- 1). Connect the SWR meter to the aerial and the CB radio. The SWR meter will be supplied with a small piece of coaxial cable. Connect one side of this cable to the "TRANS" terminal on the SWR meter and the other side to the antenna output on the CB radio. Connect the coaxial cable from the aerial to the "ANT" terminal on the SWR meter.
- 2). Calibrate the SWR meter. Switch the SWR meter to the "CAL" mode of operation. Turn on the CB radio and transmit a signal. While transmitting, adjust the "CALIBRATION" knob so that the needle on the meter is aligned with the "CAL" mark.
- 3). Measure the SWR. Switch the SWR meter to "SWR" mode. Transmit a signal using the CB radio. The needle on the SWR meter will be deflected and show the measured value. If the SWR value is below 3, no further work is needed. A SWR value above 3 indicates a high reflected power.
- 4). Reduce the SWR by adjusting the aerial or the coaxial cable. Every CB radio aerial basically consists of an inner and an outer metallic pole. The inner pole is free to move within the outer pole, changing the length of the antenna, and different positions will lead to different SWR values. The SWR should be measured for a variety of different inner pole positions. The variation of this parameter should allow one to obtain a SWR of less than 3. A possible problem leading to high SWR values is poorly connected coaxial terminations. Ensure that each coaxial connector has good contact with the center pin of the coaxial cable and that the grounding sheath makes good contact with the outer grounding shell of the connector.
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