Antenna Problem

[WSGI548]

So trying to sort out an antenna problem…

I have a Nagoya UT72G which I have been using as a home antenna on a paint pole with a pizza pan and it worked great. Using a UV5G Plus I was routinely hitting a repeater 49 miles away on medium or high, no problem. So recently improved the home antenna and recycled the UT72G to the car, 2016 Kia Soul. Nice spot, center of the roof, cable all nicely routed with no pinching or severe bending…. And it doesn’t work worth crap. I can literally stand in my Driveway and hit the 40 mile distant repeater, scratchy but readable, with my HT by itself. Same HT hooked to antenna on car, won’t even trip the repeater. Everything looks fine on a meter, and as I said, same antenna and handheld being used in same location with no problem. I can even barely receive anything while moving or parked, and car on or off.

Anybody have any ideas why?

I know it is an inexpensive antenna, but it has been working great, until I try to use it on the car. Any guidance on this is welcome.

[OffRoaderX]

Double check that the antenna is screwed-in/connected correctly and fully - assuming you mean no shorts or high SWR when checking on your meter I'm not sure what else to recommend.

I would point out that of all the mobile antennas I have tested (probably about 20), the UT72G was the worst performing of all of them - performing worse than even the little ghost-antenna's I have tested.. So if you have to replace it, dont feel bad and be secure in knowing that whatever you replace it with will perform better (unless you replace it with another UT72G).

[SteveShannon]

32 minutes ago, WSGI548 said:

So trying to sort out an antenna problem…

I have a Nagoya UT72G which I have been using as a home antenna on a paint pole with a pizza pan and it worked great. Using a UV5G Plus I was routinely hitting a repeater 49 miles away on medium or high, no problem. So recently improved the home antenna and recycled the UT72G to the car, 2016 Kia Soul. Nice spot, center of the roof, cable all nicely routed with no pinching or severe bending…. And it doesn’t work worth crap. I can literally stand in my Driveway and hit the 40 mile distant repeater, scratchy but readable, with my HT by itself. Same HT hooked to antenna on car, won’t even trip the repeater. Everything looks fine on a meter, and as I said, same antenna and handheld being used in same location with no problem. I can even barely receive anything while moving or parked, and car on or off.

Anybody have any ideas why?

I know it is an inexpensive antenna, but it has been working great, until I try to use it on the car. Any guidance on this is welcome.

What do you mean by “Everything looks fine on a meter?”  What kind of meter?  

As a sanity check, go back to your original configuration and see if it still works. 

[LeoG]

You have a 5 watt HT connected to it's antenna and you can hit the repeater from your driveway.  But when you use an adapter to connect your HT to the antenna system on the car you are introducing a good deal of loss through the adapter and the thin RG-58A/U that comes with the UT72.  The antenna itself says it's 3.5dBi which is 1.35dBd, which isn't very much.  Loss of 13' of cable is .85dB which leaves you with a .5dB gain.  Not enough to make up for cable losses.

[OffRoaderX]

27 minutes ago, WSGI548 said:

Are there any recommended replacements?

You're going to get a lot of opinions basically re-affirming what everyone purchased themselves as "the best".. As mentioned previously I have tested pretty much every GMRS antenna on the market and literally, with the exception of the UT-72G, they all work pretty much the same (ie; your human ear will not notice any difference, nor will the human ear of the guy listening to you)...  
MY favorite, that i use on both of my Jeeps as well as on a cookie-sheet in the window of my office is the Midland MXTA26 - it performs the same as any other but because it has the twist/coil in the center its a couple of inches shorter than most.

If you want REALLY short, and ONLY IF you are able to mount it top-center of your vehicle, then the Midland (and other brand) Ghost type antennas work very well .. not quite as well as their larger brethren, but noticeably better than the UT-72G based on my testing.  WARNING: "Some people" will proclaim that the ghost antennas "do not work" and are "just a dummy load".  These proclamations, based on my data from actual testing, rather than based on opinions, low self-esteem and biases, are 100% stupidity-based fallacies and anyone making these proclamations should to pointed-to, laughed at, and ignored.

