ORIGINAL: Solid Hit
Have you checked the rx? It could have been a bad or loose crystal. Does the Optic 6 have the spectrum module? The module can be a problem but an easy fix without having to send it back to Hitech.
Thanks for your ideas...
The Hitec Crystal was indeed plugged into the Hitec Rx tightly. I don't know what else I could check for on the Rx.
Yes, the Optic has the Spectrum module, which I had taped per Hitec's recommendation. I sent back both the Tx and Spectrum to HiTec for evaluation (and to put the "corrected" replacement back case on the Tx). I didn't send the Rx back because it's installed and I was too lazy to uninstall it.
One thing I could have done right after the failure was to change the Spectrum's frequency and test the Tx on my other plane. I may have to do that if Hitec finds nothing wrong (ugh).