Servos are not radio specific. They pretty much work with any receiver on the market today. There are a few gyro specific servos that will only work with a gyro that is outputting an odd neutral pulse width and perhaps frame rate.
Receivers and transmitters are a bit different. If you're asking about 2.4 GHz systems, Futaba only talks to Futaba. Hitec only to Hitec. Airtronics only to Airtronics. JR and Spektrum kind of come out of the same hole in the ground, so JR and Spektrum play well together.
The 72/35 MHz world gets a bit murkier. IF it's a PCM system, only Brand A transmitters talk to Brand A receivers. If FM, then all bets are off, and in the US you need to begin worrying about negative/positive shift, automatic shift detection...
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