AirNav VHF Airband 118-136 MHz Outdoor Antenna with SMA Connector?

[iMONITOR]

I'm always looking for airband antennas, but VHF & UHF. I ran across this one from AirNav that I was completely unaware of. I was about to build one myself buy why reinvent the wheel? Does anyone own one or tried it? I'm posting it here in the Aircraft Monitoring Forum instead of the Antenna Forum due to being airband specific. Mods feel free to move if necessary. I'd appreciate your comments. Below are the specs:



Omni-directional Antenna optimized for long and short range VHF Airband reception (118-136 MHz). Shipped with a 7.5 meter cable and SMA connector. Compatible with any VHF Airband receiver and with other suitable SMA connector receivers.
FEATURES

Outdoor Vertical External 118-136 MHz Antenna.
Gain 5dBi, Vertical Polarization.
Built with fiberglass & aluminum alloy. For both indoor & outdoor use.
Guaranteed range improvement. Tested in extreme weather conditions.
Mounting bracket and 7.5-meter cable included.


AirNav VHF Airband 118-136 MHz Outdoor Antenna with SMA Connector

AirNav VHF Airband 118-136 MHz Outdoor Antenna with SMA Connector

DESCRIPTION Omni-directional Antenna optimized for long and short range VHF Airband reception (118-136 MHz). Shipped with a 7.5 meter cable and SMA connector. Compatible with any VHF Airband receiver and with other suitable SMA connector receivers. FEATURES Outdoor Vertical External 118-136 MHz...

radarbox24.myshopify.com

Also available from Amazon

Amazon.com

 

[nd5y]

There is no way an antenna that small can have 5 dBi gain at 118-136 MHz.

 

[ko6jw_2]

You should consider a discone. It will have flat response on both VHF and UHF bands. Gain in antenna is achieved by lowering the radiation angle. That may be fine for two way radio where the units are on the ground. Aircraft are not. Although discones have unity gain they have higher radiation angles which could benefit air band reception. Aircraft radios use lower power because they are primarily line of sight.

An isotopic antenna is a theoretical construct. There is no such thing in the real world. A ground plane has about 2.5dBi gain. This antenna seems to be a quarter wave long but with no ground plane. I wouldn't buy it.

 

[mass-man]

Try this....it is used by the FBO at my local airport...been up there for years, and they have no complaints about its performance.

Sirio GPA 108-136 Mhz Air band ground plane base antenna [gpa108136] - $65.00 : Sirio Antenna, High Performance Antenna Made in Italy

Sirio Antenna Sirio GPA 108-136 Mhz Air band ground plane base antenna [gpa108136] - Sirio GPA 108-136 is 1/4 λ VHF base antenna for professional and HAM 4m bands 108-136MHz. Manufactured from robust aluminim alloy and weather proof plastics. High quality materials garrantee maximum...

www.sirio.store

 

[prcguy]

Ha! Funny story about the Sirio air band antenna and the OP but I'm not telling.

Try this....it is used by the FBO at my local airport...been up there for years, and they have no complaints about its performance.

Sirio GPA 108-136 Mhz Air band ground plane base antenna [gpa108136] - $65.00 : Sirio Antenna, High Performance Antenna Made in Italy

Sirio Antenna Sirio GPA 108-136 Mhz Air band ground plane base antenna [gpa108136] - Sirio GPA 108-136 is 1/4 λ VHF base antenna for professional and HAM 4m bands 108-136MHz. Manufactured from robust aluminim alloy and weather proof plastics. High quality materials garrantee maximum...

www.sirio.store

 

[mass-man]

Ah the back story...I only recommend it cuz I put it up 5 years ago for the FBO and yearly check it for rust or whatnot and it's still bright and shiny!

 

[Dog]

I built one of these for mil air. Homebrewed Off-Center Fed Dipole except half that size, 24" and 9"

 

[dave3825]

I built one of these for mil air. Homebrewed Off-Center Fed Dipole except half that size, 24" and 9"

What was the freq range for the 48 & 18 version. I made one years ago but do not remember and do not see anything about operating range on the wiki page.

How did the half version work for you?

 

[Dog]

What was the freq range for the 48 & 18 version. I made one years ago but do not remember and do not see anything about operating range on the wiki page.

How did the half version work for you?

I built mine years ago, I don't remember and couldn't find the page that I got the information from last night. A couple of things I remember was the larger profile. (copper pipe vs say wire) was more wide banded. I made mine out of 1/2 copper pipe. I did mine at half for space restrictions. It isn't in an ideal spot. It works well for my purposes. There are calculators online to figure out all the tech stuff for off center dipoles.

 

[Edelweiss]

Agree, no chance of the gain figures being realistic. SMA connector is awful for outdoor use and not nice for large dia cable. Stick with the Sirio, it's doing the job fine for me as well and they don't lie about the data. It's essentially a pro-antenna at a very affordable price.
Mike

 

[GlobalNorth]

It is an indoor antenna designed to placate spouses and HOA spies. If you are limited to an indoor antenna and can't put up anything in the attic because of solar panel arrays or physical limitations, it's about the best choice.

 

[billpritjr]

You can buy any 2-meter Ham antenna and use it for receive on Aviation band, it will work great.

 

[prcguy]

You can buy any 2-meter Ham antenna and use it for receive on Aviation band, it will work great.

I've measured many 2m ham antennas on VHF air for signal strength and most do not work very well. They can be 10dB or more down, especially at the bottom of the VHF air band. I have a number of actual VHF airport antennas to compare with.

 

[billpritjr]

I've measured many 2m ham antennas on VHF air for signal strength and most do not work very well. They can be 10dB or more down, especially at the bottom of the VHF air band. I have a number of actual VHF airport antennas to compare with.

thanks. Used them for 30 years with zero issues.

 

[alcahuete]

thanks. Used them for 30 years with zero issues.

Thirty years with zero issues is different than 30 years with an underperforming antenna. No way, no how will a 2m antenna outperform an antenna designed for the airband. The physics won't let it happen.

 

[prcguy]

Thirty years with zero issues is different than 30 years with an underperforming antenna. No way, no how will a 2m antenna outperform an antenna designed for the airband. The physics won't let it happen.

This is one of those things were you don't know until you know. Put up a full aircraft band rated ground plane, Discone or sleeve dipole as used at most airports, measure distant ATIS levels then replace with a ham band antenna on the exact same mount, same height. Results will be surprising and probably disappointing.

 

[majoco]

I'll leave you to do the sums for 125MHz but this looks quite good. I made a sleeve dipole many years ago for 70cm band and if I remember correctly it worked quite well. I used a larger piece of plastic pipe with caps each end to cover the choke and extend below long enough to use hose clips to fix it to an aluminium mast.

Build a Sleeve Dipole Antenna for 2m VHF - DW1ZWS - Philippines

Build a 2m VHF lightweight sleeve dipole antenna. A compact portable antenna and easy for deployment. You can even operate the dipole holding it.

dw1zws.com

 

[PDXh0b0]

I built one of these for mil air. Homebrewed Off-Center Fed Dipole except half that size, 24" and 9"

Build this one back in 2020, 30 feet in the air, worked great

 

[Edelweiss]

I would agree, a 2 m antenna normally has a very sharp resonance is not the best choice for airband. It will work but you're better off with something else, at least tune it to a lower resonance frequency. M (antennas are covered in quite some detail in my book

 

[prcguy]

Build this one back in 2020, 30 feet in the air, worked great

Did you compare it to another antenna to determine its great?