Marantz NA8005, Service Manual

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SAFETY PRECAUTIONS
The following items should be checked for continued protection of the customer and the service technician.
leakage current check
Before returning the set to the customer, be sure to carry out either (1) a leakage current check or (2) a line to chassis
resistance check. If the leakage current exceeds 0.5 milliamps, or if the resistance from chassis to either side of the
power cord is less than 460 kohms, the set is defective.
Be sure to test for leakage current with the AC plug in both polarities, in addition, when the set's power is in each state
(on, off and standby mode), if applicable.
CAUTION
Please heed the following cautions and instructions during servicing and
inspection.
◎ Heed the cautions!
Cautions which are delicate in particular for servicing
are labeled on the cabinets, the parts and the chassis,
etc. Be sure to heed these cautions and the cautions
described in the handling instructions.
◎
Cautions concerning electric shock!
(1) An AC voltage is impressed on this set, so if you
touch internal metal parts when the set is energized,
you may get an electric shock. Avoid getting an
electric shock, by using an isolating transformer
and wearing gloves when servicing while the set is
energized, or by unplugging the power cord when
replacing parts, for example.
(2) There are high voltage parts inside. Handle with
extra care when the set is energized.
◎ Caution concerning disassembly and
assembly!
Through great care is taken when parts were
manufactured from sheet metal, there may be burrs on
the edges of parts. The burrs could cause injury if fingers
are moved across them in some rare cases. Wear gloves
to protect your hands.
◎
Use only designated parts!
The set's parts have specific safety properties (fire
resistance, voltage resistance, etc.). Be sure to use parts
which have the same properties for replacement. The
burrs have the same properties. In particular, for the
important safety parts that are indicated by the
z
mark
on schematic diagrams and parts lists, be sure to use
the designated parts.
◎ Be sure to mount parts and arrange the wires
as they were originally placed!
For safety seasons, some parts use tapes, tubes or other
insulating materials, and some parts are mounted away
from the surface of printed circuit boards. Care is also
taken with the positions of the wires by arranging them
and using clamps to keep them away from heating and
high voltage parts, so be sure to set everything back as
it was originally placed.
◎ Make a safety check after servicing!
Check that all screws, parts and wires removed or
disconnected when servicing have been put back in their
original positions, check that no serviced parts have
deteriorate the area around. Then make an insulation
check on the external metal connectors and between
the blades of the power plug, and otherwise check that
safety is ensured.
(Insulation check procedure)
Unplug the power cord from the power outlet, disconnect
the antenna, plugs, etc., and on the power. Using a 500V
insulation resistance tester, check that the insulation
resistance value between the inplug and the externally
exposed metal parts (antenna terminal, headphones
terminal, input terminal, etc.) is 1MΩ or greater. If it is
less, the set must be inspected and repaired.
Many of the electric and the structural parts used in the
set have special safety properties. In most cases these
properties are difficult to distinguish by sight, and the use
of replacement parts with higher ratings (rated power
and withstand voltage) does not necessarily guarantee
that safety performance will be preserved. Parts with
safety properties are indicated as shown below on the
wiring diagrams and the parts list in this service manual.
Be sure to replace them with the parts which have the
designated part number.
(1) Schematic diagrams .......Indicated by the
z
mark.
(2) Parts lists .......Indicated by the
z
mark.
The use of parts other than the
designated parts could cause electric
shocks, fires or other dangerous
situations.
CAUTION Concerning important
safety parts
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