Best antenna for a car with a mostly glass roof?

[arudlang]

Hey all!

I'm looking to do a super clean, high quality CB radio+antenna install on our 2020 Jeep Cherokee for basic road trip communications and local chat when we are at our favorite campsites and off-road trails & parks.

I got an unbelievable deal on a President Electronics "Bill" radio that was bundled with their "Wyoming UP" antenna (click here to see it) which is a magnetic mount 1/4 wave about two feet tall. It was $31 cheaper to order the radio bundled with this antenna vs buying just the radio itself (and no, the bundled deal is not still going, believe me I would have bought more than one set if I could have!)

So, the Wyoming Up looks like a decent stealth antenna for our sleek, all black car BUT I am concerned that its not going to be able to function well because our car has an almost entirely glass roof up top. There is one thin strip of actual steel at the very back of the car, and while it is enough metal for the magnetic base of an antenna to stick I am guessing its not enough metal to properly act as a ground plane for the antenna to work decently.

Here is a crappy picture of the problem:



My other issue is that often times on road trips we have a Thule cargo box up there which kinda interferes with that area as an antenna location:


So... as grateful as I am for the sweet deal on the bundled P.Bill radio and Wyoming UP antenna, I'm suspecting that what I really need to do is to order up a decent two foot no-ground-plane antenna for this particular car. Would you guys agree?

I figure with a nice NGP antenna I can fab up a nice bracket to put it towards the end of the Jeep's crossbars and make it such that it will rotate/swivel down on its mount if it hits anything, be easy to put up and down for garage doors, etc. I would probably go for the spot closest to the driver's door so its easy to step out or maybe even just roll down the window and swing the antenna down to clear a garage door. I'm sure it will be on a spring too just in case a certain someone forgets... I could also look into a hood or tailgate mount which wouldn't be as good on height but might look nicer overall. A lot of Wrangler owners seem to get away with a fiberglass antenna mounted at the back, half under the profile of the roof.

I know I can just *try* the Wyoming UP antenna when it arrives but I don't really like to waste a ton of time with something I know is likely to end in failure. I don't want to spend a bunch of time doing a nice install on the dash of the radio and have it not work worth a darn because the antenna is incompatible with the car. If I need to run a special NGP coax and get it cleanly hidden and routed I'd rather do it up front. My shop hours are borrowed right now in someone else's building and that time is pretty precious to me, being a busy person.

It really won't bother me to have the Wyoming UP antenna sitting around as a spare, because I'm putting together loaner car kits for my friends and family when we are on multi-car road trips so that would be an excellent antenna to have for a temp loaner. Takes up less space and less of an eyesore than a Tram 703 centerload.

Interested in people's thoughts and suggestions, personally I'm leaning towards placing an order for a nice two-foot fiberglass NGP antenna kit.

Instant Edit: I went ahead and ordered a two foot Firestik NGP kit (FG2-648) because it was the last one in stock at a $50 price point and I didn't want to miss it. I will be able to use it either way on my golf cart or something I'm sure, but it's hard to imagine its not going to be a better choice vs the Wyoming UP for our Cherokee.



What would you folks with more experience suggest for this car? I've got options now.

 

[KC3ECJ]

If you're not using more than stock watts, what about a lip or right angle mount by the hood of the vehicle?

 

[mmckenna]

What would you folks with more experience suggest for this car? I've got options now.

A 2 foot tall loaded 1/4 wave antenna is going to have pretty awful efficiency. If you are just looking for a cheap/easy short antenna that will let you hear very local traffic, then the included antenna is as good as anything else. If you want better performance, the antenna is going to need to be longer. You can't stuff 108" into 24" and expect it to work well.

The 2 foot tall no ground plane antenna probably won't result in any noticeable differences. Still the length issue. The magic in the 1/2 wave antenna isn't just in the antenna, it's in the feed line that becomes part of the antenna. You would just be moving the 'other half of the antenna' down into the coaxial cable.

