Everything You Need to Know about FM Broadcast Antenna

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Everything You Need to Know about FM Broadcast
Antenna
Antennas come in different shapes and sizes.
Every antenna performs differently from another.
Choosing the right kind of antenna is very
important for gaining better performance. FM
Broadcast Antennas help to receive high-quality
FM broadcasts. They also help to receive strong
indoor signals. Antennas designed with bands
between 88 MHz and 108 MHz are good for
receiving the FM broadcast. They also give the
most effective FM reception. In this blog, we
will discuss everything related to FM broadcast
antenna and its features, benefits, and how it
works. Basics of Dipole antenna Before we discuss
the different features of a dipole antenna, it is
necessary to learn its basics. Dipole Antennas
contain two parts or
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poles. In a half-wave dipole, each leg is an
electrical quarter wavelength long. The length
of the dipole is determined by the frequency
operation. FM broadcast band extends from 87.5
MHz to 108 MHz. Coaxial cable is used for a
balun in this type of antenna. The outer shield
is attached to the earth and the antenna is
balanced. In a dipole antenna, the inner
conductor of the coax is attached to one leg of
the dipole and the outer conductor of the coax is
connected to the antennas other leg. FM
interference Problems of FM interference occur
often when the distance between the transmitting
and receiving antenna is increased. Tropospheric
scatter causes parts of the FM transmissions to
be retracted towards the earth at some distance
within a normal line of sight. This phenomenon
occurs when a temperature inversion is located in
the FM broadcast signal path. These signal
refractions create FM reception. They can also
disrupt the reception of FM broadcast
transmission. Obstructions to FM broadcast
signals can range from small hills and buildings
to mountains. The resultant effects could be
partial absorption that reduces received signal
strength. Multipath interference distorts the FM
signals resulting in low-fidelity
reception. Steps to develop FM dipole antenna It
is very simple to design an FM dipole antenna.
You will need some basic accessories to make
this antenna such as
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• Wrap to secure the center of the diploe and
  prevent the flex from opening out
• Twin flex of old speaker
• String or twine to secure the ends of the dipole
  to fixing points
• Connectors connected to the coaxial cable
• One of the major benefits of using mains flex is
  that it is used as a feeder for radio frequency
  signals. This wire is a close approximation to
  75 ohms or a twin or open wire feeder. FM dipole
  antenna can be made with the help of a cheap
  speaker wire.
• To design a VHF FM dipole antenna, the cable must
  have the two insulated wires split back away
  from one another and opened out. The next step
  is to secure the center to prevent the cable to
  open out. You can use a wrap that is available
  in most electronics components stockiest. You
  can use the length of the wire as the feeder for
  the antenna.
• You must keep the length of the antenna at about
  150 cm. Then you can knot the ends of the wire
  to attach it to some string. The knotting of the
  wire adds some inductance to the wire ends.
• While installing the antenna in a roof space,
  keep it away from all the objects made of metal.
  The ends of the antenna are more sensitive to
  metal objects.
• Common types of outdoor FM broadcast antennas
• Now, we will discuss the common types of FM
  broadcast antennas in this section.

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• Crossed dipole or Turnstile
• This Circular Polarization Antenna provides an
  omnidirectional receive pattern. It has low gain
  in all the planes.
• Unidirectional dipole
• The next type of outdoor FM Broadcast Antenna is
  a unidirectional dipole. It is a large dipole
  with two elements and more gain than the
• common indoor twin lead dipole. This dipole
  antenna emits the signals in one direction.
• Multi-element array
• This is a kind of unidirectional antenna that can
  receive distant stations
• because of high gain. This gain is directional
  and needs an antenna to be rotated.
• Types of Indoor FM antennas
• Many urban and near-suburban areas cannot install
  an outdoor
• antenna. In these areas, an indoor FM antenna can
  be installed. Let us have a look at the kinds of
  Indoor FM antennas
• Amplified indoor antenna
• Amplified antenna designs have inherent tradeoffs
  in signal-to-noise
• and other negative RF attributes.
• Unamplified indoor antenna
• The unamplified indoor antenna has two basic
  antenna configurations.
• ½ wave vertical
• This vertical antenna has a high gain for an
  indoor antenna. It provides
• high-quality FM reception in urban areas.

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• Bidirectional dipole
• These Directional Antennas are commonly used
  indoor FM antennas.
• Single, dipole design and ½ waves exist as an
  industry gain reference for most FM broadcast
  band antennas. It gives signals from all
  directions.
• Benefits of using FM broadcast antenna
• We discussed the different types of Horizontally
  Polarized Antennas. Now, let us have a look at
  the benefits of Omni directional Antennas.
• FM broadcast antenna is very easy to install and
  set up in urban areas and stations.
• These Circular polarized Antennas never rust or
  get damaged due to sun rays, winds, water, or
  snow. They work for a long time and give better
  performance than normal antennas.
• Vertically Polarized Antennas give high-quality
  FM broadcasts.
• It is easy to use these antennas without any
  professional guidance.
• Yagi Antenna gives strong signals in all areas
  and directions.
• These antennas are cost-effective and give
  stronger signals than other types of antennas.
• One can design an FM broadcast antenna with the
  help of some basic materials.
• Read more Advantages and Disadvantages of Yagi
  Antenna
• Where to find the best quality FM broadcast
  antenna?
• Today, it is easy to get the best quality FM
  broadcast antennas from
• online sites. You can check the official site of
  FM Broadcast Antennas Manufacturer on Google
  engine. Some companies provide a long-term
  warranty on FM broadcast antennae to their
  regular customers.