POWER LOSS AT VARIOUS SWR
READINGS AND RESIDUAL POWER

Compliments of Firestik® Antenna Company Technical Support Team

Copyright © 1996 Firestik® Antenna Company

SWR (Standing Wave Ratio) affects the power output of your radio. The following table shows the effect of SWR for a transmitter with 4 watts of transmitted power.

* ERP = Percentage of Effective Radiated Power
SWR READING % OF LOSS ERP* WATTS AVAILABLE
1.0:1 0.0% 100.0% 4.00
1.1:1 0.2% 99.8% 3.99
1.2:1 0.8% 99.2% 3.97
1.3:1 1.7% 98.3% 3.93
1.4:1 2.8% 97.2% 3.89
1.5:1 4.0% 96.0% 3.84
1.6:1 5.3% 94.7% 3.79
1.7:1 6.7% 93.3% 3.73
1.8:1 8.2% 91.8% 3.67
2.0:1 11.1% 88.9% 3.56
2.2:1 14.1% 85.9% 3.44
2.4:1 17.0% 83.0% 3.32
2.6:1 19.8% 80.2% 3.21
3.0:1 25.0% 75.0% 3.00
4.0:1 36.0% 64.0% 2.56
5.0:1 44.4% 55.6% 2.22
6.0:1 51.0% 49.0% 1.96
7.0:1 56.3% 43.8% 1.75
8.0:1 60.5% 39.5% 1.58
9.0:1 64.0% 36.0% 1.44
10.0:1 66.9% 33.1% 1.32


Firestik Antenna Company - 2614 E Adams St - Phoenix, AZ 85034 - (Tel) 602-273-7151 - www.firestik.com

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