Antenna for Cascadia?

You have the best antenna for the Cascadia (in my opinion).
What you can do with the Skip shooter, is to get a 2' section 1/4" piece of PVC and slide it down to the base of the antenna. That will help keep it from flexing.
The other antenna alternatives would be a 7' firestik which is less flexible than the skip shooter, or you can use a 102" whip (which is what I use). Those would be my suggestion.
Hope this helps.

 

Yes, a 1/4" piece of PVC that you would find at like home depot. Slide over your antenna, and down to the base, that will help.

Regardless of what antenna you use, you should use the 2 bolt bracket, not just a single bolt perch style. I use the Pro Comm mount, HD Wilson stud with a 102" whip.and a 5" Wilson SS extension. Run a braided ground strap from your mount to the door hinge and you should be good to go. Be aware tho, that even when the antenna is tilted forward (under 13'6") it will raise up above 14' at highway speed. The angle at which you tilt it forward will be determined by your highway speed. You want the antenna straight up (and not tilted backwards) when your up to speed on the highway.
You can avoid the over height (illegal) antenna by sticking to a 7' skipshooter or Firestik tho.

 

I cant help you with the impedance issue, hopefully someone smarter than me will chime in. With my setup now, I can talk around 10-11 miles on a barefoot, untuned Cobra.

 

I ran a six foot skip shooter on my Cascadia daycab. YMI means 3/4 inch piece of PVC pipe, Home Dept sells it in the plumbing section in 3 or 4 foot sections. I painted mine black to match the six foot antenna, no more flexing at the base, and it fits snugly around the bottom of the antenna stud.

 

No you would probably need a 1.5 inch pipe to be safe for that one. 1.25 inch might work, just have to deal with buying a 10 foot piece for $5 or $6 and throwing away the rest. To make it snug around the antenna you could put some foam down in there since it will be much wider than the skipshooter.