John,

I have asked this same question before and the answer I got was that it is ok to change a crystal on an RX as long as you stay in the same "low" or "high" band of the RX.

i.e. You would not want to put a ch 50 crystal in a low band RX that originally had a ch 11 crystal. But putting a ch 26 in that same low band RX would work fine. In fact, I believe the low band RX is actually "tuned" for ch 18.

Ann Marie would have more specifics. Also, check the futaba-rc.com faq page. They may cover this exact question.

FYI- I believe AM is on vacation for a while.

Mike