How to Measure the RF Output of an Antenna
- 1). Disconnect your antenna's coax cable from the back of your scanner or CB radio. Plug the disconnected coax end into the "ANT" port on your SWR meter.
- 2). Connect the SWR/Power meter to your radio using a coax cable.
- 3). Reference your radio's output power specifications and then set the SWR/Power meter's wattage to in range. For example, if the radio is 4 watts, you would set the meter to the 10 watt range. But if the radio is 50 watts, you'd set it to the 100 watt range.
- 4). Set the SWR/Power meter to the "FWD Pow" or "Forward Power" setting to find out how much power is sent to the antenna from the radio.
- 5). Set the SWR/Power meter to the "REF POW" or "Reflected Power" position to see how much power is lost through the antenna.
- 6). Subtract the amount of reflected, or lost, power from the amount of forward power to find out how much power your antenna is transmitting.
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