There are a couple of things that you are going to have to just live with because you're driving a truck that isn't exactly easy to put an antenna on and have it operate most effectively. That doesn't mean your 'Columbia freight liner' specifically, but any semi-tractor and trailer. Antennas would rather be 'above' any metal rather than 'beside' any metal (carry that just a little bit further and say they don't care for being 'under' any metal either). It's also a fact that 'full sized' antennas tend to radiate a 'better' pattern than shortened antennas will produce. And since at 11 meters a 'full sized' antenna is something like 9 feet long/tall, it's just not very practical to put a 9 foot tall antenna on top of a semi-tractor. Right? So don't expect 'perfection', every installation is going to be a compromise in some way.
Having said all that, you can certainly optimize your set up. That typically means doing a good job of tuning your antenna, and feeding it a signal that's reasonably strong. That 'reasonably strong' thingy is another place where -practical- is more important than just 'more'. That antenna tuning thing is much more important than the power thing.
Antenna tuning isn't exactly easy, depending on how you do it, and requires more than just an SWR meter (just like tuning an engine requires more than just a timing light). Not exactly what you normally hear, but it's true anyway.
That all means that an antenna that's 'close' to that 9 foot thingy, mounted as high, or above more metal than beside it, and then really giving it a good tune up, while keeping things as 'practical' as possible, would be your best bet. The only real 'trick' in any of that is that 'practical' part, which certainly won't be the same in every case. The other 'catch' is that 'Momma Nature' always has the last word as far as 'range' goes because 'She's the one who controls propagation, which is always the deciding factor. If you EVER figure out how to keep 'Momma nature' happy even 50% of the time, would you PLEASE tell me how to do it too?? (Don't tell anyone else, just me! We'll make a fortune!)
One thought is what kind of antenna does that guy at work use who does so well? Any chance of you getting one like it?
And lastly, be careful about 'opinions', stick to facts where possible. Every antenna maker in the world says their antenna is 'best'. That's an opinion. And unfortunately, it doesn't stand up under examination in most cases. See where that's going?
I won't make any specific suggestions about what antenna to get. The one you spoke of is certainly one option. (That power rating means nothing unless you plan on using that much power, BTW. And it is always dependent on how well the @#$ thing is tuned.)
Good luck.
- 'Doc
