Akai AM 75 Service Manual

Page 2

*SAFETY INSTRUCTIONS

PRECAUTIONS DURING SERVICING

1. Parts identified by the A (*) symbol are critical for
safety. Replace only with parts number specified.

2. In addition to safety, other parts and assemblies are spe-
cified for conformance with such regulations as those ap-
plying to spurious radiation.

These must also be replaced only with specified replace
merits.

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 microswitch (especially in
turntable)

5. When replacing AC primary side components (trans~
formers, power cords. noise blocking capacitors, etc.),
wrap ends of wires securely about the terminals before
soldering.

natal

6. Observe that wires do not contact heat producing parts
(heatsinks. oxide metal film resistors, fusible resistors,
etc.).

*INFORMATION

7. Check that replaced wires do not contact sharp edged or
pointed parts.

8. Also check areas surrounding repaired locations.

9. Use care 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 ac»
ceptably 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 resister Of1500 Ohms paral-
leled with a 0.15 uF capacitor, under the units normal
working conditions. The leakage-current should be less
than 0.5 mA rms AC.

The resistance measurement should be done between ac,
cessible exposed metal parts and power cord plug prongs
with the power switch (if included) ON. The resistance
should be more than 2.2 Mohms.

SYMBOLS FOR PRIMARY DESTINATION

Alphabet indicates the destination of the units as listed
below.

Symbols Principal Destinations

USA
UK

Canada

Europe (except UK)

Japan
Australia

W. Germany only
Universal Area

Custom version

SERVICE MANUAL

VOLTAGE CONVERSION (I Model only)

Before connecting the power cord. Set the V9 LTAGE SE-
LECTOR located on the rear panel with a stewdriver so
that the correct voltage is indicated.

120v 110v
240v 220v
VOLTAGE SELECTOR _*

Page 50

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