RE: ParkZone Crystal
You can easily swap out the crystal. If your TX is somewhere between CH1 through CH6, it means it is a 27MHz system. You can get crystals from your local hobby shop or online like tower hobbies.
Replace the RX crystal. You may find the crystals you purchase have larger diamater legs than the ones on your RX. If the ones on your RX are in a plastic soketc - then no big deap. If not, you will need to use a small drill bit
to enlarge the holes in the PCB. Don't worry, if you ever want to go back to the original crystal, you can, just need to use a little more solder.
JC