Is it possible to change a remote controller's signal frequency by switching out the crystal oscillator?

        I have several old remote controllers for vehicles and I need to switch the frequency from 49MHz to 75 MHz. I think that I should be able just to switch out the crystal oscillator and replace it with a 75 MHz crystal. Does anyone have any suggestions on if this will work or not?                                                                                                                                                                                                                  Thanks!

Re-design6 years ago
You could probably go somewher in the 49 mhz range but going to 75 is out of the question. The crystal only controls the oscillator and moving that much out of freq. would stop the osc. from working at all and if it did still work the other parts of the circuit would be too far out of range to pass the signal.