[WRUE951]

are you pulling your Kia out of the garage before you try taking?    

[WRYZ926]

12 minutes ago, WRUE951 said:

are you pulling your Kia out of the garage before you try taking?    

That will definitely make a difference, especially if it is a low ceiling and the metal garage door frame and tracks can and will have an effect.

[WSGI548]

1 hour ago, WRUE951 said:

are you pulling your Kia out of the garage before you try taking?    

Yes.

I tried taking an antenna selfie while driving, but it is not as easy as it looks.

[OffRoaderX]

19 minutes ago, LeoG said:

But when you use an adapter to connect your HT to the antenna system on the car you are introducing a good deal of loss through the adapter and the thin RG-58A/U that comes with the UT72.  The antenna itself says it's 3.5dBi which is 1.35dBd, which isn't very much.  Loss of 13' of cable is .85dB which leaves you with a .5dB gain.

Very good point that I missed - and the cable on the UT72G is, as many "experts" here like to say "junk".. very cheap/low quality.. not to mention the adaptor in use could be junk/bad.

[WSGI548]

2 hours ago, SteveShannon said:

What do you mean by “Everything looks fine on a meter?”  What kind of meter?  

As a sanity check, go back to your original configuration and see if it still works. 

An SW102 to verify the SWR. I will try throwing it back up tomorrow if the wind dies down.

 

1 hour ago, OffRoaderX said:

Double check that the antenna is screwed-in/connected correctly and fully - assuming you mean no shorts or high SWR when checking on your meter I'm not sure what else to recommend.

I would point out that of all the mobile antennas I have tested (probably about 20), the UT72G was the worst performing of all of them - performing worse than even the little ghost-antenna's I have tested.. So if you have to replace it, dont feel bad and be secure in knowing that whatever you replace it with will perform better (unless you replace it with another UT72G).

I kinda figured I would end up having to replace it. I will start looking for something a little nicer, just figured I could recycle this one.

 

19 minutes ago, LeoG said:

You have a 5 watt HT connected to it's antenna and you can hit the repeater from your driveway.  But when you use an adapter to connect your HT to the antenna system on the car you are introducing a good deal of loss through the adapter and the thin RG-58A/U that comes with the UT72.  The antenna itself says it's 3.5dBi which is 1.35dBd, which isn't very much.  Loss of 13' of cable is .85dB which leaves you with a .5dB gain.  Not enough to make up for cable losses.

The only adapter is a SO259 to BNC which is what I have been using at my house with it as base antenna.

 

If the wind dies down I will throw it back up on the pizza pan & pole and verify it is still working fine. It is no biggie to replace as it was inexpensive. I am just surprised it was working as a “base” antenna, but won’t work on the car. 

[WSGI548]

I guess I should have also asked… Are there any recommended replacements?

I would like to stick with something preferably about the same size or not too much bigger, smaller would work as well. 

[WSGI548]

4 hours ago, SteveShannon said:

What do you mean by “Everything looks fine on a meter?”  What kind of meter?  

As a sanity check, go back to your original configuration and see if it still works. 

Steve,

Wind is still up a bit, but I took it off the car and threw it on a pizza pan on a 6’ shelf in the garage(only about a 1’ taller than car and 4’ away). Hit the repeater a little unreadable, but got a response to a radio check. Threw it back on the car with all the coax outside the car, nothing. Then threw it on top of a water heater, got a squelch tail from the repeater. Either that extra foot is all the difference, or my car is a radio blackhole. I think I am gonna read up on Kia Souls and ham radio and see if there have been any issues. Thanks everyone for the help. If I find the issue, or a fix for the issue, I will report back.