No passenger car is going to have enough ground plane for a perfect CB installation. The vehicle just isn't wide enough. So you do the best you can with what you have, less than ideal ground plane included….
You do have some ground plane to work with, and while not ideal, use it to your advantage. Set the antenna in the center (left/right plane), that'll reduce it's directional effects as much as you can. Mounting the antenna off to one side, either on the roof rack or the fender is going to make it directional, which may or may not work to your advantage.

Also, use a taller antenna if you can. Not suggesting a 108" whip, but you can do pretty well with a 4' base loaded whip if you do a good installation. I'm a fan of the Larsen NMO-27, Laird C27, etc.
I personally really prefer doing permanent NMO installs. I know not everyone is, that's OK. If you want to try the mag mount, do it.
I'd probably try it centered on the roof either in front of or behind the sun roof. My preference would be in front as that would give you some more ground plane around the base. Might also work with your roof top cargo box.

Benefit of the NMO mounts (either permanent or magnetic) is that it gives you a common platform to use for other antennas if your interests change. There are a lot of really good NMO antennas for CB, ham, scanners, GMRS, MURS, etc.

 

[arudlang]

Taller is probably gonna be a no-go unless I can mount lower on the vehicle which starts to offset the purpose. Like I said, looks do matter on this car. It's not a clapped out 300,000 rust bucket, it's a sleek new rig with almost no miles on it.

There has got to be some performance difference between a 2 foot magnetic antenna that expects (but won't get) a ground plane vs the 2 foot NGP antenna with the ground plane in the coax, right?

I assume, perhaps incorrectly, that there is no point in using anything other than a NGP antenna on a car like this. There is no exterior sheet metal anywhere on this car bigger than a cookie sheet except the hood and the doors. And there is no flat metal anywhere. Every bit of this car has shape and contour to it. Nothing on this vehicle looks like it could remotely function as a proper ground plane. The roof is 95% glass, and I can't stick an antenna in the middle of a hood that is steeply slanted and contoured anyways so... Seems like it's gotta be NGP, right?

If I put a 4 foot regular Fiberglass antenna on the bumper, it's "longer" but still has no counterpoise to push off of. Not going to work so well, as I understand it(?) if it's an NGP setup with the special coax then I only worry about whether the body and glass of the car blocks the signal in one direction. But I am here to learn.

I don't want to miss an option that gives me 2 miles more of range if I can help it, provided I can do it within the appropriate aesthetics for the vehicle in question. That means no redneck 102 inch steel whips on the sleek suave alfa romeo inspired Cherokee. That's just the requirements I'm working under, I didn't make them I just have to operate within them 😉

 

[mmckenna]

You do have a ground plane to work with. The sides of the roof are metal, the hood is likely metal. Not a "perfect" ground plane, but no road legal vehicle has a perfect ground plane on those frequencies. If you wanted a perfect ground plane, you'd need about 8 feet of metal in all directions under the antenna, including out to the sides, so a 16' wide car. Not going to happen.
So you do the best you can. Some ground plane is usually better than none. Mount the mag mount antenna that came with the radio and give it a try. No need to rush out and buy something new without at least trying it.
A no ground plane would be my second choice, but unless that money is burning a hole in your pocket, give the mag mount a try.

Either way, you'll need to figure out how to route the coax into the vehicle without damaging the cable or the weather stripping.

As for new cars, I've done a lot of permanent NMO installs on brand new cars, including a few that came to me straight from the dealer. A properly installed antenna will look and work better in the long run, plus you don't have to worry about coax cable routed across the roof and through a window/door. A properly installed NMO mount will not reduce resale value, but I can totally understand your wife being against it. But keep in mind, mag mounts can damage paint. Flapping coax laying across the roof can damage paint. Water leaking in around the coax through the door/window/rear hatch can do a lot of damage.

Pick your poison.

