KG-905G Disappointing Short Distance Test

[fillmoreranger]

Hi…

I am new to GMRS. I recently purchased two Wouxun KG-905G HT radios (buytwowayradios.com), replacing the stock antennas with the Nagoya NA-771G. I reside in a suburban subdivision. For my initial test (running 5w on Ch 5), I took one radio to a 3rd floor unit in a building 0.9 miles away, per Google Maps (a bit shorter as the crow flies). I expected a clear signal at that distance, but was not the case. My TX’s were not received by the 3rd floor unit. Their TX’s were hit or miss. Some came through (with static), others did not.

The only impediment I can really think of is a line of those massive overhead electrical power lines that cut across the two locations. 

Would that be enough to knock out a signal between these relatively short distance locations? Any suggestions to improve communications?

Obviously, a disappointment starting out.

Thanks in advance.

 

[radiozip]

Won't be power lines limiting a UHF signal, more so something solid. Any hills between these locations? That will definitely limit coverage.

[OffRoaderX]

Can you SEE the building you are trying to reach? if not, something is blocking the signal.. How many, and what kind of walls are between you and the other person? 

 

[BoxCar]

The glass in the building may also limit RF signals as some glass has filters to limit radiation.

[Lscott]

Don't forget about the effect from the apartment's building materials. If you have cement walls there is likely rebar in it, wood and brick may have foil backed isolation in the walls, metal tint on the windows, high lead content glass, metal blinds etc. Some newer construction has sheet metal wall studs in place of the old wood ones as another item. There is a pile of construction material that can screw with a UHF signal. 

The building where I work has two of the above, poured concrete walls with a loose metal mesh and the office walls have metal studs. Needless to say the reception is rather poor for weak signals for anything other than a signal a mile or so away, and trying to TX is worse.

[IanM]

I'd give it a shot again with at least one transceiver out-of-doors. You should be getting some reasonable range. 

I'm in a very urban area and have no problem hitting and being heard on some of the in-town repeaters with the 905 and stock antenna. And I'm on the ground floor of a aluminum-clad apartment that is a black hole for cell reception. Up on the 6th floor roof deck, I easily pick up a few repeaters 20+ miles away. 

 

@DeoVindice, the 805 and 905 are both superhet so there should be good reception. I find that indoors with mine, said 20+ mile, 50W repeater comes in just fine, but nobody can hear me. SO OP should at least be getting some reception. I'm guessing it's on the architecture of one or both locations. An apartment even up to 6 stories or so could be wood-frame construction, but a commercial building at that height almost certainly has more steel in it, either structurally or with interior studs and cladding.

That said, envious of your commercial radio collection—very tempting to drop the bucks on one of those FPP Motorolas eBay keeps wanting me to see, but the Wouxun are working fine for me. Hope the OP gets better results in different conditions.

[BKmetzWRKZ843]

I have a Wouxun KG-935G with a Nagoya NA-771G antenna. I can usually hit one repeater (500ft tower) 35 miles away in a 2nd story room standing next to a window. On my back porch I can hit another repeater (60ft tower) 25 miles away. When I'm making contact, it's a weak signal but usually audible. Evenings are better than daytime and moving a few inches can make a big difference. I haven't had a chance to meet any one local yet to try simplex.

My house has vinyl coated steel siding so it's essentially a Faraday cage. Magnets easily stick to the siding. Windows are double pane with no tint.

[TOM47]

 

1 hour ago, BKmetzWRKZ843 said:

I have a Wouxun KG-935G with a Nagoya NA-771G antenna. I can usually hit one repeater (500ft tower) 35 miles away in a 2nd story room standing next to a window. On my back porch I can hit another repeater (60ft tower) 25 miles away. When I'm making contact, it's a weak signal but usually audible. Evenings are better than daytime and moving a few inches can make a big difference. I haven't had a chance to meet any one local yet to try simplex.

