JJ wrote:
Len Over 21 wrote:
Incorrect. The word "dipole" refers to anything with two elements
and a
polarity. [a "monopole" is a single element with no polarity]
A dipole ANTENNA refers to a wire type having two elements of wires,
balanced-fed from the center with RF voltage in opposition.
The length of this dipole antenna may be ANY length, from
near-infinitesimal
(fractional wavelength) to many wavelengths.
The radiation pattern of the dipole antenna will vary based on many
factors:
length relative to wavelength, distance above ground or other
imperfect
conductor being the two most affecting patterns.
Len is correct, dipole simply means two separate elements (di means
two). A dipole of a certain length will be a half wavelength at xx
frequency, a quarter wavelength at yy frequency and a full wavelength
at zz frequency and so on.
Sure enough. a dipole can be anything at all as long as it has those
two separate elements.
But do you think that is what they meant? Is the test going to ask you
to design a dipole that won't work very well?
If I saw that question on a test,(design a quarter wave dipole) I would
assume it was a trick question.
That a quarter length dipole can exist is in no doubt. Most of them are
a quarter length at some frequency. But this was a mistake, and not an
uncommon one. Its okay, people do that once in a while! 8^)
- Mike KB3EIA -
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