 

[slowmover]

Dump the box. It’s an affectation, not an aid. Hurts fuel economy and worsens cross-wind handling.

You’ve two exterior mirrors. Learn their use over the central piece inside. Load the interior to ceiling at rear.

You’ll do as you will, just don’t try to state their usefulness as it doesn’t exist. I was strapping “containers “ on station wagons nearly fifty years ago (we only had the left hand mirror).

Buying the other mirror was the solution.

Use dark moving pads or blankets to wrap or cover gear.

SUVs are pretty much worthless compared to an old-fashioned full-size sedan with a voluminous trunk when it comes to transporting family + luggage.

“Utility” doesn’t exist for these vehicles. Suitable for women who can’t understand tail-swing; who follow the front wheels around without understanding turns are pivots from the rear axle.

A trailer no wider and less tall than the SUV which fills the air space directly behind would be beneficial to transport AND fuel economy without presenting much side resistance to winds.

Others want to travel the roads with non-existent or severely degraded comms, it’s on them. The traffic volume and potential problems thereby are staggering these days.

Folks think metro-to-metro road travel is just an extension of their suburban bubbles. Couldn't be more wrong.

Expectations of services, conveniences and orderliness are severe misjudgments that false veneer is stripped away.

The CB which can reach in TX/RX is without peer. WAZE and G-Maps just trap a body with the other sheep. Are far too slow in response to immediate necessities.

The antenna system is king. That this isn’t built-in at factory to take advantage of Citizen Band tells you what your masters think of you. What they hope you won’t use.

Mine in the Kenworth is turned on thousands of hours annually. The effort expended is above and beyond what’s needed for a private vehicle, and won’t match one that’s well done.

You’ll note (anyone reading) that Americans have been trained to disregard this tool.

This tool needs to be of sufficient design (AM/SSB, in my opinion), and the supporting systems (power + antenna) have priority over any installed components (those can be changed).

“What I’m willing to tolerate”, is an emotional cop-out.

My take — for the very few men who get the nudge to install and use the means of communication (versus slave to services they don’t control) — is to step back and re-consider their impulse (which was not a plan, just a picture).

The nudge was not by accident.

A “coincidence” it ain’t


I’m around up to several hundred men with radios in a road incident, and one of only a handful who can be said to have reliable or optimal service.

The discussions among the few with “good” systems appear to take place without these others. Solving the problem after an accurate assessment. To the point where it’s as if the others can’t hear. Uncanny.

A three-mile double-lane backup of big trucks and only two-three of us on a detour to go around to thereby save ourselves an hour or more plus a TON of stress in losing momentum for our workweek (DIRECT effect on net pay) is typical.

That’s after the safety hazard of being trapped with no way out (just one vehicle catches fire it’s gonna get ugly in seconds).

Some can’t detour (details of work being performed), and others are literally not bright enough to read a map. But this doesn’t describe the majority.

I keep the (recommended) Commercial Road Carrier Atlas at hand. And know what questions to ask locals or regulars.

Being trapped in the wrong place at the wrong time? Just your bad luck as your surviving relatives said.

Citizen Band is a tool anyone from pioneer stock will recognize. It’s leverage.

The child’s toy hammer version won’t suffice.

.

 

[JoshuaHufford]

I'm far from an expert on this but after reading through this thread I wonder if you would be better off with a different license free band at a higher frequency that doesn't require such a large antenna for good performance.

I have 2 MURS radios and can usually get a couple miles easily with roof mount antennas on each vehicle. How much range do you need?

 

[arudlang]

Dump the box. It’s an affectation, not an aid. Hurts fuel economy and worsens cross-wind handling.

You’ve two exterior mirrors. Learn their use over the central piece inside. Load the interior to ceiling at rear.

You’ll do as you will, just don’t try to state their usefulness as it doesn’t exist. I was strapping “containers “ on station wagons nearly fifty years ago (we only had the left hand mirror).

