JRC JLR-21 Instruction Manual page 7

When used in other than ships, it may not satisfy the desired performance and
functionality. Because this product is designed to be installed for the ship.
Heaving function of this product is intended to measure swinging in the vertical
direction of the ship.
So, it is not possible to measure something (wave height etc.) other than
swinging in the vertical direction of the ship.
It is not possible to measure also the tsunami.
When you install JLR-21/31 in retractable mast, please observe the following
strictly.
① An unusual vibration or an unusual shock should not occur.
② When the mast has retracted, please stop use. Because normal operation
cannot be performed.
③ A difference should not occur in the position by retracting.
Install the sensor where there are no obstacles, in order to ensure that GPS
signals can be directly received from satellites without interference or
reflection of signals from surrounding objects.
Whenever possible, select a place with the following characteristics.
1. An open space, which allows uniform reception of satellite
signals.
2. Far away from any high power transmission antennas.
3. Outside radar beams.
4. Away from the INMARSAT antenna by at least 5 meters and
outside the INMARSAT beam.
5. Away from the antenna of a VHF transmitter and a direction
finder by at least 3 meters.
6. Away from a Magnetic Compass by at least 1 meter.
7. 3 meters or more away from amateur radio antennas.
If it is difficult to find an ideal site, select a place temporarily and install the
equipment. Conduct a test to make sure that the proper performance can be
obtained and then fix the equipment in position. If it is installed at an improper
place, reception accuracy may be impaired.
CAUTION
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