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Working with Different Antennas
All of City Theatrical’s SHoW DMX Neo Transceivers and Receivers are provided with omni-
directional antennas as standard equipment when shipped from the factory. This is a good
general purpose choice when nothing else is known about the application the equipment will be
used for; the antennas provide adequate power and the omni-directional pattern adapts well to a
wide variety of environments. But specialized antennas can enhance the performance of a
wireless system in a variety of ways if the environmental conditions are known, or if particular
problems need to be overcome. CTI offers a range of approved specialized antennas that can
enhance system performance in a range of applications.
Antenna Approval
2.4GHz antennas are available on the general market and are often sold without caveat or
restriction, however federal authorities require antennas used with transmitting radios to be
approved for the specific radio system they are used with. Beware of unapproved after-market
antennas that may push your system out of compliance and may be illegal.
The CTI antennas have all been tested and approved for use in both the US and Canada with
CTI’s SHoW DMX Neo family, including all of the CTI wireless products that utilize built-in
SHoW DMX technology.
CTI antennas can also be used in EU countries and locations that adhere to CE rules, providing
some conditions are met. Notably, antennas rated over 5dBi require attenuators in CE
applications. Extension cables provide inherent attenuation, and may be considered as part of
the attenuation needed. For example, an 8dBi panel used in the EU would require a 3dBi
attenuator, or you could use a 5-meter long CTI LMR 195 cable (CTI Antenna extension cables
are made to order, contact City Theatrical for details).
Note that the 5636 14dBi Yagi Antenna has special requirements for FCC / IC use, and may not
be used in CE countries; see the Antennas section (page
Power Ratings
CTI’s antennas are rated in decibels or “dBi”. The dBi rating describes the gain of the antenna
(how powerful it is), with higher numbers indicating greater power. 8dBi is more powerful than
5dBi.
Range
SHoW DMX Neo systems used with the CTI 5630 7” Omni-Directional Antenna have a typical
range of 100 meters indoors, 500 meters outdoors. Actual range will vary with the installation
and environment. Range can be greatly increased with directional antennas, as discussed
below.
Omni-Directional Antennas
Omni-Directional antennas produce a pattern of radio waves that looks almost like a donut
around the antenna axis. These antennas basically broadcast in a donut shaped pattern that
radiates 360° from the antenna, so their available energy is spread out over a wide area.
The CTI 5630 7” Omni-Directional Antenna provided with most SHoW DMX Neo models is a
typical small omni-directional antenna. The 5730 2dBi antenna provided with SHoW DMX
SHoW Baby is similar, with lower gain and a smaller size.
