You do have to be sure that you use the correct "shift" transmitter for the receiver.

JR uses one shift. Futaba uses the opposing shift. A JR TX will not operate a Futaba RX. (a Futaba TX will not operate a JR RX either.)

GWS default is the same shift as JR... but they also make Futaba compatible.

Hitech default is Futaba compatible... but they also make JR compatible.

FMA makes both and wants you to specify every time. (no default)

So there is some truth to the need to use "the same brand" of TX with the RX.