GlobalTime NTP Products
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antenna, but other block will influence the signal significantly. In fact, only a book above the
antenna can completely block out the satellite signal.
Second, antenna installation should be lower than the lightning rod or other constructions
that can attract thunderstroke and the installation location should better be 10-15 meters
away from them. GPS antenna itself is rarely struck by thunder blot but is often damaged by
the stong induced electric field resulted from the stuck buildings (the lightning rod, tower, etc)
around. In this circumstance, we should install the arrester in the cable. Normally the
arrester
will be installed at the position where the cable goes through the wall. By this, the
arrester can be well earthed. The arrester should also be installed between the feeder and
the equipment. Then lead the grounding wire from the arrester and connect it to the earth.
The earth resistance should be under 4 ohm and must be firmly connected to ensure the
reliable discharge by lightning.
Sometimes the antenna can be installed outside the window, but the building must be
located in the open fields with no corner. In this way, it can receive at least half of the
satellite signal. But as a long-term using equipment , it is recommended that the antenna is
installed in high places, while the outside installation can be only adopted as a temporary
test.
The high-power microwave transmitting of the same band can not be around where the GPS
antenna is installed. In addition, we should try to avoid the GPS antenna from the direct
irradiation of high-power electromagnetic radiation.
If the length of the feeder is less than 100 meters, the antenna and equipment can be
directly connected; between 100 meters to 200 meters, one more line amplifier is needed;
ranging from 200 meters to 300 meters, two more amplifiers are needed. If you need longer
feeder links, please contact us, GlobalTime Electronic Co., Ltd. We will provide the special
program to you. The feeder usually adopt 1 / 2 inch RF cable whose loss is 12.8dB/100m
from the United States Andrew's.
When setting up the feeder:
1. Do not bend too much, because it will result in a broken feeder conductor.
2. When we connect the feeder into the interior, it should be bent into U-shape to prevent
t water
from flowing backward.
You can use GPS signal transponder to lead the signal to the interior. Generally speaking,
GPS signals can be well received within 5 m of the transponder antenna. Because of the
