Paradise Datacom RA 5785, Руководство по эксплуатации

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Operations Manual, HPA3, Mini Compact Outdoor SSPA 208143 REV - 45
4.5 Typical System Configuration
This section shows the Compact Outdoor SSPB in a common system application.
Figure
4-3 shows the Compact Outdoor used with a Paradise Datacom Evolution Series PD25
modem.
4.6 IFL Cable Considerations
Consideration should be given to using a high quality IFL between the indoor equipment and
Compact Outdoor SSPB. The system designer must always consider the total cable loss for a
given length and also the implications of the slope of attenuation across the 950 to 1450 MHz
bandwidth.
Table 4-3 gives the approximate attenuation vs. frequency for a variety of cable
types.
It is recommended to use a quality grade of 50 ohm cable such as Belden 9913, 9914, or
7733. Check the manufacturer’s technical data to make sure that the insulation is sufficient for
the particular installation including the cable’s temperature range. Also make sure the coaxial
connector from the IFL cable to the Compact Outdoor input is wrapped with a weather sealing
tape to prevent water intrusion into the coaxial cable.
PARADISE
DATACOM
IFL Cable
Indoor Equipment Outdoor Equipment
IF: 950 - 1450 MHz (-30 to -20 dBm ) at Compact Outdoor SSPB
Ref: 10 MHz (-5 dBm to +5 dBm) at Compact Outdoor SSPB
Figure 4-3: Mini Compact Outdoor SSPB with PD25 Evolution Modem
RS485 M&C
Cable Type Center
Conductor DC
Resistance per
1000 ft.
Outer
Diameter
(inches)
Attenuation at
950 MHz
dB per 100 ft.
Attenuation at
1450 MHz
dB per 100 ft.
Slope across
band for 100
ft. cable (dB)
Slope across
band for 300
ft. cable (dB)
RG-214 1.7 .425 7.8 11.3 3.5 10.5
Belden 8214 1.2 .403 6.8 9.2 2.4 7.2
Belden 7733 .9 .355 5.8 8.3 2.5 7.5
Belden 9914 1.2 .403 4.5 6.3 1.8 5.4
Belden 9913 .9 .403 4.2 5.6 1.4 4.2
Table 4-3: Common Coaxial Cable Characteristics