The primary method of isolating multiple RC4 universes is our Private System IDentities. There's an article about this on our website at https://rc4wireless.com/system-ids/.
In short, each system ID is a unique key. Multiple devices configured to use the same key become a Virtual Private Network (VPN). You can run multiple universes by configuring groups of devices on separate and unique System IDentities.
To further improve performance, different portions of the RF spectrum are used for separate universes. The method for accomplishing this is different for our 2.4GHz and 900MHz systems. In the 2.4GHz band we use Direct Sequence Spread Spectrum (DSSS), which divides the band into 12 channels. When an RC4Magic transmitter powers up, it scans the band and finds the quietest channel to use. In an ideal world where nothing else is using the 2.4GHz band at all, you could run 12 completely independent RC4Magic DMX universes and they will automatically distribute themselves across the available channels.
The RC4Magic-900 system uses Frequency Hopping Spread Spectrum (FHSS). In this case, the 900MHz band is divided into 64 channels, of which 25 are needed for a single universe. That selection of channels is what we call the Channel Mask, or sometimes the Frequency Mask. The selected RC4 Private System IDentity is used to generate a unique hopping sequence. Thus, even if two different universes are configured to use the same 25 radio channels, the pattern used to distribute data across those channels is different. Although there will occasionally be a data collision when more than one system arbitrarily and very briefly lands on the same RF channel at the same time, digital error detection and correction make these events unnoticeable. Even so, we generally do not run multiple systems on exactly the same Frequency Mask, we create unique sets of channels -- different Frequency Masks. There is a default Frequency Mask for each ID to make configuration simple, and we also provide a few additional ones, for a total of 8 ready-made Frequency Masks.
In short, each system ID is a unique key. Multiple devices configured to use the same key become a Virtual Private Network (VPN). You can run multiple universes by configuring groups of devices on separate and unique System IDentities.
To further improve performance, different portions of the RF spectrum are used for separate universes. The method for accomplishing this is different for our 2.4GHz and 900MHz systems. In the 2.4GHz band we use Direct Sequence Spread Spectrum (DSSS), which divides the band into 12 channels. When an RC4Magic transmitter powers up, it scans the band and finds the quietest channel to use. In an ideal world where nothing else is using the 2.4GHz band at all, you could run 12 completely independent RC4Magic DMX universes and they will automatically distribute themselves across the available channels.
The RC4Magic-900 system uses Frequency Hopping Spread Spectrum (FHSS). In this case, the 900MHz band is divided into 64 channels, of which 25 are needed for a single universe. That selection of channels is what we call the Channel Mask, or sometimes the Frequency Mask. The selected RC4 Private System IDentity is used to generate a unique hopping sequence. Thus, even if two different universes are configured to use the same 25 radio channels, the pattern used to distribute data across those channels is different. Although there will occasionally be a data collision when more than one system arbitrarily and very briefly lands on the same RF channel at the same time, digital error detection and correction make these events unnoticeable. Even so, we generally do not run multiple systems on exactly the same Frequency Mask, we create unique sets of channels -- different Frequency Masks. There is a default Frequency Mask for each ID to make configuration simple, and we also provide a few additional ones, for a total of 8 ready-made Frequency Masks.
If you use our RC4 Commander configuration software, you can create a custom 900MHz Frequency Mask that is entirely your own. This is useful for two reasons: (1) you can specifically avoid portions of the 900MHz spectrum that are used by other systems or technologies, and (2) a custom mask adds an additional layer of data security against malicious agents. (You probably don't need to worry about evil-doers messing with your wireless, but RC4Magic is used extensively by Disney and Cirque du Soleil because of this security feature.)
For either RC4Magic or RC4Magic-900, all systems are delivered with 3 Private IDs and one Public ID. If you use all four at once, you can run four completely independent wireless DMX universes in the same space, simply by setting the IDs with the buttons on the device. You need a DMXio to transmit for each universe. Set each one to a different system ID (ID0, ID1, ID2, and ID3). Out in the show, you assign any given receiver to a specific universe by setting it to one of the four IDs. If you set a DMX4dim to ID3, it will connect to the transmitter that is operating on ID3.