Alright, you are pulling us into a tangent but I will entertain it. Going to have to disagree with you but there are good reasons why. The cargo box is an aid, a necessity, and a boon to our roadgoing efforts.

We cannot put the skis and snowboards of four people inside the cabin of our car. We will go, for instance, on a multi-state skiing trip with a couple friends in tow and so the rear seats cannot be folded down, and the primary "trunk" cargo space behind the rear seats is where we keep duffle bags and suitcases of clothing and things we avoid freezing like our traveling toiletries.

The rooftop cargo box can hold the skis and ski poles and boards of the whole group, along with boots and helmets and other bulky bits that are not cold sensitive.

Then consider a summer camping trip a state or more away, again take two friends along for the ride, the cargo box can hold our large tent which is 4 feet long even when folded up, along with a four foot folding table, some camping chairs, etc etc. Again we need the usual trunk space behind the second row for a sealed tote of food and some clothing and small gear.

The rooftop cargo box is of great use in many circumstances to us. True, we do not use it when we don't need to. Right now we have been just skiing my wife and I without anybody else, so the rear seats are folded down and the skis are laying there in the back of the cabin as I type. But the valid need does arise for the cargo box and I will not give it up. That box, that one piece of equipment, allows us to use a smaller, cheaper, and more efficient vehicle in a more flexible manner.

We could have bought some land barge like a Chevy Tahoe, and only fully utilize it's full cargo potential a few times a year on those trips, then burn extra gas and deal with its higher payments year-round while it's extra space is not needed, or, we can use this smaller car and give it a boost in cargo capacity when we need it. With the box on the roof we get lower mileage like a larger vehicle but we're not cursed with that lower mileage year-round for regular work commuting or shorter trips.

I feel quite justified in keeping my cargo box.

SUVs are pretty much worthless compared to an old-fashioned full-size sedan with a voluminous trunk when it comes to transporting family + luggage.

“Utility” doesn’t exist for these vehicles.

See above. We go on many cross-state trips each year for skiing, camping, etc. We flex its cargo capacity as needed and enjoy better mileage and its overall lower cost when we're just commuting locally with it. It is a good fit for us.

A trailer no wider and less tall than the SUV which fills the air space directly behind would be beneficial to transport AND fuel economy without presenting much side resistance to winds.

Funny you should say that, because I constructed exactly that type of trailer a couple years back for use on our biggest adventures. I built this trailer out of an abandoned boat trailer from the 60s. The body opens on both ends and is around 63 cubic feet of space, and has a top rack that can take the cargo box or other items while still staying below the roofline of our Cherokee. I retained the long boat trailer tongue and put a rack on it that accommodates four bicycles (for those summer camping trips where the friends ride with us). Being lightweight and within the airstream profile of the vehicle towing it, its a pretty efficient trailer that our V6 doesn't notice much pulling around (low gas mileage penalty) but it gives us a mountain of additional cargo room for gear, coolers, our friend's tents and whatever else.



(Side note, this is an older picture from before it was fully finished and the bike racks adjusted down to ride flat)

Again this falls under the notion that I could have bought some kind of huge 3-row Suburban or similar if I wanted mountains of cargo space (a few times a year) but by alternatively using things like my cargo box and/or my homemade trailer I get the space I need when I need it, and I revert down to a smaller, more efficient, and less expensive base vehicle for 75% of the rest of the day-to-day miles we put on it. Works out alright for me.

 

[arudlang]

I'm far from an expert on this but after reading through this thread I wonder if you would be better off with a different license free band at a higher frequency that doesn't require such a large antenna for good performance.

I have 2 MURS radios and can usually get a couple miles easily with roof mount antennas on each vehicle. How much range do you need?

I suppose if it was only ever for communications within my own groups of friends and family that would work, and that definitely is the primary intended purpose 90% of the time I would say for my mobile installs. I would like to be able to communicate with other people like truckers on the road and hear about road hazards and detours and such, as slowmover alluded to, but realistically is that going to actually happen and work out on the open road? I have no idea I guess until we try.

