Airsoft Com systems. How do they work?

I am not familiar with what you use, but most serious airsofters in our area use a form of 2-way radios, such as a Motorola Talkabout model. I use one that has FRS and GMRS channels, channel locking codes, and a 12 mile radius. For a pair, you can expect to drop about $40, which is literally nothing and worth it to keep in contact with your teammates.

However, not everyone has to use the same radio. Consider it similar to a radio broadcast music station you might listen in your car. The broadcast point is singular, yet it relays its information to thousands of homes and vehicles that use different brands and technology. Similar to how you identify a radio station with numbers, each FRS and GMRS channel also has a number. FRS is usually 1-14 which cheaper radios have. GMRS is anything above channel 14. A more expensive radio will also come with channel locking codes, which allows you to set a secondary number to a channel (lets say channel 1-24) so that people only tuning to 1-0 will not be able to hear you, even though you are on the same channel. However, if your teammates have cheaper radios, you will have to use the channel without a code, otherwise they cannot hear you. A general communication to channel 1 would say 1-0 on your screen.

Usually on airsoft games it is against the rules to listen in on enemy radio chatter, but if you have the advantage of using a channel locking feature, definitely do it. If you are running with a team on a big operation, they will let you know the channels you are supposed to be on, but be aware, that radio chatter on the main command channel is usually restricted to ranking officers (such as squad leaders) only so that command can ask for situation reports and not get a whole bunch of chatter from 2 guys trying to move up. If you are just running your squad independently of the main group (say in a run n gun game, where the game type is similar to a Team Deathmatch) I would suggest assigning your own channel frequency for your members to communicate on.

I would also support getting a radio/walkie talkie with a phone headset jack. This allows you to get an earpiece with a boom microphone that attaches to your ear so you can hear communications clearly and respond with minimal outside noise that may alert foes to your presence. You can pick up motorola brand headsets for around 12 dollars.

If you have any questions regarding my answer, feel free to message me!

Generally each team will use it's own frequency. It means that more or less any com system can communicate with any other com system. However, if people are playing with friends, they'll often use their own frequency, so there's less traffic and they only hear what their friends have to say. Remember that the enemy can very easily listen in to your conversations, so try to avoid using coms unless essential.

Hope this helps