Chevy Cobalt FT-7800 / Remote Head (Step by Step)

[OpSec]

Get a simple $5 black Antenex or Maxrad VHF 1/4w cut for 142-151 MHz. This will give you the needed bandwidth on VHF and can serve as a 3/4w on UHF. I have seen this work on some cars and not on others, so YMMV with the UHF side...but I'm willing to bet it may work on your install.

In my experience, I have never seen one of those Diamond or Comet antennas work any better than a simple land mobile-grade antenna. They are overpriced and over-hyped in my opinion.

 

[appalachianscanner]

Black Porcupine Syndrome lol

I added the other Antenna I was talking about, Whoever thought nmo mounts were not fun should have a 3/4 inch hole drilled in their head LOL

Antenex "ABFT" 24'' quarterwave From AES ordered Monday Evening, got it this morning " UPS & AES +1" This install's, cheaper, works better (for RX tested so far) and from the contruction, appears sturdier.....good advice Stateboy!

Just a plain jane quaterwaver, using as a portable scanner antenna untill i can muster up enough money for something better.... not the tradittional ultra low profile base but, this one looks a bit more sturdy, since its flexing when i open the trunk, against the back glass...

One thing neat about this atnenna is that it includes a nice lil rubber gasket (not the ring gasket) that goes against the surface your mounting to to lock out moisture....

As far as performance, Im gettin S40+ on all my local 800 MHz and airband, and VHF and I heard some people paving (using frs) about 4 miles away.... YES! havnt tested the swrs yet

<a href="http://s80.photobucket.com/albums/j181/svfs/radio/?action=view&current=2-1.jpg" target="_blank"><img src="http://i80.photobucket.com/albums/j181/svfs/radio/2-1.jpg" border="0" alt="Photobucket"></a>

<a href="http://s80.photobucket.com/albums/j181/svfs/radio/?action=view&current=2-2.jpg" target="_blank"><img src="http://i80.photobucket.com/albums/j181/svfs/radio/2-2.jpg" border="0" alt="Photobucket"></a>

<a href="http://s80.photobucket.com/albums/j181/svfs/radio/?action=view&current=2-3.jpg" target="_blank"><img src="http://i80.photobucket.com/albums/j181/svfs/radio/2-3.jpg" border="0" alt="Photobucket"></a>

 

[hippieman556]

nice looking set up you got

 

[appalachianscanner]

Re:

thanks! I trimmed off about 6 inches and got the swrs less than ~1.5 140-150 and 430-460 spikes a little at 147 then drops back down @ 150 also at 450 then back down at 452 weird!? I was gonna be a lil more of perfectionist and do more trimmin but im happy where im at.... SWRS are not as flat as the diamond ill admit, but im gettin my 800 Mhz back....this will deff be acceptable for a scanner when I get one ordered and put in with a remote mount kit.

 

[K4APR]

When you had one NMO to mount, you could have just as easily did it in the middle, where it belongs. The channeling on the underside of the trunk lid is hollow. What you have to do is drill the 3/4" hole and then fish the coax down the channel to either corners where they open up or drill a whole in the channel to route the coax out. The best thing to do is bring it out right near the hinge. That way, you can route the coax down the hinge arm and keep it neat and snag free.

Since you went with two antennas to balance it out, center line is not an issue, only you should have bisected the trunk and then bisected those halfs and mounted the antennas at these bisect lines. The antennas would have been equal along the horizontal line of the trunk and more importantly you would have better SEPERATION between them.

The typical rule of thumb is keeping the antennas at least a 1/4 wavelength apart, using the the lowest freq antenna for gauging this distance. In this case, I would say the VHF (highband, 2M, whathaveyou) is the lowest frequency. This would require a 1/4 wave's distance at the 140-160 range. Roughly 18".

Just my $0.02 but I am coming from 15 years install experience (5 professional).