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When first setting up a radio or moving a radio to a new, permanent location, its antenna needs to be tuned. Learning how to tune an antenna entails lengthening or shortening the antenna so that, for the radio's specific frequency, it is working as efficiently as possible. In order to tune an antenna, a radio needs to be hooked up to an SWR (standing wave ratio) meter using coaxial cables. This guide will teach you how to test an antenna's efficiency using an SWR meter, and how to tune your antenna accordingly.
Steps
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1Go to an open area free from buildings, trees, radio towers, or other structures.
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2Put your radio and antenna in the positions in which you will use them.
- For a CB radio, put the radio in the car and the antenna on the body of the vehicle. For a portable radio, move away from any vehicle and stand alone with the radio.
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3Remove any connections between the antenna and the radio.
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4Attach the radio to the transmitter socket on the SWR meter using a coaxial cable.
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5Attach the antenna to the antenna socket on the SWR meter using a coaxial cable.
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6Set the radio to minimum power and to FM or CW mode.
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7Tune to the lowest band available. On a CB radio, tune to Channel 1.
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8Transmit from the radio or, on a CB radio, press the talk button.
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9Observe and record the SWR reading. It should be in the form of a ratio, e.g. 2.2:1.
- Repeat Steps 6-8 for the highest band available, or, on a CB radio, Channel 40.
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10Determine from the difference between the SWR readings whether your antenna is too short or too long.
- If the SWR reading on the lowest band, or Channel 1, is greater, your antenna is too short. If the SWR reading on the highest band, or Channel 40, is greater, your antenna is too long.
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11Adjust your antenna accordingly, and very slightly.
- For most antennas, this means manually lengthening or shortening the antenna. For a wire antenna, clip off a bit of the end to shorten it (if you have a wire antenna that is already too short, you will need to get a new antenna).
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12Repeat Steps 7-10, tweaking your antenna gradually until the SWR readings on the lowest and highest bands, or Channel 1 and Channel 40, are identical.
Community Q&A
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QuestionCan I use an SWR meter for a digital TV antenna?Imhungry ImhungryCommunity AnswerNo, there are digital tuning meters for tuning signals, but the cheapest I have seen is about $200 and most are over $1000. For $40 you can buy a converter box and use the built-in tuning meter for aiming your antenna, but it isn't battery powered and portable.
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QuestionHow do I find the built in digital antenna on an LG TV?Community AnswerIt will be on the back of the TV and will usually be a metal bolt with a white center and hole through, also known as coax. It also may be labeled ANT or Antenna.
Warnings
- Do not hold the antenna while tuning.⧼thumbs_response⧽
Things You'll Need
- Radio
- Antenna
- SWR meter
- Two lengths of coaxial cable