Ken, sorry I read more into what you said than was there. I'm trying to educate myself as to what we could actually interfere with, moslty in reference to safety, and leaving the legal issues aside for now. As an example of what I didn't know but do now, I was not aware that our frequencys were in the same range as TV signals. I knew we had industrial applications in our range. Of course, in my somewhat oversimplified veiw, TV would qualify as industrial.
Jburry, I certainly would not want to interfere with such equipment. The crane I used could lift 4800 lbs and reach out around 40 or 50 feet horizontally with that load. Would have been very easy to have had interference cause me to drop a skid of shingles through someones roof, and I would never have known why. However, I had thought that the transmit power used by such devices was such that it would be next to impossible for an rc system to cause interference. I was just trying to find out if that was true.
Now, don't flame me here. I am not trying to promote, condone, or justify changing Tx crystals. I have never done this to an airborne Tx, nor do I intend to. I have, however, done this in 75mhz ground systems for years. It was common practice and even expected at large races to avoid conflicts. I only own one ground system that I got with the original Xtal set and though I still have the set I doubt it is in that Tx. Actually just remembered that I now own some 27mhz systems and those are original.
I guess what I am wondering is what am I actually going to interfere with with an altered 75 band system? Legal implications aside that is.