What is the impedance of a long wire antenna?
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What is the impedance of a long wire antenna?
Impedance is highest on the lowest band. Note it is 6850 ohms on 80 meters, decreasing to 1360 ohms on ten meters. This is because more and more half waves are being fed from one feedpoint with increasing frequency….Counterpoises.
Advantages | Disadvantages |
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inexpensive | require a tuner or matching system |
What is the impedance of an end fed wire antenna?
The feeding point of a multiband End Fed antenna is practically a wide band impedance transformer. This means that the end fed wire antenna, which has a very high impedance of around 2500 Ohm, is transformed to an impedance of 50 Ohm. This impedance suits best to most tranceivers.
What is the radiation pattern of a long wire antenna?
Therefore, the radiation pattern of this type of antenna is unidirectional, as waves follow only forward path. Unlike the resonant type of antenna, here the length of the wire is inversely proportional to the frequency.
How long should a counterpoise wire be?
20-30 feet
Length of counterpoise should be a minimum of 20-30 feet but longer is better. If possible run the counterpoise above ground away from or perpendicular to the antenna wire and do not ground the counterpoise at the unun.
Is a long wire antenna directional?
In fact the definition of a long wire antenna is one that is a wavelength of more in length. In fact some long wire antennas are many wavelengths long. With antennas of this length, the radiation directional pattern shows lobes that align more with the axis of the antenna as the length in wavelengths increases.
What happens if antenna is too long?
If you use an antenna which is “too long” or “Too short” for the frequency, it will not resonate, HOWEVER if you use an “Antenna tuner” you can usually electrically tune the antenna to cancel out the reactance and make the antenna resonate at the frequency in use.