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Smiley Antenna Slim Duck GMRS 465MHz 5/8 Wave.??


WSAA635

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I agree with SShannon that terrain is the main factor.

This said, I have the 771G Nagoya antennas on a couple handhelds and it’s shorter siblings on a couple others. I also have the Smiley Slim Duck on two and generally find it performs better than the stock antenna or shorter Nagoya, but about the same as the 771G. I prefer the Smiley.

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I hate to burst y'all's bubble, but the longer antenna on an HT won't help. That 771G Nagoya is a 5/8 wavelength antenna, which in order to have "gain" in the plane normal to the antenna would require a ground plane diameter of at least 1 wavelength. Obviously the radio is not that. What you really want is a simple 1/4 wavelength antenna (about 6 inches at GMRS) that has LOW LOSS, meaning it's efficient. With the GMRS HTs being also about 6 inches tall this makes for a really nice dipole antenna. A simple piece of heavy gauge copper wire would work just fine, but would not be so good mechanically. And that would not be so good for VHF, only tuned to UHF. 

I took a chance on this antenna and found it to be excellent since it's just a copper wire encased in flexible plastic. https://www.amazon.com/gp/product/B0855PVDWS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You will find that Motorola uses this concept on their HT's and for a good reason: it works the best for a handheld. 

The bottom line: for a handheld radio, you want radiation efficiency. Any antenna that has fancy coils to tune them is by definition low efficiency. Radiation pattern make little to no difference, and radiation pattern is the only thing you get with an antenna system longer than 1/2 wave dipole. Consider that over a propagation path you have no idea what the best path is to the other station at any point in time. Consider an urban or forest environment: reflections off of a building, car, tree is frequently the best path, and that changes literally by the foot as you walk around. 

Hope this helps. 

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2 hours ago, WRUW493 said:

 

I hate to burst y'all's bubble, but the longer antenna on an HT won't help.

 

Actual measurements of signal strength performed by swapping between the OEM antenna on my UHF radio and a clone of the Nagoya (Tid Radio 771) dispute that. 
Sitting at my kitchen table I transmitted to a DMR repeater 16 miles away. I watched the signal reports using a Brandmeister connected dashboard. 
When I transmitted using the factory rubber duck the signal strength was reported as s6.

Then I removed the factory antenna and replaced it with the clone 771 antenna. The signal varied between s7 and s8. 
Going back to the original antenna the signal strength went back down. 
 

Those are reproducible data. 
Since then I have replaced the original antennas on two of my best radios with Diamond 771 antennas. I consistently get good signal reports from other hams on both 2 meters and 70 cm when using these antennas.

As an aside, I don’t know what the number 771 indicates.

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On my BTech GMRS V2's I've been using the ABBREE 771C with is a GMRS antenna that's a nice orange color, LOL. They seem to work well enough. For the new KG-UV9D Plus I ordered a Nagoya 771G since it's a nice radio and deserves a nice antenna.

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Hi Shannon,

Thanks for the really good info and testing. Real world testing is always helpful. 

I see that the 771 antenna is 15.5 inches long, making it about 5/8 wavelength. The radiation pattern of a 5/8 wavelength with very little ground plane (the HT) is a rather high angle of radiation, probably 45 degrees or so. I don't know what the OEM antenna was. 

Couple of things to consider:

1- Since antennas do not create power, they only direct more in one direction than another direction. So without performing a similar experiment with the HT is quite a few orientations it's hard to say how the 771 (or any antenna for that matter) will behave in a variety of RF environments. This is why antennas are measured in RF anechoic chambers in dozens of orientations and then averaged together for a final evaluation. I have taken real world RF propagation data from a handheld (cell phone) to base station where not only does the best RF path change direction by 10's of degrees with every fraction of a foot change in location, but also inside of buildings with multiple reflections taking place it's not uncommon for the best RF path to be a TX polarization different or even orthogonal polarization to the RX antenna. 

2- It's real easy to have poor radiation efficiency on dual band antennas. Loading coils and dual band related compromises all are opportunities for loss, read RF absorption. It could be as simple as the OEM antenna has poorer efficiency than the 771. This too would show up in a test of multiple orientations in a controlled environment. 

These are why that in the general case one wants a mostly spherical radiation pattern (read low "gain") and high efficiency. Then one has the best chance overall of having good radiation in the direction that the repeater/other mobile appears to be from the HT's perspective. 

Hope this helps, and keep up the good work :)

 

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12 hours ago, WRUW493 said:

Hi Shannon,

Thanks for the really good info and testing. Real world testing is always helpful. 

