No Debian Dog, I never thought about the ferrite ring. I kind of assumed it was the location of the receiver antenna or the 5 foot height being right inline with the tip of my TX antenna. Thats why I went with the ducky. If it were stray interference, I thought it would be at any altitude. Figures too, I just made an order from Helidirect this AM. I may have to e-mail them and see if they can add one to my order. I guess it cant hurt to try it..
Thanks