Motorola Spectrum Series, Руководство по установке

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Mobile Antenna Installation 13
6. Use the adjustment range of the whip in the adaptor in order to minimize the VSWR.
7. Insert the shorter part of the allen wrench into the screw and tighten the set screw at tight as
yo can by hand. If a torque wrench is available, tighten set screw to a torque of 25 – 30 inch-
lbs.
A simple table for converting the ratio of forward power and reflected power to VSWR is given below:
Example: If the forward power (Pfwd) is measured as 100 watts and the reflected power (Pref) is 3
watts, calculate Pfwd/Pref = 33.3. Since 33.3 is between 25 and 58.8 m, the chart above indicated
that the VSWR is less than 1.5 : 1.
Table 3
Pfwd/Pref VSWR
440.6 1.1 : 1
58.8 1.3 : 1
25.0 1.5 : 1
14.9 1.7 : 1
10.4 1.9 : 1
7.9 2.1 : 1