Since I took the time to write this up on our team forum, I thought it might be useful for everyone here to understand how the radios work.
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So a quick rundown of how to use these. First off, go into your options>sound settings and assign buttons for next/previous channel. I used the up and down arrows on my keyboard.
Your radio transmits and receives on the various channels. You can listen to multiple channels at once, but only transmit on one at a time. Below are the main commands that we'll need to use. The syntax for all of these commands are: @command <channelname>
Note: None of this is case sensitive, and all channel names are converted to UPPER CASE.
Add - Used for adding a channel. You can have up to 32 of them, including the standard ones. Don't think of this as creating a channel, but that you're tuning the radio to a certain frequency. Its really just a keyword and anyone who has a channel with the same characters will be sharing a channel. When adding a channel, you're automatically be scanning, transmitting, and have that channel immediately selected. Usage: @add 49Team
Remove - Opposite usage to Add. Completely removes the channel from your radio only. Remember, its like a frequency. Anyone else with that channel name still has that channel to use. Usage: @remove 49Team
List - Displays a listing of all the channels in your radio, and whether you are scanning, transmitting, or have that one selected. You'll see something like:
s @Admin
st @RaceControl
st @Public
s @Drivers
st a @49Team
This means you have @Admin, @RaceControl, @Public, @Drivers, and @49Team channels in your radio. "s" before a channel means you are scanning it. You will hear/see anything sent on those channels. "t" before a channel means you can transmit to it. If you select that channel, you have "speaking permissions". I believe @Admin only has speaking permission for Admins, but that we can talk on the RaceControl channel. Not totally sure, so that list could be inaccurate. The "a" before @49Team indicates that it is the selected channel, so your voice or text messages will be shared on that one. Usage: @list
Scan - Toggles the radio to scan or not scan a particular channel. Scanning = you'll hear/see messages. You cannot unscan certain channels, such as @Admin and @RaceControl. Usage: @scan stclass
Transmit - Toggles the radio to be able to transmit or not when you select that channel. I think that, when transmit is off for a channel, it does not appear as you cycle through them with your assigned buttons. Transmit = if you can send message. Usage: @transmit @drivers
Noscan - Turns scanning off on all channels that it is possible to do so. Will basically leave you listening to Admins and Marshals. Usage: @noscan
Help - By itself @help displays a list of the available commands. @help followed by one of those commands, such as "@help transmit" will give a brief message about transmit command.
Our use
Whenever you join a league related session, in the text chat, type "@add 49Team" (without the quotes) to add the channel to your radio. Then type @list to verify it was added, and to check the scanning and transmitting status of the other channels. When in the car, I believe the most public channel we have access to is @Drivers. I think @Public also exists, but is used when outside of the car and for spectators. Under normal race conditions, it makes sense that we keep @Drivers selected. This way we can immediately communicate with a driver should the need present itself, without having to press more buttons to get to that channel. Switch to the @49Team channel (do not get this confused with @Team, again, that is only for communicating with those registered as your spotter) for when you need to talk to just the teammates. Such as pit strategies etc.
I think that covers everything...check the release notes for full details.
SR went up, iRating went down. 
"No, officer, I'm not sandbagging, I promise. Yes, officer, my disconnect was legitimate; the enter race button disappeared!"
