I have several MU22 series radios. they work
The MU22 will not do what you are attempting to do. You can't put in a control voltage on one end and have it come out on the other. 2-way radios Tx and Rx (communicate) using audio signals. The speaker output and audio input are audio signals, not DC voltages or control voltages.
A radio can be used as a remote control method, however, a conversion needs to be done on both ends. Example: Turning a lamp on, at the Tx end you would have a converter which will take a control signal and convert it to an audio tone. On the Rx end (the lamp) there will be another converter, this converter listens for the correct tone and when it gets the correct tone, it turns on the lamp. This example is what you call tone-remote control, which is one of the most common methods for using 2-way radios for remote control applications.
There are other methods for remote control such as telemetry. Keywords to google would be telemetry and tone remote control.
Best regards. Read More At : MU21CV (1 Channel) 2-Way Radio...