Cascadia Antenna Solutions

Elevating the antenna probably made it much easier to hear incoming signals maybe.
Separating the feed point from the ground plane by 40 inches drastically increases ground losses making it more difficult to transmit effectively

 

Seems the only two satisfied with their antennas on these trucks is Mike and Volvo one I think uses likes the 7ft.skipshooter another I think uses a 102" whip I can't remember who has what ...

 

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Well I'm not never have been a fan of the tilt/angle deal it's defeating a purpose.... the only reason I've got the 20degree tilt going at the moment is for height issues..... if you walk around my trk. at any angle front/back side to side there's nothing blocking that coil in any direction nor is there blockage from the trk.itself.... the 27" k hanging out there in no man's land has blockage from the truck.... bottom line I'll not foo foo it. I think predator antennas stink. Thats a nice word .There I said it !!! Build a better antenna rabbi or someone ----------- please

 

Is that a trick question??

 

Seeing these cascadias have little to noooo ground plane,how does haveing the feed point near the mount help with that...Was thinkin bout that last nite while tryin to decipher my arrl bible...

 

Im almost sure its not antenna...Its how and what the trucks been built with..Ant mount positions and so on..
I forget who said it but these trucks have so much plastic and plastic bushings and glued panels ect that there is little to nothing for the ant to see as a ground plane..So mow we are forced to simulate it somehow..Some methods are crap and some are great...
For all the newer plastic trucks we need the great cb/ant gods to create a working plan and anyone can apply the method and get decient to out standing results..
For now without dismantleing these trucks and useing a bizzillion bonding straps we get band aid solutions..

 

Did you read that section from that website I quoted where it specifically tells you not to mount your antenna on top of a pole and why?
I don't make this stuff up I just follow the rules to make it work

 

I musta missed it..Can you post it again?
Not so concerned about the pole just how mounting my ant feed near the mount itself helps where there seems to be no ground as is....
I k ew these trucks didnt have much but when i got the ohm meter out and saw it..I could almost swear my heart stopped..
Shoulda been listening and reading long before this instead of being so darn stubborn and goin by crap i hears yrs ago..

 

Read carefully..
Many amateurs harbor the notion that DC grounding an antenna mount will magically act as, or replace, a ground Plane. It will not! It may DC ground the antenna's base, and it just might RF ground it too depending on the straps length and width versus the frequency of operation. However, it is by no means a replacement for an adequate ground plane under the antenna! Incidentally, the term ground plane is a bit of a misnomer (see next section).

The body of the vehicle and the capacitive coupling to the surface under the vehicle, is acting as a ground plane, and a lossy one at that! Typical ground plane losses vary between 2 and 10 ohms, 10 through 80 meters respectively, but in the real world they may be as high as 20Ω on 80 meters. It is also possible to have higher ground losses on 40 meters, than on 80 meters. The primary cause are standing waves between the body of the vehicle, and the surface under it. This fact should not be confused with the term SWR!

Since ground losses dominate the efficiency equation, decreasing them by just one ohm, can make a significant increase in ERP (effective radiated power). And be advised, ground loss cannot be measured with a common ohmmeter or determined by measuring the input impedance of your antenna!

Further, excessive ground losses directly relate to the level of common mode currents. Common mode current causes all sorts of RFI issues, both ingress and egress, and a can drastically reduce the receiver's SNR.
(Noisy awful receive)
Put another way, excessive ground losses can turn an otherwise efficient antenna system into an also-ran.

In a mobile scenario, there is one other ground we need to concern ourselves with, and that's a proper RF ground return for the coax shield.Remember, RF must flow back to its source. It will do so in the shortest path it can find (the one with the least resistance). Ideally that's within the coax cable. However, improper mounting (atop long posts, extended brackets, magnet mounts, clamps, and luggage racks) causes an inordinate amount of RF to flow on the outside of the coax (common mode current), or down inadequately-choked motor control leads if so equipped. Incidentally, common mode current flow is the main cause for both egressed and ingressed RFI.


Notice:
However, improper mounting (atop long posts, extended brackets, magnet mounts, clamps, and luggage racks) causes an inordinate amount of RF to flow on the outside of the coax (common mode current)

 

Ohhh ok..yeah i saw that..
Wish i knew how to measure the differences....On the ss mount i have(not the one from bobs you suggested)now if i remember correctly the #'s were outta wack cause of the lack of gp..Dont ask me what the #'s were lol..Its misty out today but i might get the git up n go to pull off the tall mount and see what #'s i do get buy useing the 22" mounted at the door..Other than swr/resonance ect from an aa,what should i notice?