[SteveShannon]

18 minutes ago, WSGI548 said:

Steve,

Wind is still up a bit, but I took it off the car and threw it on a pizza pan on a 6’ shelf in the garage(only about a 1’ taller than car and 4’ away). Hit the repeater a little unreadable, but got a response to a radio check. Threw it back on the car with all the coax outside the car, nothing. Then threw it on top of a water heater, got a squelch tail from the repeater. Either that extra foot is all the difference, or my car is a radio blackhole. I think I am gonna read up on Kia Souls and ham radio and see if there have been any issues. Thanks everyone for the help. If I find the issue, or a fix for the issue, I will report back.

Move the car and try again. 

[LeoG]

2 minutes ago, SteveShannon said:

Move the car and try again. 

Yup, sometime inches can make a difference let alone feet.

[WSGI548]

1 hour ago, SteveShannon said:

Move the car and try again. 

I moved the car, but no difference. So it got me thinking and I moved the antenna around the car. Guess what… different places on the roof, no difference. Hatch top, no difference. Even tried doors and fenders, no difference. But finally, smack dab in the middle of the hood, bam, keyed the repeater with a radio check and got a response. Doesn’t make sense to me, but it worked. Maybe the type of body metal?  

I am gonna play around with it some more tomorrow, to see if I can figure out if the metals are different.

[SteveShannon]

7 hours ago, WSGI548 said:

I moved the car, but no difference. So it got me thinking and I moved the antenna around the car. Guess what… different places on the roof, no difference. Hatch top, no difference. Even tried doors and fenders, no difference. But finally, smack dab in the middle of the hood, bam, keyed the repeater with a radio check and got a response. Doesn’t make sense to me, but it worked. Maybe the type of body metal?  

I am gonna play around with it some more tomorrow, to see if I can figure out if the metals are different.

Good job trying different things.  It doesn’t make sense to me either, but based on past experiences that definitely means little.  Did you feel any difference in how well the magnet holds for these different locations? The magnetic base couples with the metal to form the ground plane. It would be interesting to see if a non-ground plane antenna worked better in your specific circumstances.

Also, play around with your cable.  You might have a problem that manifests itself when some portion of the cable is bent or straightened but not others. That could form an intermittent problem that coincidentally happens as you move the base around.

Radio is sometimes the most frustrating mystery, but I have found that most problems have simple solutions, propagation being the exception. 

[nokones]

12 hours ago, WSGI548 said:

An SW102 to verify the SWR. I will try throwing it back up tomorrow if the wind dies down.

 

I kinda figured I would end up having to replace it. I will start looking for something a little nicer, just figured I could recycle this one.

 

The only adapter is a SO259 to BNC which is what I have been using at my house with it as base antenna.

 

If the wind dies down I will throw it back up on the pizza pan & pole and verify it is still working fine. It is no biggie to replace as it was inexpensive. I am just surprised it was working as a “base” antenna, but won’t work on the car. 

 

What readings does the meter show for VSWR and reflected power on both the 462 & 467 Meg channels with the portable radio connected to the antenna on the car?

That antenna is a dual band antenna and will not provide optimum service on either band. It is a compromise to be mediocre on both bands. I bet an antenna analyzer would reflect and substantiate those facts.

As the Queen stated, the best out of the box GMRS antenna is the Midland MXTA 26. You'll be surprised with the VSWR meter that antenna produces for GMRS freqs.

[TrikeRadio]

14 hours ago, WSGI548 said:

I moved the car, but no difference. So it got me thinking and I moved the antenna around the car. Guess what… different places on the roof, no difference. Hatch top, no difference. Even tried doors and fenders, no difference. But finally, smack dab in the middle of the hood, bam, keyed the repeater with a radio check and got a response. Doesn’t make sense to me, but it worked. Maybe the type of body metal?  

I am gonna play around with it some more tomorrow, to see if I can figure out if the metals are different.

Here is a funny idea... put that pie pan you were using between the car roof and the antenna and see what you get. Seems like that roof of your car is not working as the ground plane .. but your hood is.

[Socalgmrs]

Some times stuff happens when you move antennas.   I’d just toss it and get a new one for the car.