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Posted

Since NOONE is bothering to look, the 2 items are ground plane brackets, that I don't believe I even need, other than to attach a cable at one end and antenna on the other. I asked the question before I wasted anymore money on the Nagoya if the result will be the same, I needed a bracket, similar to the Midland MXTA-23 I believe only without a cable attached to mount the antenna more securely to the top of the 25' flagpole I put it on top of.

 

Having gotten my answer with that, I do still have questions as to why I'm still getting the problem as far as the links, most forums will convert links to photos and since there's so many sad hams here I quit coming here for answers and generally look elsewhere. Not able to find what I was looking for for, I posted in the most logical place to ask my question. Other forums will convert posts to visual of items and even those that don't, most people actually at least click on one to know what they're talking about before even posting comments back. Then sad hams aren't part of those forums either 

Posted
46 minutes ago, CyborgAlienWRYG738 said:

I knew who he was talking to. I also know that something's awry with the 4.6 SWR readings. I'm running a tuned Laird B4505CN on top of it. Tuned using a Laird G8 base. I expected it to be off, I didn't expect it to be off that much.

To what do you have the antenna mounted?

Posted
36 minutes ago, CyborgAlienWRYG738 said:

Since NOONE is bothering to look, the 2 items are ground plane brackets, that I don't believe I even need, other than to attach a cable at one end and antenna on the other. I asked the question before I wasted anymore money on the Nagoya if the result will be the same, I needed a bracket, similar to the Midland MXTA-23 I believe only without a cable attached to mount the antenna more securely to the top of the 25' flagpole I put it on top of.

 

Having gotten my answer with that, I do still have questions as to why I'm still getting the problem as far as the links, most forums will convert links to photos and since there's so many sad hams here I quit coming here for answers and generally look elsewhere. Not able to find what I was looking for for, I posted in the most logical place to ask my question. Other forums will convert posts to visual of items and even those that don't, most people actually at least click on one to know what they're talking about before even posting comments back. Then sad hams aren't part of those forums either 

I literally clicked on both link and looked at them. That's how I knew what they looked like. You asked, acontextually, which one was best. You gave no context. And then you started insulting the people and software they are running who are trying to help you. 🤷‍♂️

Posted
1 hour ago, Northcutt114 said:

didn't notice that the Nagoya was tri-band. So aluminum is better for tri-band than brass? Why would that be?

My point is the two different lengths of the poles make for 3 differently tuned ground planes.

I paid no attention to the frequencies the plane offered; it was not easily available.

One length is one band, the other a second and combined you end up with the cheaper 20" 'UHF' option.

The cheaper one will work but you have no ability to trim/tune it on the plane.

That is assuming Nagoya has the assembly for each band somewhere. You can guess around 8" is GMRS if nowhere else to start and try the other one for best SWR.

I doubt 20" is optimal for any GMRS antenna.

 

There are reasons, I'm not getting into, why this is not as much an issue on a car but I will add moving the magnet around is enough to 'tune' the plane on a mostly-flat metallic surface >8".

Edit-

For some reason I referred to the other one as cheaper when it is $10.00 more.

Does not change my 'opinion'.

Posted

Images of what I have, the Browning LMR-400 cables are a 25' run down the inside of the pole to a lightening arrestor in the ground attached to a 50' to the Radio. Currently, I have the Midland MXTA-26 antenna on it, trying to see if any difference in SWRs, maybe .1-.3 difference.

IMG_20250816_175947739_AE.jpg

IMG_20250816_175921575_AE.jpg

Posted
5 hours ago, CyborgAlienWRYG738 said:

I got the Tram one, when all was assembled, it's getting 4.6+ SWR, I was curious if it was maybe it being defective or  what's the possible cause of the problem, reason for my initial query.

I'm sorry: the thread went off the rails and i missed this information.

It's, probably, too large.

 

You can try sticking in rods that fit, they can even droop a bit, and try shorter lengths.

