High gain AM/FM automotive antenna?

Moab

Moab

TJ Expert
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Just looking for a stock replacement mast (Hopefully shorter.) that screws into my Jeep Wrangler TJ's antenna mount. I think it's the standard thread pattern. Something like this. But that will improve the gain of my radio - to the degree that it's worth the extra money? Is this not possible? I'm not seeing anything on the net. Except a shorter one with the SAME reception as stock. https://www.amazon.com/dp/B01M5JK8E2/?t ... rg-20&th=1 Or if I mount an extra antenna can I get better AM/FM reception? And/or would I do better with a handheld device and a high gain am/fm antenna for that? I have GMRS radios. Don't recall if the mast is replaceable. But I think it is.

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The reason you aren't finding any high gain shorter antennas is that typically antenna gain is a function of antenna length for these whip antennas. There are some tricks they can do to lower the height a little as you've come across but don't expect better performance out of those. I'd recommend sticking with the stock antenna or playing around with taller ones
 
mikalcarbine said:
The reason you aren't finding any high gain shorter antennas is that typically antenna gain is a function of antenna length for these whip antennas. There are some tricks they can do to lower the height a little as you've come across but don't expect better performance out of those. I'd recommend sticking with the stock antenna or playing around with taller ones
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I'm familiar with antennas. But I'm not even finding any longer ones that are high gain. Weird. You'd think someone would make something like this. There are of course ones from China that make all sorts of claims. But...

I think I might be able to find one for my handhelds. Maybe I'll just settle for that.
 
You're not going to find a shorter antenna that will outperform the OE factory antenna. Period. Even antennas with active amplifiers that require a source of power are not all they're cracked up to be... they amplify the noise as well as they amplify the signal.

I'd stick with the OE whip antenna, its extra length is what gives it its better performance than any of the shorter "more stylish" stubby antennas.

About the only thing that can added better reception is a better receiver. Some are definitely better than others at making weaker signals more listenable. And once FM signals start getting weak, there's not much that can be done with them since that issue is usually due to its line-of-sight characteristic that makes it more prone to being blocked by obstructions like hills, buildings, mountains, etc.
 
For anyone pulling up this thread later. Red Dog turned me onto this AM/FM/CB antenna for $17 plus connections, mounting plate and wiring. (I'm sure there are others. Have not researched stand alone antennas for this issue.) It's a 3' or 4' antenna that has to mount to a full size antenna mount. It won't replace your stock antenna. I guess you could delete the stock antenna or go with a snubby. The 4' gets better reception according to the seller. And needs heavier wire run to your head unit. But it does pull in stations from much further away. Thanks Red Dog! Added to the do to list. Red Dog says he's pulling in stations from 120 miles away. Not sure of the ground or building clearances. But that's good news either way.

https://www.wearecb.com/firestik-am-fm-antenna.html

Here's Red Dogs build thread. It's mentioned in his first post. https://wranglertjforum.com/threads/red-dogs-revival-thread.17467/
 
Be wary of claims on antenna performance for AM/FM car radios. You're not going to get good reception from FM stations from 120 miles away in your car or Jeep. AM stations at that 120 mile distance can be received with the factory antenna. I regularly listen to a Los Angeles AM news radio station here in San Diego and it's probably 130 miles away from where I live and drive. It comes in fine in all of my cars plus my Jeep with their standard factory antennas, I listen to it more than any other station. :)
 
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Jerry Bransford said:
Be wary of claims on antenna performance for AM/FM car radios. You're not going to get good reception from FM stations from 120 miles away in your car or Jeep. AM stations at that 120 mile distance can be received with the factory antenna. I regularly listen to a Los Angeles AM news radio station here in San Diego and it's probably 130 miles away from where I live and drive. It comes in fine in all of my cars plus my Jeep with their standard factory antennas, I listen to it more than any other station. :)
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Well REd Dog reported that he's at least getting stations in places like his garage where he could not get reception with his stock antenna before. So it has some performance gain. Either that or his original antenna was hooked up poorly. I'm no radio professional. But I've run scanners for years. And I've got a broad spectrum YAGI that could be deployed if the need ever arose.

That larger antenna with alot more wire has to have some benefits. I have a well respected hand held emergency SW/AM/FM hiking radio with a big long portable antenna extension. And it pulls in alot better with that added length of wire. I know the antenna has to be tuned for that freq. But it's worth a try. Especially if I'm going to mount a CB anyway. And if not, I least I have a halfway decent CB antenna for $17. Either way the wire and mount installation is going to be alot harder than the antenna installation itself. So I can always switch it out later if its a fail.

