I mounted a R.S. 20-176 antenna (which gets rave reviews) just above the roofline and attached the mounting bracket to the back of my “butterfly” uhf TV antenna with the scanner antenna radials only a couple of inches above the T.V antenna.. The scanner antenna now receives worse outside than it did just sitting on a dresser indoors (I used a good quality RG8 cable). Could the TV antenna be interfering with the scanner antenna? Do I need to separate them with an insulated (plastic conduit perhaps) mast? THANKS!