Why can my PRO-164 get better signals overall over my PSR-500? i can put them in the same spot my 164 can even pick up trunked signals further away than my 500...both have the rubber ducky antenna....when i try hooking my 500 up to an outside antenna it gets 100% worse it just kills the signals....is there anything i can do??? settings? and the trunked systems are moto type2...only 2 p25 systems thanks in advance