XLi Time & Frequency System 21
XLi-man, Issue 8, 6/17/2008, Rev. H
2
5
1
SSSSSSSSSSSS SSSSSSSSSS SSSSSSS S SSS S SSSSS S
ring and a key tab and groove. Neither the O-ring or key are critical to the antenna operation. The O-ring
makes for a more weather proof seal for the antenna connector. The key ensures that the housing
always connects in the same orientation.
The pipe that is shown disconnected above, also acts as a protective housing for the optional antenna
preamplifier. A preamplifier should be connected to the antenna assembly if the distance between the
antenna and receiver is greater than 150 ft. The preamplifier connects to the TNC connector on the
antenna housing by a three inch TNC to TNC adapter cable. The open end of the preamplifier is then
connected signal cable from the receiver connects to the
A 50 ft cable is provided with each antenna assembly. If the distance between the antenna assembly and
receiver is greater than 50 ft, replace the 50 ft cable with a longer cable as opposed to adding an
extension to the 50 ft cable.
To connect the antenna cable to the antenna assembly, do the following:
1. Separate the antenna by loosening the four captive antenna housing screws.
2. Pass the TNC end of the receiver signal cable through the support pipe and lower half of
the antenna assembly and connect it to the antenna signal connector.
a. If a preamplifier is to be used, connect the three inch preamplifier adapter cable to
the antenna signal connector.
b. Connect the preamplifier to the adapter cable.
c. Connect the receiver signal cable to the preamplifier.
3. Reconnect the antenna by tightening the four captive antenna housing screws. Make
sure that the O-Ring is correctly sitting in its groove and that the Key tab and groove are engaged.
GPS Signal Strength Requirements
Refer to Figure 4: GPS Signal Strength Requirements.The required external gain at the GPS receiver’s
ANTENNA connector is between 20 and 36 dB.
For example, the Symmetricom GPS antenna provides approximately 41 dB of gain. If one subtracts the
16-21 dB loss of the 150 foot RG-59 coax antenna cable supplied by Symmetricom, the external gain
reaching the ANTENNA connector is between 20 and 36 dB, which meets the requirement. Abide by the
minimum input gain requirements when using other cable types and GPS antennas.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
To Next Page
Loading...
Need help?
General
