How important is it to not be near anything when tuning.

Hmmmmm, tried one with various length shafts and finally got a good reading with a 4ft shaft, but ended up just using a 7ft Skip Shooter. I didn't want to spend the $$ for a piece of stainless steel to make a 4' shaft.

 

I use a single 2k with a 10" shaft on mine (07 Columbia) and LMR240 coax. You have to remove a good 4" of the whip at least to get it in tune.

I don't have a tape measure with me or I'd measure it and tell you about how long it needs to be.

 

You can put two together. And yes, the load coil further away from the truck body the better. You do have to re-tune (cut the whip) some if you add shaft length. A couple of inches or so will do it so don't get carried away.

 

My experience is when the antenna is put near another antenna, it impacts my Swr's, usually several tenths of a point. If you mount an antenna near a factory antenna, your swr's might be 1.7. Take the factory antenna off and they may drop to 1.3. Same rules apply to large objects within five or ten feet of the radiating pattern.

 

Not as long as there is a good electrical connection in regard to the shaft. As far as whip length goes, just trim a 1/2" or so the first time and check it. As it drops closer to 1.5:1, cut less and less off at a time. If I didn't see something positive happen after cutting off couple of inches, I'd stop. The longer the whip the better the antenna works.

 

I usually quit cutting at an SWR of about 1.5 or so. At that point, the theoretical signal loss is only about 4% as I recall. Folks with antenna analyzers find that the lowest SWR as seen on simple SWR meters isn't necessarily the best point for antenna resonance / effectiveness, because the SWR reading by itself can be misleading.

 

I'm happy at 1.5:1 also, but I will usually trim just a little more and see where it goes......could start back up again!