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.
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| Standing Wave Ratio Chart |
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Ratios | Rating | Description |
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1:1 to 1.5:1 | Superior | Perfect match between the antenna/cable system and |
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| the CB’s RF output power. |
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1.5:1 to 2:1 | Excellent | The antenna/cable system are an outstanding match |
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| with this CB transmitter’s RF output power. Ideal for |
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| most CB installations. |
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2:1 to 3:1 | Good | The antenna/cable system with this CB transmitter will |
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| perform to specifications under most normal conditions. |
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Higher | Inefficient | Requires inspection of antenna system’s mounting |
than 3.1 |
| hardware or ground, or adjustment/replacement. |
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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.
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