Sanyo FXD-680GD, Service Manual

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SERVICE NOTES AND PRECAUTIONS:
Service notes:
1. Make sure that the power lead is connected properly to
Power source, otherwise damage to radio may result. If a
Battery, eliminator is used as a power source in place of a
Battery, it must be filtered and regulated. (The power sup-
ply capacity should be more than 5 amps).
2. Integrated circuits (ICs) are used in this unit. Because the
ICs are direct-coupled devices, as to all electronic equip-
ment, reading within 10% of the indicated values are acc-
eptable. Allowance must also be made for variations in
supply voltage. It is expected that any breakdown within
the IC results in drastic changes of the operating voltages
at the terminals.
3. When replacing a power output IC, remember to use the
IC specified in the parts list; Coat the IC-fin with silicon
grease.
WARNING
In using meters, signal generator and any tool in servicing
ICs, extreme care is needed.
DO NOT SHORT THE IC TERMINALS TO THE PATTERN
ON THE PC BOARD OR TO EACH OTHER. THE IC WILL
BE INSTANTANEOUSLY DESTROYED.
Adjustment procedure:
Alignment is performed at factory with laboratory equipment.
Therefore, before alignment is attempted, the unit should be
thoroughly checked for circuit troubles.
Notes:
1. Check for specified source voltage-DC, 14.4 volts.
2. Connect an AC voltmeter (AC VM) across speaker or
dummy load (4 ohms. 20W, wire wound resistor)….see
fig. 1-3. (ELECTRICAL ADJUSTMENTS).
3. Signal input must be kept as low as possible to avoid
overload and clipping (use highest sensitivity of output
indicator).
4. Repeat adjustment to ensure good results.
5. Non-metallic alignment tools, must be used (especially
at FM alignment).
6. for alignment location details, refer to CIRCUIT BOARD
PARTS LOCATIONS
Installation procedure:
1. To prevent a short circuit, remove the key from the ignition
and disconnect the battery.
2. Make the proper input and output wire connections for
each unit.
3. Connect the wiring harness wires in the following order:
ground, sealers, battery, ignition.
4. Connect the wiring harness connector to the unit.
5. Install the unit in your car.
6. Reconnect the battery.
7. Disentails by reversing the installation procedure.
CAUTION
● The rear-panel which also heat sink is very hot. Don’t
burn!!
● If your car’s ignition does not have an ACC position,
connect the ignition wires to a power source that can
be turned on and off with the ignition key. If you connect
the ignition wire to a power source with a connect voltage
supply, as with battery wire the battery may die.
● If the console has a lid, make sure to install the unit so
that the cover will not hit the lid when closing and open-
ing.
● If the fuse blows, first make sure the wires aren’t touch-
ing to case a short circuit, then replace the old fuse with
one with the same rating.
● Do not let unconnected wires or terminals touch metal
on the car or anything else conducting electricity. To
prevent a short circuit, do not remove the caps on the
ends of the unconnected wires or the terminals.
● Connect the speaker wires correctly to the terminals to
which they correspond. The unit may be damaged or
fair to work if you share the wires or ground them to
any metal part in the car.
● After the unit is installed, check whether the brake lamps,
blinkers, wipers, etc. On the car are working properly.
● Insulate unconnected wires vinyl tape or other similar
material.