im screwed

[crazymikey555]

OK i got my truck very well grounded th bed the chassy and the cab but i did not ground my topper would that make it go down quit a bit if i did that. but i don't think it's a ground plane problem.with 4 ft dual fire sticks i got about a 2.9 on 1 and a 2.5 and about another 2.9 on 40 and no matter what i tried it don't go down i have a springs and quick disconnects and i took the disconnects off didn't do much would it be same to run it the high.

[Phaze91460]

Lose the springs, those are large and can make quite a difference on SWR.

I dont like fiberglass antennas at all because most cant be set for SWR. Alos most wont get anywhere near the reception you can get from a steel antenna. I use the Preditor 10 K and it has incredible TX and RX. I have quite a few antennas including some matched K40 and Firestix fiberglass units. Never did get any performance out of them. Just look good thats all.

Are you using a cophaze wire or a splitter ?
What is your camper top made out of ? Fiberglass, aluminum, etc.

[crazymikey555]

aluminum um ith's co phased. they have tunable tips so it's easy to adjust the swr

[BigBopper]

If you want to run 2 antennas, buy Francis pre-tuned antennas

[crazymikey555]

i took out the springs now it's at about 2.5 on 40 and 1 thank you for the help.

[Phaze91460]

If your bed is grounded, how is your top attached to the bed. Wouldnt take much to make a good ground between the two.

If you go to the newby section you will find a section on SWR which will give you direction but the short version .........

I believe on a cophaze setup you can disconnect one antenna and tune the other. Is chan 1 any lower or higher that 40

Note: On my Pred 10K I had to use a post it to tell that there was a difference in measurement

[crazymikey555]

oo i used that i ran ground wires from chasy to bed cab to bed and chasy to cab but not the topper. but i got it 2.5 on one and 2.5 on 40 now

[Rex_foxhound]

How far apart are the antennas?

[231]

How far apart are the antennas?

Ditto. Cophased set ups will never work properly unless spaced right. They need to be at least 8' (closer to 1/4 wave length) or more to work. IMO you are better off running a single antenna toward the center of the rig on top.

As far as tuning them goes, I've always tuned them individually...meaning you use the standard 50ohm coax to each antenna, tune it, then hook up the 75ohm harness assembly and check again. If the SWR's are high, likely one or both of these things are the problem;
1.) spaced incorrectly causing reflection (or fighting each other's signal)
2.) 75ohm harness has a problem.

Hope that helps some.

[jessejamesdallas]

How far apart are the antennas?

Ditto. Cophased set ups will never work properly unless spaced right. They need to be at least 8' (closer to 1/4 wave length) or more to work. IMO you are better off running a single antenna toward the center of the rig on top.

As far as tuning them goes, I've always tuned them individually...meaning you use the standard 50ohm coax to each antenna, tune it, then hook up the 75ohm harness assembly and check again. If the SWR's are high, likely one or both of these things are the problem;
1.) spaced incorrectly causing reflection (or fighting each other's signal)
2.) 75ohm harness has a problem.

Hope that helps some.
;)

Basicly I agree here. Except I have always herd antennas need to be 6' apart, not 8'...If it were 8', then only Hummer's would be able to run duals!

And you must use a 75ohm co-phase (RG-59) coax harness.

[Rex_foxhound]

I just did some research and 1 full wavelength is 35.906 feet or 36 feet. So a 1/4 wavelength would be 36/ 4= 9 feet or 108 inches.

Hope that helps with something.

[Rex_foxhound]

Here's the link.
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Very helpful site.