They are easy to change all you do is pull them out and push the new ones in, BUT there's more to it then just the frequency, you have to make sure that it is the same mhz as what your transmitter and receiver is, like if it's a 27mhz you have to get the crystals that are 27mhz, and you have to make sure that the transmitter and receiver have the same mhz and frequency at one time. they can have different frequency just have to have the same mhz.