jotron 103660, Руководство оператора и инструкция по установке

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Doc. No.: 103839 Rev. A
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Page 42 of 104
8.2.1 GPS antenna
The table below gives recommendations on cables that can be used for the GPS antenna connections:
Type Attenuation @1.5 GHz (dB/100m) Remark
RG58
90 Default for use if length< 20 m and antenna = SANAV SA-200
RG214
35 Cable with lower loss
RG225
30 Cable with even lower loss
For optimum performance of the transponder approxi10dB gain should be available when the cable
attenuation has been subtracted from the GPS antenna preamplifier gain.
8.2.2 VHF antenna
The table below shows the attenuation on the VHF frequencies with different cable types:
Cable Type Attenuation @150 MHz (dB/100m) Diameter (mm) Weight (kg/100m)
RG214
7 10,8 18,5
RG225
8 10,9 23,3
Example: A RG 214 cable with length of 40 meters will have an attenuation of 2,8 dB.
Please keep the cables as short as possible, and be aware that 3 dB losses mean only half the output power. If you
have a transmitter delivering 12,5 W, and you have 3 dB losses in the cable, only 6,25 Watts will be at the antenna.
8.2.3 Cable between Transponder and Display Unit
The cable connecting the Transponder and the Display Unit has specially designed connectors on each end for
waterproofing. The cable itself is a standard CAT-5 network cable
In order to ease wiring and installation, an optional cable is available with one end open, delivered with a small kit
for post wiring assembly.
If the specified cable type is not used, the splash proofing of the unit is seriously degraded and the warranty is void
if used in humid environment.
Figure 8-9 Connection cable for interconnection between the Transponder and the Display Unit
If the units are mounted indoors in a warm dry environment without any need
for water tightness, a standard CAT-5 or CAT-6 network cable may be used
between the Transponder and the Display unit