I ran into MICRO1700 at a laundromat and we got to talking.
MICRO had an idea I've never thought of for Part 15 FM stations used as Studio-Transmitter-Links (STL), but otherwise do not want to attract too much attention in their signal range.
The secret: use in-between channels!
I tried it. It works. I moved from 89.5 to 89.6 and am now "off the dial" for anyone flipping to ordinary digital channels, but my digital radios are capable of tuning the in-betweens and of course analog receivers can do it.
The one thing that needs checking is that I want to move AWAY from any nearby stations and not TOWARD them.
Part 15 is fun all over again.