AWA MHDV2245-O3-D0, Руководство по обслуживанию

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1-3-6 Safety Check after Repairment
- 04 -
Service Manual
Model No.:
Confirm that the screws, parts and wiring which were removed in order to service are put
in the original positions, or whether there are the positions which are deteriorated around
the serviced places serviced or not. Check the insulation between the antenna terminal or
external metal and the AC cord plug blades. And be sure the safety of that.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power source before;
a. Removing or reinstalling any component, circuit board module or any other receiver
assembly.
b. Disconnecting or reconnecting any receiver electrical plug or other electrical
connection.
c. Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic
capacitors may result in an explosion hazard.
2. Test high voltage only by measuring it with an appropriate high voltage meter or other
voltage measuring device (DVM, FETVOM, etc) equipped with a suitable high voltage
probe.
Do not test high voltage by "drawing an arc".
5. Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this
service manual might be equipped.
8. Use with this receiver only the test fixtures specified in this service manual.
CAUTION:
Do not connect the test fixture ground strap to any heat sink in this rec
eiver.
3. Do not spray chemicals on or near this receiver or any of its assemblies.
4. Unless specified otherwise in this service manual, clean electrical contacts only by
applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or
comparable non-abrasive applicator; 10% (by volume) Acetone and 90% (by volume)
isopropyl alcohol (90%-99% strength).
CAUTION:
This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of contacts is not required.
Capacitors may result in an explosion hazard.
6. Do not apply AC power to this instrument and/or any of its electrical assemblies unless
all solid-state device heat sinks are correctly installed.
7. Always connect the test receiver ground lead to the receiver chassis ground before
connecting the test receiver positive lead.
Always remove the test receiver ground lead last. Capacitors may result in an explosion
hazard.
9. Remove the antenna terminal on TV and turn on the TV.
10. Insulation resistance between the cord plug terminals and the eternal exposure metal
should be more than Mohm by using the 500V insulation resistance meter.
11. If the insulation resistance is less than M ohm, the inspection repair should be required.
If you have not the 500V insulation resistance meter, use a Tester. External exposure
metal: Antenna terminal Headphone jack