Your antenna should be 2/3s above the cab as mentioned before. Thats probably the biggest problem your having. Also ground wires must be kept short as possible. Try a longer antenna. I would recommend a fire stik 2. I have had good luck tuning them to all sorts of things that should have never worked. Once tunned one to an upside down filling cabinet drawer on my friends roof.
We managed to get a 1:3 SWR on it.
He was not able to have a big base antenna so it worked pretty good.
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-Justin
1984 F250 6.9 C6 2WD Push Button Wellman GPs, No Soup bowl. Wix 33439 Water Separator, Carter P4594 fuel pump, Custom 3" Exhaust, NTZ Oil Bypass Filter, VDO Vision water temp gauge, ISSPRO EV Pyro
http://photobucket.com/CDX825
