akira VCR-S407, Service Manual

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Model No.: VCR-S407
Version: 1.0
11. High voltage is maintained within specified limits by close-tolerance, safety-related components and
adjustments. If the high voltage exceeds the specified limits, check each of the special components.
12. Design Alteration Warning:
Never alter or add to the mechanical or electrical design of this unit. Example: Do not add auxiliary
audio or video connectors. Such alterations might create a safety hazard. Also, any design changes or
additions will void the manufacturer’s warranty.
13. Hot Chassis Warning:
Some TV receiver chassis are electrically connected directly to one conductor of the AC power cord.
If an isolation transformer is not used, these units may be safely serviced only if the AC power plug
is inserted so that the chassis is connected to the ground side of the AC source.
To confirm that the AC power plug is inserted correctly, do the following: Using an AC voltmeter,
measure the voltage between the chassis and a known earth ground. If the reading is greater than
1.0V, remove the AC power plug, reverse its polarity and reinsert. Re-measure the voltage between
the chassis and ground.
14. Some TV chassis are designed to operate with 85 volts AC between chassis and ground, regardless
of the AC plug polarity. These units can be safely serviced only if an isolation transformer inserted
between the receiver and the power source.
15 Never defeat any of the B+ voltage interlocks. Do not apply AC power to the unit (or any of its
assemblies) unless all solid-state heat sinks are correctly installed.
16 Always connect a test instrument’s ground lead to the instrument chassis ground before connecting
the positive lead; always remove the instrument’s ground lead last.