Antenex Phantom antennas

[va3wxm]

Anyone have experience with these guys?

Are they good? Bad?

[nmfire10]

UHF, 800, 900, + all work fine. I've never used VHF however I hear nothing but horror stories about them for some reason.

[Tom in D.C.]

The VHF units I have tried have a usable transmit bandwidth of
1 (that's ONE!) mHz. I think that answers the question, or at least it
does for those of us who need more than that.

[ANB_Medic]

I have used an 800 Mhz version for the last 5 years, and am in love with it. Very low-profile too.

Todd

[k2hz]

The VHF units I have tried have a usable transmit bandwidth of
1 (that's ONE!) mHz. I think that answers the question, or at least it
does for those of us who need more than that.

The narrow VHF bandwidth is characteristic of that type of low profile antenna and is not uniqe to Antennex. The similar Comtelco and Radiall/Larsen antennas come factory tuned for a 2 MHz bandwidth.

The Antennex Phantom is field tunable for a claimed 1 MHz bandwidth. I prefer the Radiall/Larsen to avoid the problems of attempting to tune in the field. My application has been on railroad passenger cars where tuning would have involved climbing on and off of the car roof many times while adjusting and checking the tuning.

I don't think there is anything wrong with the Antennex, you just need to be aware of its characteristics.

[va3wxm]

Cool thanks for the replies.

A buddy of mine is looking to get 2.4 GHz one to put on the car for HSMM work. Since it's technically his wife's vehicle he has to tread lightly for antenna installs.

[JohnWayne]

The older generation VHF Phantoms do have a fixed 1.5MHz bandwidth that is tunable. However, the new VHF Phantom Elites have a fixed 5MHz bandwidth. So, they will work across the entire 2m band, or 150-155MHz, 155-160MHz, etc with absolutely no tuning required.

I put 142-160MHz tuned to 154.680MHz on the analyzer, and I also did the same for the new Elite 150-155MHz version. The VHF Phantom results can be seen here, and the VHF Phantom Elite results can be seen here.

The 2.4GHz version works pretty well, especially in urban or campus environments.

Jeff

[Birken Vogt]

I am using a standard TRAT on high band right now. Our trunking system inputs spread across 2.5 MC of bandwidth so I used a network analyzer and RLB to ever-so-carefully tune the TRAT to a little more than 2:1 SWR on each end. Definitely outside of its published spec. It works OK within about 5 miles of the repeater but outside of that, in any holes, etc. it really starts to drop out. I call it a "rubber duck for mobile"

If one thing should give you a clue it is that they only allow you to transmit for 60 seconds I think which means a considerable amount of signal is going into loss and heat inside the antenna.

When recieving, when it finds nulls they are very sharp and deep because of its small size. Its transmit performance seems to be pretty dismal as well.

Bottom line is, I wouldn't use it unless a customer specifically demanded it and then after explaining how much of a compromise it is.

The Phantom elite looks interesting though, I wish I had bought one of them for testing instead of the regular one.

Birken

[usmcguttentag]

I am using a VHF Phantom, it's no good... It there is no advantage for a mobile user with this application.

[JohnWayne]

The main advantage of the VHF Phantom is the size. They are meant for urban envrionments where the signals are strong and a low profile is needed. A typical application would be a wrecker driver who is going in to parking garages all day, or a transit bus with an already high profile. A normal whip antenna doesn't last very long in these applications.

If you don't fall in to the above profile, then you are probably better off with a quarter or 5/8 wave whip, especially in rural areas.

Jeff

[usmcguttentag]

Jeff, you are right on that... I agree it has it's applications, more so for a city operation. But take a state or county unit or rural fire department, I would agree, go with the whip... -Scott

[firemedic4]

I have 6 on my truck and love them 2-vhf.2uhf and 2 800 mhz

[kb3jkp]

whats wrong with a 1/4 wave?

so what if it gets whacked... it springs back into position..

[Birken Vogt]

I totally agree with the parking garage assessment, a 1/4 wave, if it scrapes the roof, will break every flourescent light bulb in the place. Also getting whacked is one thing but getting hit over and over, day after day will break any antenna. And often the drivers are not smart enough to notice or report it either.

Birken

[thebigphish]

not to mention, that if you hit it low enought down on the length, you'll just shear or snap it off...and in a day in/day out environment like a wrecker in a parking garage or a low clearace environment, you're talking like a 10 day lifespan.

