Wilson Roof to Trucker 5000 ?

[Switch Kit]

With antenna loads being concedered better when they are higher (if at all possiable ?) Could or would a Wilson Trucker 5000 with a 10 inch shaft be more so closer to a center loaded then the Wilson 5000 roof mount that is flat on the surface ?

Or would there be that much differance if any ?

The Ultimate Guide to 11 Meter CB Antennas

 

[Moleculo]

Could or would a Wilson Trucker 5000 with a 10 inch shaft be more so closer to a center loaded then the Wilson 5000 roof mount that is flat on the surface ?

Yes, that's exactly what it is when you move the coil up to the middle of the antenna...a center loaded antenna. In a base loaded antenna, the max current is at the base and it tapers off to the tip. Imagine what a right triangle looks like and that is a good model of of how the current looks.

When you move the coil up toward the center of the antenna, the current stays constant and maximum all the way from the base through the coil and then tapers off after the coil. Imagine a rectangle with a right triangle on top of it. The higher the coil, the better in most cases. However, using a continuously loaded antenna is probably the worst antenna of them all.

 

[BOOTY MONSTER]

good question switch . read a lot of stuff in forums about coil height and some stuff makes sense and other stuff doesnt . from what i can tell......if youre mounting on a big truck mirror mount the 5k/2k's do a good job if the coil is above the roof . in the middle of a roof getting the coil up around 1 and 1/2 feet from the surface is about optimal . ive got a 6 inch 10k and i like it i , but would like to try a 17 inch shaft on it . apparently the height of the coil affects the angle of reflection from the roof . the roof mount wilson is a very good antenna . id rather have something that used a stud mount so its easy to try/swap different antennas and youre favorite coax if you have one . i wouldnt expect night and day differences and im sure you dont either . didnt you get a copule of 10ks a while back with different shaft lengths ? have you tried playing with them to see the different coil height effects ?

on the topic of coils on antennas .... on the mid loaded external coil antennas , do they add some horozontal charistics to the tx and rx ?

p.s. got an extra 17 inch shaft for a 10k ?

 

[BOOTY MONSTER]

hey moleculo so is the foot and a half thing wrong ? ive read top loaded is better but not really pratical for a mobile except on a fiberglass whiip . skipshooter makes a 7 ft top loaded FG antenna and it gets good comments , but ive never herd anyone suggest it beats a 10k style antenna . anyone know how they compare on a roof ?

 

[Moleculo]

on the topic of coils on antennas .... on the mid loaded external coil antennas , do they add some horozontal charistics to the tx and rx ?

No.

hey moleculo so is the foot and a half thing wrong ? ive read top loaded is better but not really pratical for a mobile except on a fiberglass whiip . skipshooter makes a 7 ft top loaded FG antenna and it gets good comments , but ive never herd anyone suggest it beats a 10k style antenna . anyone know how they compare on a roof ?

Whenever you put a loading coil near or below sheetmetal or roofs of a vehicle, you're going to get some interaction with that metal. Remember, the maximium current in a coil loaded antenna is between the base and the top of the coil. If that maximum current is being shielded or interfered with by surrounding metal, then you're going to have problems.

Mirror mounting on trucks is obviously a compromise mounting situation (so is everything except right center in the roof). If you can get the loading coil above the sheet metal roof, you're better off. If that is impractical and makes the antenna too long, then you have to do something different.

Most of the fiberglass antennas that claim to be top loaded are more realistically like a helical antenna that has some top loading characteristics. Just remember that the less coil you have in the antenna, the better.

 

[W5LZ]

A loading coil adds no 'horizontal' component to a vertical's polarization. In fact, it doesn't add that much radiating ability at all, just inductive reactance.

As far as the location of that loading coil, while higher is better so some extent, that height just isn't going to make huge differences in what you are able to hear, or your signal. Some, sure, but don't expect 'daylight/dark' differences. Or if you do see that much difference, it isn't only because of the loading coil's height on the antenna, there's just gott'a be more difference than that one. And believe it or not, having some length of 'whip/stinger' above that top coil is very nice.
- 'Doc

Oh, and just to add a little to that loading coil thingy, a helically wound whip is probably the least efficient of any antennas, except for a rubber duck. Wait, a rubber duck IS a helically wound antenna!

 

[BOOTY MONSTER]

thanks guys . i hope jim forgive me for sorta hijacking his thread .

 

[Cajun Invader]

i hope jim forgive me for sorta hijacking his thread .

 

[Switch Kit]

But as I might have suspected , it more then likely wouldn't be worth the trouble to change mounts from a Wilson 1000/5000 roof mount to another mount that would
accommodate a mount that would be suitable for the 5000 trucker only to
elevate
the antenna 10 inches off the roof.

Although science kind of says it's better , That would be alot of work to find out and one hell of a mount to handle a 10 inched shaft coming off the 5000 and the center of a cars roof. As noted , IM guessing one might need to cut 10 inches off the stinger to even things out for SWR ?

And as Doc noted , there more then likely wouldn't be that much differance in this type of situation. As far as the 10Ks go BM ,I have yet to do anything concerning them. It was just one of those things ......they were cheap. Thanks for the replies here.

 

[hotrod]

if ya buy a wilson trucker5k i believe they come with a 49inch whip
i often wondered the differences

 

[Switch Kit]

if ya buy a wilson trucker5k i believe they come with a 49inch whip
i often wondered the differences

The regular loaded 1000/5000 stingers are 62 inches , so there would be a closenesss to the differances with the 10 inch shaft added , give or take a few inches.

 

[BOOTY MONSTER]

wilsons guide to approximate stinger lengths for their various models

Wilson Antenna Tech support - Antenna Cutting Guide

 

[DJ HIP NOTIQ]

the whips on the 5000 are 49 or 49.5 inches