Anritsu RA725UA, Instruction Manual

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HIGH VOLTAGES
Although this radar presents no dangers in normal usage, dangerous high voltages are
used inside the equipment. Observe the following safety precautions when repairing or
inspecting the radar.
1. Always set the display POWER switch, and the main switch for the radar on the
distribution
board to OFF.
2. Even after setting these switches to OFF, there may be high residual voltage at the
anode cap of the CRT, at the
300-volt
line of the
scanner connection cable, at the
scanner 300-volt circuit, and at the PFN (pulse adjustment
circuit)
of the MOD PC
board Ground these points using a conductor such as a
wire
lead or screwdriver
whose
one end is grounded
and check that there is no residual voltage with a tester.
REPAIRING AND INSPECTING SCANNER UNIT
Usually the scanner unit is installed in a high place. Consequently, a slight mishap can
result in a serious accident. Note the following precautions when repairing and inspect-
ing the scanner unit.
1. Set the display POWER switch and the main switch for
distributing
power to the radar
to OFF so that there is no danger of the antenna rotating during repair and inspection
In addition, before starting
any repairs or inspection, post a sign on the display unit
indicating that maintenance is in progress
so that there is no danger of a third party
accidentally setting these switches to on.
2. When repairing or inspecting the scanner unit wear a safety harness and
provide a
secure platform so that there is no danger of falling even when the vessel lists o r when
there is an unexpected incident such as an earthquake.
ELECTROMAGNETIC
RADIATION
DO NOT approach the antenna while it is
transmitting.
NEVER get within 15 meters of
the antennaradiating surface while the antenna is transmitting. In addition, at inspection,
NEVER look into the waveguide during
transmission.
CRT
MAINTENANCE
The CRT used in this radar has a high vacuum and it is extremely
dangerous
if it
is
damaged. Observe the following precautions.
1.
Never rest anything on the CRT.
2. Never press on the front display surface of the CRT.
3. Never drop the display unit.
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