I like how common CB radio is and how easy it is to tell someone "hey, just go to our local farm and fleet store and pick up any CB radio you like and we'll be able to chat" (meaning, the equipment will be compatible.)

MURS is something I should look deeper into, but at first glance it looks like CB is still more prominent for on the road and its nice that I can chat locally to my home base station with it. I wouldn't mind adding more options to the mix though so thanks for pointing it out!

 

[prcguy]

I've done a lot of CB installs with sunroofs and their is not enough ground plane to provide a good match for most antennas. I would go for a trunk lip mount near the cowl on the hood. Something like a Larsen or other good quality base load with the longest whip you can find. A thin whip will not affect your vision out the front window as bad as a fat colorful Firestick.

 

[mmckenna]

MURS is something I should look deeper into, but at first glance it looks like CB is still more prominent for on the road and its nice that I can chat locally to my home base station with it. I wouldn't mind adding more options to the mix though so thanks for pointing it out!

MURS can be handy if you want to communicate just within your group. It's mostly an under utilized radio service.
Finding suitable radios can be a challenge. You won't find a good one at your local truckstop or farm store.
And you won't make random on-the-road contacts like you would with CB. Users that utilize MURS tend to enjoy having their own setup and not talking with random strangers, so CTCSS/DCS is commonly used. Your friends being able to find a radio locally/easily is pretty much out of the question. Mobile radios are not available on the new market, so you'd be using a hand held radio wired to a roof antenna and cigarette lighter plug. That gets old….

GMRS can be a wonderful setup. There are mobile radios on the new market, but they'll cost more than a new CB.
GMRS requires a license to use these sorts of radios. But again, most users like the ability to use CTCSS/DCS to keep communications between themselves, and making random contacts on the road is difficult at best.

From what you describe, CB is a good resource. If you wanted to get fancy, wait for the newly allowed FM capable CB's to hit the market and you'll get some better audio. CB is much more useful for random contacts and road info. Drawback is the larger antenna and colorful language and toy noisemakers that people like to use.

Nice trailer, by the way. Looks like a good setup.

 

[mmckenna]

I've done a lot of CB installs with sunroofs and their is not enough ground plane to provide a good match for most antennas. I would go for a trunk lip mount near the cowl on the hood. Something like a Larsen or other good quality base load with the longest whip you can find. A thin whip will not affect your vision out the front window as bad as a fat colorful Firestick.

I ran a set up like that on a full size pickup back in the early 90's. NMO-27 and a fender bracket mount. Worked well enough for me for local CB use. The antenna didn't interfere with my view, even with it on the drivers side. It was down low enough that parking garages and low tree branches were not a problem. Ultimately I moved it to the top of the cab and was happier with the final product.

Might be a good solution.

https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=264_266_291&products_id=1125

This NMO mount has a better sealing design on the bottom. You don't want to use the standard NMO mounts since they are not sealed on the underside as they are designed to be mounted through the roof where the coax connection is warm and dry. I'd recommend adding a piece of marine grade/adhesive lined heat shrink over the coax cable where it enters the mount, or at least make sure you seal it up with some silicone.
You can order that mount with the connector of your choice. You can have them install a PL-259 to match your CB, but routing that big connector can be a challenge. You can have an FME style connector installed, which is much smaller, and then use the FME to PL-259 adapter to connect to the CB. It's an option if you don't feel comfortable installing your own coax connectors.

Larsen FP - FME Male Adapters

FME Male to PL-259 (UHF Male) Adapter

www.theantennafarm.com

The mounting bracket is easy. You'll just need to drill a couple of small pilot holes into the inside of the fender between the fender and hood. 3 stainless steel sheet metal screws hold the mount in place:

PCTEL Maxrad BTGB34 - NMO Brackets (No Cable)

PCTEL Maxrad BTGB34 NMO Brackets (No Cable) - Manufacturer: PCTEL Maxrad; Model #: BTGB34; Product Description: L Bracket; Product: For NMO Style Antennas

www.theantennafarm.com

And the antenna:

https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=191_192_194_447&products_id=699

I've had one of those for 30 years, still works like it's new, although I don't use it often anymore.

