I did not know at the time that Hitec was different, thank you for answering that ken. But I do know that Futaba has a low-and-high-band situation as I own two Futaba TXs that share same frequencies with different planes (gotta make sure one is off while flying the other, was cheaper to get flight-packs for the TXs I already have so had to get same frequencies) but back to the issue here.

I only purchase high frequencies from Futaba, but assuming hsink has a Futaba RX, low and high frequencies can not be switched. I don't know about Futabas and other RXs but this is the fact with Futaba radio systems, and as bruce says even if they appear to work they will not in the long run and will cause a crash eventually.