Akai Deep Impact SB1, Руководство по обслуживанию, Страница: 2 / 10

SERVICE MANUAL
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SAFETY INSTRUCTIONS
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INFORMATIONS
SYMBOLS FOR PRIMARY DESTINATION
Unit destinations are indicated with letters as shown below.
Symbols Principal Destinations
A U.S.A
B U.K
C Canada
E Europe (except U.K)
J Japan
S Australia
V Germany
U Universal Area
Y* Custom version
1. Parts identified by the
}
symbol are critical for safety.
Replace them only with the parts number specified.
2. In addition to safety, other parts and assemblies are
specified for conformance with such regulations as those
applying to spurious radiation.
These must also be replaced only with the specified
replacements.
Examples : RF converters, tuner units, antenna selector
switches, RF cables, noise blocking capacitors,
noise blocking filters, etc.
3. Use specified internal wiring. Note especially :
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads
4. Use specified insulating materials for hazardous live parts.
Note especially :
1) Insulation Tape
2) PVC tubing
3) Spacers (insulating barriers)
4) Insulation sheets for transistors
5) Plastic screws for fixing micro switches
5. When replacing AC primary side components (trans-
formers, power cords, noise blocking capacitors, etc.), wrap
the ends of the wires securely around the terminals before
soldering.
6. Make sure that wires do not contact heat producing parts
(heat sinks, oxide metal film resistors, fusible resistors,
etc.).
7. Check that replaced wires do not contact sharp edged or
pointed parts.
8. Also check areas surrounding repaired locations.
9. Make sure that foreign objects (screws, solder droplets,
etc.) do not remain inside the set.
SAFETY CHECK AFTER SERVICING
After servicing, make measurements of leakage-current or
resistance in order to determine that exposed parts are
acceptably insulated from the supply circuit. The leakage-
current measurement should be done between accessible
metal parts (such as chassis, ground terminal, microphone
jacks, signal input/output connectors, etc.) and the earth ground
through a resistor of 1500 ohms paralleled with a 0.15
µ
F
capacitor, under the unit’s normal working conditions.
The leakage-current should be less than 0.5 mA rms AC. The
resistance measurement should be done between accessible
exposed metal parts and power cord plug prongs with the
power switch (if included) “ON”. The resistance should be
more than 2.2 M ohms.