I see that the 771 antenna is 15.5 inches long, making it about 5/8 wavelength. The radiation pattern of a 5/8 wavelength with very little ground plane (the HT) is a rather high angle of radiation, probably 45 degrees or so. I don't know what the OEM antenna was. 

Couple of things to consider:

1- Since antennas do not create power, they only direct more in one direction than another direction. So without performing a similar experiment with the HT is quite a few orientations it's hard to say how the 771 (or any antenna for that matter) will behave in a variety of RF environments. This is why antennas are measured in RF anechoic chambers in dozens of orientations and then averaged together for a final evaluation. I have taken real world RF propagation data from a handheld (cell phone) to base station where not only does the best RF path change direction by 10's of degrees with every fraction of a foot change in location, but also inside of buildings with multiple reflections taking place it's not uncommon for the best RF path to be a TX polarization different or even orthogonal polarization to the RX antenna. 

2- It's real easy to have poor radiation efficiency on dual band antennas. Loading coils and dual band related compromises all are opportunities for loss, read RF absorption. It could be as simple as the OEM antenna has poorer efficiency than the 771. This too would show up in a test of multiple orientations in a controlled environment. 

These are why that in the general case one wants a mostly spherical radiation pattern (read low "gain") and high efficiency. Then one has the best chance overall of having good radiation in the direction that the repeater/other mobile appears to be from the HT's perspective. 

Hope this helps, and keep up the good work :)

 

I agree that antennas don’t create power and I understand gain. 
I use my radios with the antenna vertical. For me, having a spherical pattern, like an isentropic antenna, would be wasteful because I don’t typically communicate with something directly above or below me. But I understand your point that having a high gain antenna with the radiation directed in the wrong direction can be even worse.  I also agree that a low efficiency antenna is a bad thing. Unfortunately most of us (definitely me) don’t have an easy way to assess efficiency. Real world testing like I conducted are the best I can do. 
 

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My stock antennas on all my hand helds fell off at about 10-12miles. Some much less.  My 771 antennas easily reach out over 20miles to one repeater and over 30to another repeater so I’d say the 771 just works better.   Some one else can do all the sciency stuff and tell me how they don’t work but I know they work much better than any other I’ve tried for my hand helds.  

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  • WSAA635 changed the title to Smiley Antenna Slim Duck GMRS 465MHz 5/8 Wave.??
  • 2 weeks later...

Update. Don't waste your money. I had one on my UVD1P and couldn't talk to a buddy that was only 3/4 of a mile away. The factory Wouxun antenna that came with the radio on the Baofeng UV-82 would reach him no problem and when I put the factory antenna back on the UVD1P I could reach him too so the Smiley Duck isn't worth it IMHO.

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  • 2 weeks later...
On 1/20/2024 at 7:56 PM, WRUW493 said:

I hate to burst y'all's bubble, but the longer antenna on an HT won't help. That 771G Nagoya is a 5/8 wavelength antenna, which in order to have "gain" in the plane normal to the antenna would require a ground plane diameter of at least 1 wavelength. Obviously the radio is not that. What you really want is a simple 1/4 wavelength antenna (about 6 inches at GMRS) that has LOW LOSS, meaning it's efficient. With the GMRS HTs being also about 6 inches tall this makes for a really nice dipole antenna. A simple piece of heavy gauge copper wire would work just fine, but would not be so good mechanically. And that would not be so good for VHF, only tuned to UHF. 

I took a chance on this antenna and found it to be excellent since it's just a copper wire encased in flexible plastic. https://www.amazon.com/gp/product/B0855PVDWS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You will find that Motorola uses this concept on their HT's and for a good reason: it works the best for a handheld. 

The bottom line: for a handheld radio, you want radiation efficiency. Any antenna that has fancy coils to tune them is by definition low efficiency. Radiation pattern make little to no difference, and radiation pattern is the only thing you get with an antenna system longer than 1/2 wave dipole. Consider that over a propagation path you have no idea what the best path is to the other station at any point in time. Consider an urban or forest environment: reflections off of a building, car, tree is frequently the best path, and that changes literally by the foot as you walk around. 

Hope this helps. 

Thanks for this.. Makes perfect sense. Simplicity, balance, and efficiency.. 

Have you ever messed around with pig tail counterpoising for HT antennas? If it works, I wonder why manufacturers haven’t incorporated it as a standard design..

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Also, the good news is that it’s GMRS that we’re discussing here. No need to “dual band” anything.. We should enjoy the luxury of only needing to target one resonant frequency “chunk” and making the best of it…

For 462-467 the quarter wave, purpose cut for that specific frequency (shorter) would provide a better balanced dipole to the radio body…

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