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STANDING WAVE RATIO CHART
The ideal standing wave ratio (SWR) reading is a 1:1 ratio, or a meter reading of 1 on
the SWR meter’s top scale (which you can usually get only in laboratory test condi-
tions). A 1.5:1 to 2:1 SWR ratio is excellent for most mobile CB antenna applications.
This chart explains the different readings you might see.
Note: Prolonged exposure to the elements (salt spray, humidity, corrosion, and so
on) or vehicle vibration can cause degradation in antenna performance and a rise in
the SWR meter’s normal reading. Once a month, or anytime the SWR reading is
greater than 3, check the condition of the antenna and its coaxial cable, RF electrical
connections, and so on.
Standing Wave Ratio Chart
Ratios
Rating
Description
1:1 to 1.5:1
Superior
Perfect match between the antenna/cable system and
the CB’s RF output power.
1.5:1 to 2:1
Excellent
The antenna/cable system are an outstanding match
with this CB transmitter’s RF output power. Ideal for
most CB installations.
2:1 to 3:1
Good
The antenna/cable system with this CB transmitter will
perform to specifications under most normal conditions.
Higher
than 3.1
Inefficient
Requires inspection of antenna system’s mounting
hardware or ground, or adjustment/replacement.
21-1573.fm Page 11 Thursday, August 5, 1999 9:22 AM