Hints: In addition to the meter, we recommend you use the following items to help you measure field strength.CB and amateur radio systems work best when the antenna systems impedance matches the transmitters output impedance as closely as possible.
The meters standing wave ratio (SWR) function helps you trim your antenna to the precise length you need for the maximum transmitted power. The meters field strength function helps you position your antenna for the best coverage and determine the effectiveness of changes you make to your antenna, antenna cable, and transmitter. With this information, you can adjust the length of your antenna or antenna cable so your antenna and radio combination can. To connect this meter to your CB or amateur radio and your antenna, you need coaxial cable ( 50 ohm such as rg-8x) with a PL-259 connector on both ends. The cable must reach from the back of the meter to your radios antenna jack. Follow these steps to connect the meter to your radio and antenna. Then disconnect the antenna from the radio and plug it into ANTENNA on the back of the meter. If you transmit on one channel more often then any other, select that channel. If you transmit on several channels, choose a frequency in the middle of the range of channels you use. For example, if you transmit on all 40 CB channels, choose Channel 20, because it is midway between Channel 1 and Channel 40.) If you use a CB that has sideboard modes (SSB), do not select any of these modes. Use only AM for SWR measurements). If you have an amateur radio, select the continuous wave (CW) or tuning mode to check the SWR. The figure shown between the upper and lower scales on the meter ( REF POWER) indicates the percentage of power that is wasted through reflection of the signal from the antenna back into the antenna cable. However, 96 of the radio power is more than enough for almost all applications. The information below will help you interpret the readings you get. There are several ways to improve the SWR of your radioantenna combination. If the manufacturer recommends a 50-ohm cable, do not substitute another type that has a different impedance. The angle and the base arrangement can affect the SWR reading. A change of as little as 18 inch can make a measurable difference. You can use these measurements to map the transmitting direction and coverage pattern of your antenna, or to compare your radio and antennas efficiency before and after an adjustment. You do not need to connect the meter to the antenna or the radio to measure field strength. For an accurate measurement, you will need to map the site around your antenna. Then, while someone presses the radios transmit key, you will need to walk around the site around your antenna with the meter, marking the readings you see.
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