[irsa]

Not sure what brand we use, can't read mine as some one built up around it with black caulking compound, or what frequency. But they seem to work all right around town, I'm a delivery driver. I don't miss scrapeing the whip along low level ceilings, or scareing the girl at Maccas drive through. Haven't tested it yet out of area, although the MDT that uses it had a fit the other day in the city between 2 buildings. Personally I'm undecided, if it was my van I probably would have stuck with a whip, or 6.

[kb3jkp]

I"m talking about a chrome dome, VHF 1/4 wave,not the spring loaded antenna's...yeah..it might get that "swept back" look after a bit,but ...geez.... you'd be better off mounting a 1/4 wave on the lip of the hood.....if you're that concerned about height...

[wd9cms]

I use a STI-CO Industries FLEXI-WHIP for VHF mobile it is a 1/4 wave antenna and can handle 150 watts. It is very flexible and you can drive in and out of garages and other low overhangs with no problem. It is also broadband and very well made.

[mmtstc]

I would agree that the VHF Phantom antennas are crappy, i much prefer to have a 1/4 wave on my roof, but it si better than nothign when it is your only option. when is have my kayak on top of my car, the 1/4 wave is not a feasable option, so the low profile is great for thsoe tiems when i really need low profile

[Screwed]

the VHF phantom looks like a big can of beans its actually not to bad. mine sits center with a UHF/800 phantom on each side i also have a 450 and 800mhz stick antenna with 2 trunk lid mounts on either side allthough i am looking to mount those on the trunk and not the lip

[kielhofer]

If you do tune up a VHF phantom you HAVE to set the power output to 5 watts maximum. Infact I would tune any of those with minimum power levels.

These suckers get hot when transmitting, I tried tuning one up using a Motorola "diddle stick" and the unit got so hot it melted the plastic.

As for the 800 MHz phantoms, we tested the Maxrad against the Antennex and the Maxrad had better performance. The SWR was lower in the trunked portion than the Antennex.

I also wonder about their 3dB MEG (mean effective gain) specs; what does this actually mean?

Craig

N9NBO
GROL & GMDSS O/M
with radar.

[apco25]

Maxrad MLPV series antennas work very well. I use them extensively on installs for UHF, 700, 800 and 900. VHF gets a simple black or chrome 1/4 NMO whip. Nothing works better. Don't waste your time on the low pro can antennas on VHF unless you have a very specific application and a high signal quality coverage area to work with.

[W1HVN]

One more opinion to log,

I use the 800 for rx, 902-928, VHF, UHF, and Special order 225MHz on the Expedition.

Here are my findings over the last year,

The UHF, 225MHz, and 800/900 all work Great. All equal or greater to a 1/4 wave, and on UHF compared to a 5/8over5/8 and found little to no difference. The 800/900 I compared to the Laird 3db gain sticks, and found again a small difference on the stick (improvement) but you really had to pay attention to the small differences.

The 225 comes special order from Laird, and has a very "hokey" tuning design. They send you a metalized black sticker you have to shave off and apply to the top of the antenna to tune it. C'mon guys, you mean you couldn't have invested in a tuning pot? So yes, mine has the sticker on the tp tuned for 222MHz, secured with black electrical tape to secure it which i replace every month or so for preventaive mx. Works well, really cheezy design. Good news is only cheezy hams like myself use them, so it's ok

The VHF I only use for APRS applications, as the bandwidth is 500 khz either side of tuned freq. It is slaved to a single freq radio that only works for position beaconing. This is about the only application I can think of that would work with this unit, unless you have a department that uses freqs allocations that fall pretty close to each other and use little to no interop with othr VHF agencies.

I removed the roof rack from my Expediton, which has a metal infrastucture beneath the plastic, and it made somewhat of a significant improvement to the radiation pattern and subsequent performance.

Hope this helps those choosing these, in summary I give them an 8 out of 10, def go for the upper bands though, better than a unity gain stick all day long.