Seriously:

If you can cut a coat hanger and if it will fit, not strip threads and not droop much, the field will not know.

It wont last but you can experiment.

Posted
2 hours ago, CyborgAlienWRYG738 said:

I knew who he was talking to. I also know that something's awry with the 4.6 SWR readings. I'm running a tuned Laird B4505CN on top of it. Tuned using a Laird G8 base. I expected it to be off, I didn't expect it to be off that much.

At what frequency is that 4.6:1 SWR?

Do you have an antenna analyzer that will sweep the range from 462 to 468 MHz so you can see where the minimum SWR ratio occurs?  Maybe the antenna just needs tuning. 

Posted
15 hours ago, SteveShannon said:

At what frequency is that 4.6:1 SWR?

This not trivial:

The SWR should be checked in the middle of the band or sweep 462.0-480.0; it's just wide enough to see the peripheral readings.

 

When trimming the antenna, and it no longer goes down, start trying different length rods. If you have aluminum tape, you can make a round ground plane, ~10" from the center, cut a hole and slide it in position then, using a compass or similar device, shave down until the SWR stops dropping and starts going up. That is the diameter you need; cut rods accordingly.

The physics is different for a solid plane opposed to a waveform-rod plane but it is a cheap way to test. Cut a circle out of cardboard, cut a center hole that will collar tightly and then tape it with the aluminum. Gaps look sloppy but the wavelength is too large for them to matter (e.g. rods). When you tape over the center hole, cut a cross and fold over. This makes the electrical contact. Just snug is enough but tilting won't work.

You have asked about metals. Don't worry about that. Mixing metals can cause corrosion (chemistry, not 'antenna' specific) over time but will not affect your tuning. Antennas form photons in at the quantum level, they don't 'glow' like most things that make 'light'. It forms a near field and that pops off photons.

At our level, different metals are just accounted for with trimming/tuning. 

If you can die the rods with threads, you may feel 'safer' but drooping rods is actually a contested discussion; I'm surprised someone has not posted a troll about drooping being desired. 

About the 'plane' not caring about the metal

If you make rods that work, thread and are weather resistant, you can keep using them and have no need to butcher the rods that shipped. The tips are unnecessary; they are to mitigate eye pokes.

Finally:

1004SWRa.thumb.gif.e09188daa26f4d42f8b31d0bdc0055bf.gif .

 

This Frankenstein's monster gets a 1.004 SWR across the entire GMRS band (according to my Nanova-H).

Paper plate, 7mm 25lb magnet under the can, to pull the antenna firmly to the aluminum tape. It's dual-band for aircraft but I don't Tx on that band.

I cut one down 4 times and that was the size that worked best. 

Just to demonstrate 'perfect' is relative.

The antennas are perfectly tuned out of the bag so I knew my high SWR was my ground plane. 

Posted
16 hours ago, SteveShannon said:

At what frequency is that 4.6:1 SWR?

Do you have an antenna analyzer that will sweep the range from 462 to 468 MHz so you can see where the minimum SWR ratio occurs?  Maybe the antenna just needs tuning. 

No I don't have one just my Surecom SW-102. I'm trying to afford things as I can right now. Thanks for the help. I'm to the point I could use some physical help but, I don't know anyone nearby who has time for it or wants to travel this far, even if I pay them.

Posted
1 minute ago, CyborgAlienWRYG738 said:

Yeah I checked the entire band it's only a few decimal points between channel 1 and 32. 

Okay. With 5 MHz between the 462 MHz channels the the 467 MHz channels there’s usually some swings high or low that will appear on an analyzer in the off channel frequencies (463-466) or higher and lower than the GMRS channels. There should be a dip somewhere along the spectrum. 
 

Also, instead of the ground plane devices you asked about, a lot of people simply attach the antenna mount to a big cookie sheet. You could try that. It’s especially easy to try if you have a magnetic mount and a steel cookie sheet or pie plate. 

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