But I'll continue to look for similar antennas and reviews. Thanks for the tips. I'm wary like you are when it comes to electronics. Trust me. :)

EDIT - Just reread the description and nowhere does it say CB reception. So we'll see. One mark against it.
 
One thing to know, from a guy who built his first 15 meter dual element beam ham antenna as a kid in 1964, the correct antenna length is important. Adding height improves performance but just adding length by winding more wire around a fiberglass stick can actually reduce an antenna's effectiveness by detuning it.

For the 88-108 MHz FM radio band, the correct quarter-wavelength antenna length for the mid-point of that band is 31 3/4". That's the most common length for automotive car AM/FM antennas. If you measured your TJ's factory antenna length, you'd find it's just about that exact length including its mount on the tub. Having that exact quarter-wavelength length helps it receive weak FM radio stations better. AM stations are strong enough that length is not as critical.

Not to mention that spiral-wound antennas like that Firestick have a significantly lower bandwidth than when they're not spiral-wound. Spiral winding it can give it the required length compressed into a shorter physical length but that reduces its bandwidth, which is its ability to perform well away from the frequency its length was cut for. I'm just saying that particular Firestik antenna may not provide the boost you are hoping for.

And that little short antenna at your https://www.amazon.com/dp/B01M5JK8E2/?tag=wranglerorg-20 is all hype with poorer performance than the factory antenna provides. It absolutely will not perform as well as the stock antenna does. Forget all its marketing hype about it using copper vs. steel or aluminum, it makes no difference in that application. It only says "Reception Guaranteed" which is a pretty laughable guarantee. A wire coat hanger can provide reception. Nowhere does it guarantee anything better than that, it only compares its performance to other short antennas... not the factory antenna whose performance it absolutely cannot come even close to. You have to read between the lines on gadgets like that.

I worked in the HF/VHF/UHF communications field and took care of large antenna farms plus transmitter and receiver sites. I designed (a few), built, and erected many antennas including maintaining military and commercial antennas. I even had to erect dipole antennas by myself all over Vietnam for a medical evacuation HF (10 MHz) SSB radio network in 69-70. I'm still active with radio communications with a general class ham license with a multi-band HF antenna I made. Antennas and their designs is something I have a fair background in.
 
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Hey Jerry. What about a high gain antenna for a scanner in the am/fm band? Would that pull more stations in? My broad spectrum YAGI would do it. But something portable would be nice.

I gotta pull my scanners out again. And start playing with them.
 
moab said:
Hey Jerry. What about a high gain antenna for a scanner in the am/fm band? Would that pull more stations in? My broad spectrum YAGI would do it. But something portable would be nice.
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Generally speaking, high-gain antennas are directional so they have to be pointed toward the signal. For omni-directional vertical antennas that are suitable for scanners, some have gain but I really don't know much about scanner antennas so going to a scanner website like Scannermaster.com would be a good way to go. Keep in mind that VHF/UHF signals are strictly line-of-sight so they don't travel far when there's anything in the way... curvature of the earth, hills, mountains, buildings, etc. all get in the way of them.
 
pagrey said:
Also just in case anybody cares, Chrysler factory radios have really good tuners.
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I can vouch for this...the stock FM tuner in the stock radio is definitely better than my cheap and more recently made $100 Kenwood aftermarket radio. A little disappointing!
 
This is an old post I know. Figured I chimed in with something not mentioned. One of the things I did to really improve the reception (from just three stations to full range) in the TJ was to clean up the connector and the inside of antenna base (looks like they're both the stock 1997 part that came in the Jeep and was very corroded on the cable end).

The little female end was a bit loose, and I tightened it Adding a proper ground to the unit radio also improved the clarity of the reception(grounded the head unit frame with a wire and a spade connector so that I can remove it easily if need be). Both motor on and off(same signal, but tested it anyways) I would love to find the antenna base connector in new form to reterminate the antenna cable and make it all better (was really rusted on the cable tie-in end, not so much on the inside of the antenna base.

Without spending any money and just fifteen minutes of my time, I am now able to listen to local stations and from NYC(about 30 miles south), with perfect clarity, which I was not able to do before. Side note, today has been overcast and foggy and humid. I am sure on a clear day it will be much better.

To anyone looking to improve reception, check these things before spending your hard earned money first.
 
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