Cascadia Antenna Solutions

I'm sure you're right it doesn't apply to the dipole but that isn't my first Avenue of choice for that particular truck. Shunt matching the two driven elements mounted outside the rear fairings would be my first choice for that truck and if that didn't work to my liking only then would I resort to stacking dipoles off the same brackets.

 

I'm returning to this thread for a couple things.

I ran into someone this morning who specialists in mobile antennas. we got to talking about my experiments on cascadias and other trucks and told him about the dipole solution some of you tried to make work.

He made a few suggestions and explained why sometimes they won't work. One reason is that you are building a co-linear system without spacing the elements properly. there is a formula he gave for the gap between the elements that have to take place - space = .65(λ/2)

You do the math. I don't have the time to think it through this morning.

He also suggested that a Balun be put in place at the feed point of the antenna because the impedance of the antenna won't be close to 50 ohms but closer to 450 ohms. So even though you all are using those fancy antenna analyzers, they don't model the antenna and can be fooled into giving wrong reasons.

 

so what's a balun I have no idea and can admit just that ???

 

It is a little circuit that takes the unbalanced line like a coax and makes it a balanced line so the signal flows better - I know it isn't a great explanation but I am tired from the trip and can't think of a better way to put it.

In a dipole antenna, there is two segments of the antenna that the signal flows. If you take a ladder line or a parallel line from the radio output to the antenna, it is considered balanced because both segments of the line are equal. If you use coax, you have to split that up for the signal to go in one direction - otherwise you get a current imbalance which is called common mode - and it reduces the power going to the main segment of the antenna, reflecting back some or using the coax shielding as part of the antenna - bad thing.

 

That's the only way you can do it. The mount is too close to the body otherwise. That 45 degree angle is necessary to avoid Reflection from the body.

 

45 deg of angle aint helpin with range according to a calculator i found for that..Wish i had a link to it on my phone..
My.wild.guess if all else was perfect the max would be 15-20 miles..Yeah i know,i would kill for that range..Again im guessing to based on about a 20 deg angle im useing..

 

Ignore the calculator. Try it and see what happens..

 

well you say your predator didn't do well on your field strength meter that's because they dont. I've never heard of a predator being compared to a 102" I'm just not seeing that or believing that. just saying

 

Cb radio magizine was one of the places i remember seeing it..
Not the antenna cause im haven even more issues teyin to tune a 5 ft on same mount and useing a lower mount i cant get anythin good with my.7footer....
Its either the stud(90% sure its not that)or the ss mount..

 

if you get to tjs shop again they sell a better top stud than what your using sells for $25 a better bottom stud helps with stability of the whole unit. rabbi told me about that made sense so i found and bought one... bobs cb sells the top flat plate on the 40" pole mount in stainless sells which is much better/stronger than the aluminum one it comes with........