TFAR Tracking
If TFAR is loaded and used by the players, Zeus can enable "Toggle Radio Tracking" by placing the module down and selecting enable or disable. When enabled whenever a player uses their short range or long-range radio, it will broadcast a spectrum signal on the frequency their radio use, with the range of that particular radio. By default the option to hide friendly radio signals are enabled. But that can be enabled in CBA settings on a per player basis, or per-server/mission basis.
Only tested with TFAR 1.0.0+ (aka. TFAR Beta). I would recommend using that version anyway as that is the current supported version and have been out for years. Also the version Dedman recommends.
Listening in
If the player using the Spectrum device also have the ICOM item in their backpack, then it will work as a second TFAR radio controlled by the spectrum antenna. So if they are tracking another players TFAR signal with enough signal-strength, then they can hold own left-mouse button and listen to the enemy transmission.