[quote author=Jack Christensen link=topic=230258.msg1661634#msg1661634 date=1396407512]
You bet. Good luck again, hope your XBees are OK. I'd start by reloading firmware then checking them out. Great little devices.[/quote]
I'll try once more. I thought I did, but thinking back, I may have only reloaded one of them completely. I did definitely reset the settings back to factory default on both, and I did test each one against one of the new ones, too. And NEITHER of them would be seen by the new units in any way. AFAIK, if you reset everything to factory, set a PAN ID the same on both, and set the opposite Destination addresses (and one is Coordinator AT and the other Router AT), they should always be able to "discover" the other via the RF link between them using XCTU (that "mesh" icon button under the X on the locally discovered device).
And I know before I got the new ones and was trying to get the two to talk with no Arduino, I did swap them on the breadboards, which means BOTH have been exposed to the same unprotected LED output. I did that trying to figure out if it was just that I had Coordinator and Router reversed and needed to swap those (so I didn't have to reflash each one, all I had to do was switch the output/input designations for that pin). So if that was enough to fry something, it definitely could have done it to BOTH of them.
Outside of the time wasted, well, it's a $45ish mistake. I've made much worse. 
So should a smaller but bright white LED be fine as long as I put a 1K resistor on it? Or dig out an old red LED and stay with the 1K? And to drive a pretty tiny relay would I also still want to use a transistor? Guessing so.
--Donnie