My Cobra 75wxst Cb Install (pics)

[IC Smoke]

Well I did it... I put a Cobra 75WXST CB in the truck friday night. The worst part is finding a spot for the power box BUT I found the perfect spot (as the pics display) and its working GREAT!!! low profile, easily moved from truck to truck (you can buy more than one power box) and when removed its almost un-noticable.



The only problem wit this model is going 75mph down the highway with the windows down and music on its hard to hear but with just the back window and music its fine.



I hope this helps anyone with a install



Ian

 

[IC Smoke]

I also ran the 3' whips inline with the back window seams so they woudlnt bend back in the wind and hit my stacks (soon to be installed!!! Oo. ) I drilled a hole just ahead of the 4wd shifter. You can see the hole in the 3rd pic down (above next to the black wire) BUT it wasnt to the right far enough so I had to cut part of the mounting bracket for the 4wd boot (cant tell from the outside and wont affect it too much)



Ian

 

[BHowell]

CB install

Nice looking install!

I took an even easier route with my Cobra 75. I put the power box under the driver's seat.

 

[Hammer]

Ian...

Now, for the ins and outs of so called "dual antennas". While it is a proven fact that properly installed Co-Phased antennas can exhibit quite a bit of signal gain over a single antenna, there are several things that have to be taken into consideration.



First and foremost, the antennas must be spaced exactly 1/4 wavelength apart in order to exhibit the elongated figure eight pattern you would be looking for. At CB frequencies, this would be approximately 8. 5 feet (102 inches). Anything over or less than that distance will distort the radiation pattern.



In order to feed these Co-Phased antennas, one cannot use standard 52 Ohm Co-Axial cable, as the total impedance of the two would only be approximately 25 ohms. Normally cable in the vicinity of 75 ohm is used to make the phasing harness.



I am not a believer of co-phased antennas for mobile work. I think the pain of installation, and tuning them, vs the actual signal gain for point to point low power mobile work are not worth the expenditure. Plus add to the fact the only true way to get the "dual antennas" into the 1/4 wave increment and make them work properly would be to mount on on the front of your truck and one to the rear makes them a hassle from the start. It is true alot of guys run them like this and close together,but,how many have ever looked at how the antennas tuned on a antenna anyalyzer. I realize its your truck but I figured after all your hard work installing the radio someone should tell you about the antennas so you do not have to tear the radio out because its been burned up due to poorly performing antennas... ... ..... Andy

 

[IC Smoke]

Dont worry Hammer I unhooked one today and just placed it with a bolt in order to hold it up after having poor reception, I went dual for looks knowing that one would either have to be cut or "bolted". Thanks for the info though!! and more guys should read your post!!



Thanks!



Ian

 

[JMarhofke]

I plugged in a Motorola speaker in the speaker "jack" on the box of mine, and the audio difference was like night & day. Any external speaker will make a huge improvement, I just happened to have a Motorola one lying around.



Jim

 

[ToolManTimTaylor]

someone should tell you about the antennas so you do not have to tear the radio out because its been burned up due to poorly performing antennas... ... ..... Andy

DAMN!! Where the heck were ya Andy when I Co-Phased and Capsized?

 

[jkalchik]

Very cool!



Gotta do something like that in mine one of these days. Although, rather than hanging antennas in the bed, I'm going to use the FireStik no-drill hood mount.

 

[Colonel102]

Hey Hammer

Hammer,

You brought up a good question. I'm getting ready to mount both a CB and ham radio (2m/440) antennas on the truck. Am I going to run into any problems like with the duals? Or is the freq. difference so great that I have nothing to worry about?

I plan on mounting the 2 antennas in the stake holes closest to the cab. Both around 55-60" in length. And ofcourse the width of the truck bed apart.

Any info would be great. Thanks



Colonel

 

[Hammer]

DAMN!! Where the heck were ya Andy when I Co-Phased and Capsized?

If you capsized I am certain just like if I had they would need a very large recovery vehicle to save us,LOL :-laf :-laf .



Colonel102. .

With the width of bed providing space between them you should not have any problems. I am one who doesn't run any antennas close together as I am a firm believer in close creates problems with wavelength distribution. Being that your other rig is a 2m/440 with the distance of the antennas apart you should be ok. I would consider making sure you tune with a antenna analyzer to be certain though. This way you will be able to optimize both rigs and ensure yourself they both are setup for optimal performance. The antenna analyzer will tell you if the antennas are going to be "happy" at the distance of the bed width... . Andy

 

[I-6DZL]

What size amplifier comes from the factory in this unit ?



Pro's/ Con's of installing a larger amplifier ??



Thanks

Curtis