[Mraudio]

I have had huge success with these antennas on 800 Mhz for the counties MDT's. We had tried everything then I tried these. The next week I had everyone from the department knocking on the door wanting one.
That made me buy a UHF one and I can say that the radiation and capture effect from these antennas is superior over a 1/4 wave whip as they are circular in polarization. They have just about as much horizontal as vertical plane. This design in effect helps null out multipath and phase normally associated with the higher smaller wavelengths. I noticed great improvement in coverage. Just my two pennies worth.
Jeff

[alex]

I have used the Phantom's going on almost 4 years now and never had a problem with them. I have a VHF one which I use for just normal rx, not a lot of transmit. The power in the radio is turned down to ensure that I'm not going to melt the thing. I am in an urban area (Aka NYC metro area) and having a truck that is 6'2" going in and out of garages I can't really have whips as they hit the I beams at the garage at the spring, bending them into the roof.

If I'm doing anything that does not require driving into or out of garages, I have a nice spring mounted antenna I pop up there.

-Alex

[Quick[US-OK]]

I know the thread is old, but what is your opinion on mobile cell signal boosters such as 3G, 4G, and specifically LTE. I have the Wilson Electronics signal booster
http://www.wilsonelectronics.com/store/ ... sleek-4g-a, this Laird antenna http://www.wpsantennas.com/TRA6927M3NB- ... tenna.aspx, and this multi-band antenna, though not many specs on it http://www.antennagear.net/servlet/the- ... and/Detail.

The mount is a permanent NMO 3/4" on my 2010 Toyota Tacoma center of roof. From the booster cradle to the mount is low-loss cable.

Thoughts and opinions?

[nukedude]

I have used UHF Antennex Phantom antennas on a car and SUV since 2004. They have held up well but have faded from the original black to a dull gray color. At one point I also had the "soup can" looking VHF mounted until I realized how narrow it was in bandwidth. It was replaced with a 1/4 wave whip.

Where I work, these antennas were used on RHIB, rigid hull inflatable boats, that did not have much space to place a long whip antenna. These were 4 man RHIB's. A metal plate was added to the fiberglass console as a ground plane in order for them to work properly. They didn't work too well as the ground plane needed to be bigger.

They tend to work well in the center of the roof or center of trunks on cars due to a larger ground plane.

[Birken Vogt]

The Laird Phantom seems to work pretty good. We have found that a 1/4 wave seems to work the best for cell. The fancy ones such as the 8 dB that you linked just do not seem to have as good of performance as a simple 1/4. Must be something to do with sharpness or nulls in the pattern. The Phantom is slightly shorter than 1/4 wave so I don't know what kind of magic it has inside.

I know the thread is old, but what is your opinion on mobile cell signal boosters such as 3G, 4G, and specifically LTE. I have the Wilson Electronics signal booster
http://www.wilsonelectronics.com/store/ ... sleek-4g-a, this Laird antenna http://www.wpsantennas.com/TRA6927M3NB- ... tenna.aspx, and this multi-band antenna, though not many specs on it http://www.antennagear.net/servlet/the- ... and/Detail.

The mount is a permanent NMO 3/4" on my 2010 Toyota Tacoma center of roof. From the booster cradle to the mount is low-loss cable.

Thoughts and opinions?

[motorola_otaku]

The FD I work for used to run Phantom Elites for UHF until we started sweeping them with an analyzer during a mobile cut-over project. Almost all of them -I'd say 80-85%- installed on AEV ambulances, Pierce fire cabs, and Ford Expeditions and F-series pickups had a nice dip at 446 MHz but would sharply sweep up to 2.0-3.0 SWR above 461 MHz. We swapped them all out with 1/4-wave stingers and on all but a handful of vehicles we observed >1.5 SWR from 440 to 480 MHz.

[k4iii]

I've noticed water gets into the phantom elites with the leading edges over time. However, usually the round puck or shotglass phantoms are more robust to moisture intrusion... Moisture causes issues based on the type of nmo mount and corrosion between the center contact and ground components. Of course i'm also in FL with bad humidity! Cleaning can cure a bad vswr, if the water is not doing permanent damage or rust around inside around the nmo mount... The round shotglass type on 450 and 800 has circular polarization so if the transmitted signal bounces off buildings and trees like in a city or forest, using the round phantoms have much less "flutter" while in motion than a vertical whip. I've found that a 3dB meg gain on circular antenna is about unity gain with a whip, except while in motion, the signals both transmit and receive have less flutter. I wouldn't see a use for base to base or fixed station use... only when a mobile user is in congested terrain. For desert or wide open areas, I'd stick to a whip... If you travel through forested roadways or cities I notice quite a reduction on picket fencing or flutter noise! Longevity and durability go with whip, plastic fades gets brittle over time... You have to justify this product...