joegib,

First of all, the Hitec crystal will work fine. I have the exact setup you mention (r127df and hitec crystal on ch. 19) and it works perfectly.

Second, Futaba does split it receivers into low band and high band. Low band is channel 11 thru 35 and high band is 36 thru 60. You may have trouble putting a ch. 53 crystal in a low band receiver. FYI, ch. 18 and ch. 53 are the "tuning centers" for their respective bands even though they are not numerically the center.

Hope this helps and good luck.