Questions - Short Load Antenna & Ground Plane

[REBinc]

I currently have a Uniden 510xl with a Little Wil. I purchased them from Sparky's CB here in IL and I'm very happy with their performance (4-5 miles usually). I don't usually leave the CB on the car, I just put it on the trunk for road trips

My current setup:
http://i47.photobucket.com/albums/f181/rebinc/GTO/2009/07-11/Dragon9.jpg

I'm considering a new mount to permanently fix the CB to my car. I don't have a huge truck or anything, so a huge antenna would look ridiculous.Plus, with all the other consideration I give to my car, I don't want it to look like an eyesore. My plan is to conceal the new antenna as if it were a stock antenna, and mount it in the front of the car in the gap between the hood and the windshield.I'll still be using the Uniden 510xl.

This is where my two questions come from:
-My antenna will be securely attached to metal (top of firewall), but it's not a nice continuous flat surface like the trunk. When the term ground plane is use, is it only crucial to be grounded, or have it on a plane? I couldn't find any great descriptions of it, it will be close to my hood, but not attached to it. I'm going to mount it on under the passenger side wiper:

-What is the performance of the Wilson Short Load? Is is comparable to my Little Wil, better, worse? My current plan is to buy a Wilson 1000 base and their short load, is there a better combination for my needs? I'd like to stay away from fiberglass antennas and keep with the thinner whips.

Goals:
Same range or better (3 mile minimum)
Make sure I can get a good SWR

 

[REBinc]

Since no one has any suggestions, does anyone know a good website where I can learn more about the physics of a CB antenna?

 

[DX949]

Since no one has any suggestions, does anyone know a good website where I can learn more about the physics of a CB antenna?

check this site out.... Choose & Install a CB Antenna, Mount, & Cable

You can always try it. nice car.

 

[Mike-KC8OWL]

Most mobile antennas (especially CB) are 1/4 wave antennas electrically by virtue of the radial and loading coil that is used to 'shorten' the antenna physically but still make it appear to the radio as a full 1/4 wave.

1/4 wave antennas need a ground plane or surface also (ideally) of 1/4 wave to bring the impedance to 50 ohms (to match the output of the transmitter) and also to provide the most efficient radiation pattern (for a 1/4 wave, visualize the radiation pattern as a doughnut shape with the antenna in the center).

The best place to mount any mobile antenna is in the center of the roof but this is not always ideal. If you mount your antenna where you described, I suspect it will work well, but not as well as if it were in the ideal position of the center of the roof. You will have a good ground plane off of the hood of the vehicle, but your radiation pattern will probably be maximized in the direction where a a good ground plane is available. Since your goal is not maximum distance, I suspect this will work fine. (The doughnut I mentioned earlier may now be disfigured and no longer round).

My only concern would be the proximity of the antenna to things like high energy ignition, etc that may generate additional noise in the radio, but this is something that you will only know if you try it.

I hope this helped -

Mike

 

[REBinc]

Thanks, that does help a lot. I mostly talk to cars in front of me as it is, so I'm glad to hear that would be my strongest direction. I didn't have barely anything to the front of my antenna when it was on the trunk, so it may even be better than what I have now.

I think I'll go ahead and order everything necessary, and talk it over with the ship as I order.

 

[Mike-KC8OWL]

Post a picture of the install when you are all finished. Several years ago I had a 510xl that I was able to mount inside of my center console on my S-10 Blazer which kept the radio completely out of sight when it was not in use. At that time I was using a K40 antenna and was also very happy with how well that little radio performed.

Thanks ... Mike

 

[REBinc]

Yeah, that's why I bought the 510xl. It's so small.

and an auxiliary speaker on my B-pillar

 

[Mike-KC8OWL]

Sweet install - great job!

I still have my 510xl that I will use every once in a while when we go on vacation and drive long distances. In those cases it is a lot more useful to hear about what is going on a couple miles ahead using the CB rather than my amateur or GMRS equipment. This summer we drove from Ohio to S. Carolina and it saved me from a few traffic issues that otherwise I would have never known about. When I use it, I use a K30 antenna with it.

Thanks ...

 

[SCPD]

Did you mount the antenna on the front and if yoou do does the engine motor noise bother your radio. If it doesnt your home free. However as a "radio installer" amongst other things I would suggest the back to get the antenna away from a potential bad noise source- The engines alternator,ignition system and other stuff.can be a disaster for even FM transceivers if they mess up....Good Lock and you inside install looks great..Wanta Job in SC when we start hiring after this downsizing and budget cuts

 

[REBinc]

I finally got the piece off today without breaking it, and the piece I thought was metal is actually plastic, and the metal beneath that is about 3-4" below the hood, plus it's not level and very uneven. I would have to fab something up to bring it up to the level I need. I think my best bet may be a lip mount on the back edge of the hood.

 

[Dirge]

My current setup:
http://i47.photobucket.com/albums/f181/rebinc/GTO/2009/07-11/Dragon9.jpg

I'm considering a new mount to permanently fix the CB to my car. I don't have a huge truck or anything, so a huge antenna would look ridiculous.Plus, with all the other consideration I give to my car, I don't want it to look like an eyesore.

Looks okay to me. But I was 5 when “Smokey and the Bandit” came out. So to me, a muscle car without a whip antenna doesn't look right.:twisted: To each his own.

 

[ERICMYERS]

NICE install guy.
Me, I like the skinny, relatively tall whip of the 'lil wil' most of the time on mine. I mount on the center of teh trunk lid for a good groundplane. It's a bit of a clanger in the garage, but still pretty low profile vs a fiberglass stick which is thicker. Shorties work OK - cheap enough to try...the lil wil is great for the money.

 

[hockeyshrink]

Looks okay to me. But I was 5 when “Smokey and the Bandit” came out. So to me, a muscle car without a whip antenna doesn't look right.:twisted: To each his own.

...Me, I like the skinny, relatively tall whip of the 'lil wil' most of the time on mine. I mount on the center of teh trunk lid for a good groundplane. It's a bit of a clanger in the garage, but still pretty low profile vs a fiberglass stick which is thicker.

If you are not familiar with it, check out The Gumball Rally, (circa late 70's) about an illegal race from NYC to the parking lot of the Queen Mary. They have everything from a Ferrari, Cobra, and Camaro to a van filled with gas, Mercedes, and even a motorcycle racing. Most of them are running a HyGain cb with what looks like a 3' white fiberglass whip on the bumpber.

Just some perspective compared to the roof mount base loaded gain antenna on BAN-ONE.

These days, replace the cb with GMRS and run a chrome 1/4 wave whip (6") to look like NASCAR!

 

[SCPD]

Sweet setup!! I love the concealed look.