New owner of used RV - Very poor TV reception

[wpj54]

I am a New owner of a used National Class A RV. Unit has a batwing antenna, a conventional analog TV, what I believe is a power booster built in, with on/off switch. I have added a digital converter box, a "wingman" UHF add on, and today I bought a 25 db amplifier. I still get very poor reception. The RV is a 1998 model, do you suppose I need to replace coax cable from antenna on roof to whereever it goes, I suppose built in booster? Can you help me with troule shooting the problem, Also I don't really know what position the antenna should be in to point at station I am trying to recieve. Which part of the antenna do you point with? Is it the center section opposite where the coax connects? As you have probably realized I need lots of help. My zip code is 71203, located at 1201 Finks Hideaway Road, if you want to get a look at the stations avaiable in our area to help me understand the antenna operation. Oh yeah, what I am calling the built in power booster has a coax in and out and two other wires attached, Itook it loose from the cabinet to see what was behind it.