Some have reported good results using a separate NMO-30 coil with a longer whip, but to do that you'll need the right tools to tune the antenna yourself. The NMO-27 comes with a cut chart that covers CB, the NMO-30 won't.

 

[slowmover]

Alright, you are pulling us into a tangent but I will entertain it. Going to have to disagree with you but there are good reasons why. The cargo box is an aid, a necessity, and a boon to our roadgoing efforts.

We cannot put the skis and snowboards of four people inside the cabin of our car. We will go, for instance, on a multi-state skiing trip with a couple friends in tow and so the rear seats cannot be folded down, and the primary "trunk" cargo space behind the rear seats is where we keep duffle bags and suitcases of clothing and things we avoid freezing like our traveling toiletries.

The rooftop cargo box can hold the skis and ski poles and boards of the whole group, along with boots and helmets and other bulky bits that are not cold sensitive.

Then consider a summer camping trip a state or more away, again take two friends along for the ride, the cargo box can hold our large tent which is 4 feet long even when folded up, along with a four foot folding table, some camping chairs, etc etc. Again we need the usual trunk space behind the second row for a sealed tote of food and some clothing and small gear.

The rooftop cargo box is of great use in many circumstances to us. True, we do not use it when we don't need to. Right now we have been just skiing my wife and I without anybody else, so the rear seats are folded down and the skis are laying there in the back of the cabin as I type. But the valid need does arise for the cargo box and I will not give it up. That box, that one piece of equipment, allows us to use a smaller, cheaper, and more efficient vehicle in a more flexible manner.

We could have bought some land barge like a Chevy Tahoe, and only fully utilize it's full cargo potential a few times a year on those trips, then burn extra gas and deal with its higher payments year-round while it's extra space is not needed, or, we can use this smaller car and give it a boost in cargo capacity when we need it. With the box on the roof we get lower mileage like a larger vehicle but we're not cursed with that lower mileage year-round for regular work commuting or shorter trips.

I feel quite justified in keeping my cargo box.




See above. We go on many cross-state trips each year for skiing, camping, etc. We flex its cargo capacity as needed and enjoy better mileage and its overall lower cost when we're just commuting locally with it. It is a good fit for us.



Funny you should say that, because I constructed exactly that type of trailer a couple years back for use on our biggest adventures. I built this trailer out of an abandoned boat trailer from the 60s. The body opens on both ends and is around 63 cubic feet of space, and has a top rack that can take the cargo box or other items while still staying below the roofline of our Cherokee. I retained the long boat trailer tongue and put a rack on it that accommodates four bicycles (for those summer camping trips where the friends ride with us). Being lightweight and within the airstream profile of the vehicle towing it, its a pretty efficient trailer that our V6 doesn't notice much pulling around (low gas mileage penalty) but it gives us a mountain of additional cargo room for gear, coolers, our friend's tents and whatever else.

View attachment 114420

(Side note, this is an older picture from before it was fully finished and the bike racks adjusted down to ride flat)

Again this falls under the notion that I could have bought some kind of huge 3-row Suburban or similar if I wanted mountains of cargo space (a few times a year) but by alternatively using things like my cargo box and/or my homemade trailer I get the space I need when I need it, and I revert down to a smaller, more efficient, and less expensive base vehicle for 75% of the rest of the day-to-day miles we put on it. Works out alright for me.

Then none of this is “coincidence”. Leave roof carton conceptually “out” till antenna problems solved.

Other radio services to consider need their own mounts.

Comms given priority as trailer already exists. (Change long tongue to short sans bikes).

.