Term
| T9A01 What is a beam antenna? |
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Definition
| An antenna that concentrates signals in one direction |
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Term
| T9A02 Which of the following is true regarding vertical antennas? |
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Definition
| The electric field is perpendicular to the Earth |
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Term
| T9A03 Which of the following describes a simple dipole mounted so the conductor is parallel to the Earth's surface? |
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Definition
| A horizontally polarized antenna |
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Term
| T9A04 What is a disadvantage of the "rubber duck" antenna supplied with most handheld radio transceivers? |
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Definition
| It does not transmit or receive as effectively as a full-sized antenna |
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Term
| T9A05 How would you change a dipole antenna to make it resonant on a higher frequency? |
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Definition
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Term
| T9A06 What type of antennas are the quad, Yagi, and dish? |
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Definition
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Term
| T9A07 What is a good reason not to use a "rubber duck" antenna inside your car? |
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Definition
| Signals can be significantly weaker than when it is outside of the vehicle |
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Term
| T9A08 What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz? |
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Definition
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Term
| T9A09 What is the approximate length, in inches, of a 6 meter 1/2-wavelength wire dipole antenna? |
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Definition
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Term
| T9A10 In which direction is the radiation strongest from a half-wave dipole antenna in free space? |
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Definition
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Term
| T9A11 What is meant by the gain of an antenna? |
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Definition
| The increase in signal strength in a specified direction when compared to a reference antenna |
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Term
| T9B01 Why is it important to have a low SWR in an antenna system that uses coaxial cable feedline? |
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Definition
| To allow the efficient transfer of power and reduce losses |
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Term
| T9B02 What is the impedance of the most commonly used coaxial cable in typical amateur radio installations? |
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Definition
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Term
| T9B03 Why is coaxial cable used more often than any other feedline for amateur radio antenna systems? |
|
Definition
| It is easy to use and requires few special installation considerations |
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Term
| T9B04 What does an antenna tuner do? |
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Definition
| It matches the antenna system impedance to the transceiver's output impedance |
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Term
| T9B05 What generally happens as the frequency of a signal passing through coaxial cable is increased? |
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Definition
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Term
| T9B06 Which of the following connectors is most suitable for frequencies above 400 MHz? |
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Definition
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Term
| T9B07 Which of the following is true of PL-259 type coax connectors? |
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Definition
| The are commonly used at HF frequencies |
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Term
| T9B08 Why should coax connectors exposed to the weather be sealed against water intrusion? |
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Definition
| To prevent an increase in feedline loss |
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Term
| T9B09 What might cause erratic changes in SWR readings? |
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Definition
| A loose connection in an antenna or a feedline |
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Term
| T9B10 What electrical difference exists between the smaller RG-58 and larger RG-8 coaxial cables? |
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Definition
| RG-8 cable has less loss at a given frequency |
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Term
| T9B11 Which of the following types of feedline has the lowest loss at VHF and UHF? |
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Definition
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