions to prevent device damage during disassembly, 
troubleshooting, and repair. Handling precautions are mandatory for 
CMOS circuits, and are especially important in low humidity 
conditions. DO NOT attempt to disassemble the radio without first 
referring to the CMOS CAUTION paragraph in the Disassembly and 
Reassembly section of the manual.
Repair Procedures 
and Techniques
Refer to the Disassembly and Reassembly section of the manual for 
pertinent information prior to replacing and substituting parts.
General
Parts Replacement and 
Substitution
Special care should be taken to be as certain as possible that a 
suspected component is actually the one 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.
When damaged parts are replaced, identical parts should be used. If 
the identical replacement component is not locally available, check 
the parts list for the proper Motorola part number and order the 
component from the nearest Motorola Communications Parts office 
listed in the “Replacement Parts Ordering” section of this manual.
Rigid Circuit Boards
This family of radios 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.
When soldering near the module socket pins, use care to avoid 
accidentally getting solder in the socket. Also, be careful not to form 
solder bridges between the module socket pins. Closely examine your