I am a novice and just learning about HAM. I am studding for the test and putting together a system in my Land Cruiser. I have a yaesu ft-2900r. I am trying to decide where to mount my antenna. My best choices for mounting locations are the front fender, rear hatch lid edge, and the roof. I would like to use the roof but run into a few problems. The primary concern is that i have a full length roof rack that i use for kayaks and pelican cases. I could easily use the very center of the roof. It is usually clear with the boats on the sides. the rack is made out of 3/4 inch tubing and sits about 4" above the roof. If i mount in the center with a something like a magnet mount will the roof rack interfere with the signal?              

I dont want to drill a hole but other than that i have a lot of roof options. I can do magnet mount, mount it to one of the rack tubes or fab up a mount. It would be no problem to make a small square plate between two of the tubes to mount to.

I just think at times that i am over thinking this. I could mount it on the front fender or rear hatch and let it just be a bolt on ready to go. Will the benefit of getting it up high on the roof really give me that much better signal?

Roof mount it.  The vertical part of antenna is only half of the antenna in theory, the metal roof is the other half.  The ground plane will help you very much..  The mag mount will work fine and you can move it out of the way if needed.  Google ground plane for some added info.  This is why a vertical hf antenna should have radials..   If it is possible, study the general some and take a chance on the free test after you get your tech test knocked out.   You are allowed to to take the next test for free.   Congrats on studying and dont hesitate asking questions.
The roof rack will not be an issue..
Ps.  Check out hamradio360 podcasts..  Will help you as a new ham with some of your questions..

Prosise

Thanks. Any recommend actions for antenas and mounts? People I talk with like the Larson 150 and comet sbb1 or sbb2. Any opinions?

I have had great results with a COMET-NCG SBB-5 dual band.  I just use a 5" magnetic mount.  Just don't make the same mistake I did by running the coax under the luggage rack and not being able to remove the mag mount if you wanted to run through a quick car wash.  I had to re-run mine.  I've been able to hit my 440 repeater from almost 100 miles away with this antenna and my Kenwood V71a.

Yes.

Yes the roof rack will interact with the antenna, as would any other conductive material.

The interaction will almost certainly be something that will never create a problem in actual operation as far as the rack itself.

For an antenna I would suggest a Sti-Co flexi-whip, simple 1/4 wave antenna made with a nitinol antenna element so is flexible and essentially unbreakable. Something on your rack slides into it, no problem.

Check out this website, all info on mobile installations.

K0BG Mobile Operations

I ran a mag mount in the center of my roof from about 2008-2016, then about 6 months ago went to a fender mount.  I like it so much better.  I never have to worry about clearance when I pull into a drive through or parking garage, and I can swap my low profile antenna for my big Diamond without having to crawl up on my running board and rear tire.  I also don't have my paint being ruined by trapped moisture and abrasion from the mag mount.

I haven't noticed a difference in performance, and my SWR is 1:1.3 with the antenna mounted on the fender.

Dallas, thanks for the info. i will keep that in mind.

But i just picked up a magnet mount locally. I will mount it on the roof and run a Comet SBB1 half the year while in Atlanta/east coast. Then something longer when in WY the other half. I dont half to worry about paint on the roof. my roof is Monstalined. Hopefully it is not too thick for the magnet mount to work well.

No effect that you would notice in operation. I have a quarter wave mag mount sitting a few inches from my roof rack, the SWR is good, and it gets out well.

Incidentally, it's "ham radio", not "HAM". It's not an acronym. I dunno where that HAM crap got started, but it's misled a lot of noobies.
As to exactly where the term "ham radio" came from, it's one of the great mysteries of the hobby. However origins of the Wouff Hong and Rettysnitch are documented.

Any idea on how the one on top was used? My imagination is pretty vivid.

They're nonsensical tools that have no function other than confusion.

In theory it should diminish performance.  In actual operation I honestly feel its hard to notice any true performance differences.

I will say that performance from a straight up 5/8" whip antenna mounted in the center of an SUV roof is pretty hard to beat in simplex, mobile to mobile operation through various terrain.

With that said I moved from a center mounted roof antenna to antennas mounted on my roof rack.  I prefer the durability factor, and like the roof rack utility and look.  Plus it gives me a good solid mounting point for a real CB antenna.  I like to have as many comm options as possible should SHTF, and that includes a CB.  For me I feel this combination works well, and its honestly hard to notice much, if any performance difference vs. my previous NMO center roof mount setup.

I am sure the roof rack does provide somewhat of a ground plane.  Obviously not as well as the center mount, but I will be dammed if I can notice much of a real world difference.

My old setup:











Current:













Actual noticeable real world operation difference = none.

Only difference I can tell is the looks, and I prefer the roof rack look...  Six to one half a dozen the other?  

It's working.

It's hard to say without knowing an exact antenna position in relation to the roof rack. It will most likely cause some de-tuning of the antenna.
It's best to attach the antenna to the  full size rack, with the coax shield properly bonded to the rack and the car's roof (if possible). Use a 1/2 Wave antenna if you can't provide a good connection to the groundplain (roof rack &the roof).
I use a lip mount for a VHF/UHF antenna on my SUV. So far it's been working relatively well. I made sure to use one of the mounting screws to bond the antenna base to the rear door hatch.

The problem I always ran into was getting the coax inside of the vehicle nicely (and in a manner which doesn't leak water). I don't think I have the progression my XJ went through anymore. Started with a Yakima OEM rail mounted rack. Threw that off (never could get it to properly secure) by accident so I patched the damage and dismantled some old gutter mount ski racks for the cross bars. After a little while I noticed signs of the rails bending so I built some new gutter mount rails. Ran a 1/4 wave on the rack for 2m. About the time started getting serious about radio I decided my old XJ was just struggling too much with the rack on it (OD was useless and the transmission was a better in-cab heater than the OEM one from all of the shifting). Pulled it, built a rear carrier for my spare, added an antenna mount for a dual band antenna to that, drilled the roof for an APRS whip and added a fender mount for the CB. Picked up 3 more MPG and the transmission doesn't shift as much anymore. Now I'm abandoning the dual band setup and going straight to the VHF whip on top. Reassembled the ski rack and it goes on and off seasonally (cause I don't feel like driving my pickup in snow when I've grown up driving my XJ in it).

But I'll second the Nitol whips (Sti-Co Flexiwhip). Can't break them and who cares what you with them.

And here I always thought a good old XJ was tougher then the modern Patriot.  It does affect my mpg a bit, but no to much.  Any ways I might look at a couple hatch lip mounts here come spring time.

-For the record I have owned two XJs, Two TJs, and one ZJ prior to my current Patriot.

Well, something about 10 ply 31x10.5's, a 4" suspension lift, and 3.55 gearing mated with the general aerodynamics of a brick don't make them the best highway vehicles when setup that way. Way more comfortable to drive in compared to the Samurai it replaced (with a 8" suspension and 2" body lift firing on 3 of the 4 cylinders). Don't get me started on the KJ's though…since they were badged as Cherokee's overseas…never in my life have I had trim panels hit me in the face going down the highway until I drove one of those (it was only 2 years old at the time). It really made me respect the screwed on metal trim of the XJ's headliner.

I've literally grown up in the XJ platform. My mom had one when I was younger. My dad's company cars were ZJ's at the time. Haven't had the joy of owning a YJ or TJ but I do have a CJ-2 stashed away…in need of resto. Also spent some time in high school tinkering with a MB someone put a hurricane in but that's a different story.