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Multiverse Transmitter Theory of Operation, Continued
Here are some questions to consider when planning your radio setup:
1. How many universes will you broadcast from each transmitter?
2. Exactly which universes will you broadcast?
3. What is the status of the spectrum around you? This may influence your choice of
radio frequencies on which to broadcast, which portion of the chosen band on which to
broadcast, or even which model of Multiverse Transmitter to choose.
4. What is the approximate distance between your Multiverse Transmitter and your
Multiverse Nodes?
5.
Is your show’s cueing relatively simple, such as conventional or LED fixtures and
moving lights, or do you have direct view LED chases?
6. Are specialized antennas needed? Panel and Yagi antennas can help to overcome
challenges related to fidelity or distance while keeping unneeded radio energy away
from other systems in the venue.
Our Technical Services team is always available to assist you in making these setup decisions.
Call 201-549-1160 or email
Understanding the Radio Spectrum Around You
Radio waves are not visible and it is often not possible to understand the amount of radio activity
around you without doing some research and testing, but it is important to the quality of your
broadcast to do so. One way is to ask about and to be aware of other radio gear on site that is in
the 900MHz band. You can find this by searching carefully for broadcast devices and antennas,
and by asking your colleagues if they are using any radio gear in your area of the spectrum.
Beyond that, we highly recommend that you invest in some basic portable spectrum analysis
gear. Useful gear includes:
•
Wi-Spy with Chanalyzer from Metageek for 2.4GHz spectrum analysis
https://www.metageek.com/products/wi-spy/
•
RF Explorer from Seeed Studio for 900MHz and 2.4GHz spectrum analysis
https://www.seeedstudio.com/spectrum-analyzers-c-876/RF-Explorer-ISM-Combo-p-
1092.html
If your analysis reveals a lot of radio activity in one particular area of the spectrum, by using the
“Band” selection of the SHoW ID (fourth digit of the SHoW ID) you can direct your broadcast to a
quieter area of the spectrum. If all areas seem crowded you can choose either full spectrum
hopping or adaptive hopping. See the SHoW ID chart in Table 1 on page 7.
Choosing a SHoW ID
SHoW ID is a proprietary system developed by City Theatrical to give wireless DMX users the
ability to optimize their systems to meet the conditions of the environment in which they are
operating. Using the knowledge and information you have gathered so far, you can now choose a
SHoW ID, which is simply a descriptive number that represents a combination of four elements:
•
The radio frequency
•
The data rate (which determines the number of universes you can broadcast)
•
The section of the wireless band where the radio frequency hopping will occur
•
The hopping pattern.
These choices combine to form a number that sets the basic broadcast parameters of the system.
Let’s take a closer look at the SHoW ID numbering system:
Table 1: Selecting Your Multiverse SHoW ID