Uniden pc 78 elite cb
This is a link to your old post re SWR 3....http://www.fixya.com/support/t180697-pc78_elite_cb
As stated SWR 3 is too high, it should be 1.5 or lower. Fiberglass antenna are kinda notorious in setup and experience wise have not performed well or at all. Maybe you should try a different antenna (metal rod). Some good brands/models I have tried with very good results are K40, Hokushin, Comet, Oscar, Maldol, Daiwa.
To check if you can receive, stick an ordinay length of wire ('bout 9' long) at the center of your radio's connector. RX should work (pls don't key the mic or TX).