My house has vinyl coated steel siding so it's essentially a Faraday cage. Magnets easily stick to the siding. Windows are double pane with no tint.

 

 

1 hour ago, BKmetzWRKZ843 said:

I have a Wouxun KG-935G with a Nagoya NA-771G antenna. I can usually hit one repeater (500ft tower) 35 miles away in a 2nd story room standing next to a window. On my back porch I can hit another repeater (60ft tower) 25 miles away. When I'm making contact, it's a weak signal but usually audible. Evenings are better than daytime and moving a few inches can make a big difference. I haven't had a chance to meet any one local yet to try simplex.

My house has vinyl coated steel siding so it's essentially a Faraday cage. Magnets easily stick to the siding. Windows are double pane with no tint.

 

JUST DID A RADIO CHECKS FROM TWO KG-905G'S WITH THE SAME NAGOYA ANTENNA AND A KG-935G WITH STOCK ANTENNA.  NEGATIVE CONTACTS USING THE KG-906G'S  HOWEVER MADE LOUD AND CLEAR CONTACT WITH THE KG-95G TO A REOEATER AT LEAST 45 MILES DISTANT FROM AN INTERIOR 1ST STORYBEDROOM WOOD FRAME STUCCO CONSTRUCTION. 

[BKmetzWRKZ843]

On 9/30/2021 at 1:06 AM, TOM47 said:

JUST DID A RADIO CHECKS FROM TWO KG-905G'S WITH THE SAME NAGOYA ANTENNA AND A KG-935G WITH STOCK ANTENNA.  NEGATIVE CONTACTS USING THE KG-906G'S  HOWEVER MADE LOUD AND CLEAR CONTACT WITH THE KG-95G TO A REOEATER AT LEAST 45 MILES DISTANT FROM AN INTERIOR 1ST STORYBEDROOM WOOD FRAME STUCCO CONSTRUCTION. 

WOW! I am SO glad I bought the KG-935G! It's been a great radio for me. It's also my first Chinese radio. I had some trepidation about buying any Chinese radio but so far, (knock on wood) it's exceeded my expectations.

[SteveW]

On 9/27/2021 at 8:42 PM, fillmoreranger said:

Hi…

I am new to GMRS. I recently purchased two Wouxun KG-905G HT radios (buytwowayradios.com), replacing the stock antennas with the Nagoya NA-771G. I reside in a suburban subdivision. For my initial test (running 5w on Ch 5), I took one radio to a 3rd floor unit in a building 0.9 miles away, per Google Maps (a bit shorter as the crow flies). I expected a clear signal at that distance, but was not the case. My TX’s were not received by the 3rd floor unit. Their TX’s were hit or miss. Some came through (with static), others did not.

The only impediment I can really think of is a line of those massive overhead electrical power lines that cut across the two locations. 

Would that be enough to knock out a signal between these relatively short distance locations? Any suggestions to improve communications?

Obviously, a disappointment starting out.

Thanks in advance.

 

I have a theory, that people recommend the Nagoya NA-771 series of antennas just based on them being mentioned so often, not necessarily that they are truly better performers.  I don't have the GMRS version of that antenna, but I tested the 2M/70CM amateur band version on a BaoFeng BF-F8HP (UV-5R 3rd Gen) radio.  The radio's included antenna (improved over the typical, earlier-generation Baofeng antenna) works better than the Nagoya.  And, the long bendy whip of the Nagoya makes the radio fall over if jostled.

I just got a Wouxun KG-935G.  It comes with an improved, higher-gain antenna, and its performance is so good, that I wouldn't consider changing it.  The radio with its stock antenna has much better receive performance than my Retevis 76P with it stock antenna, and somewhat better than the 76P with a Smiley Super Stick IV. https://www.smileyantenna.com/product-p/46510.htm

I haven't tested the Smiley antenna yet on the 935G, because the Retevis has the opposite gender SMA connector, but my guess is that it would perform even better than the stock antenna on the Wouxon, since it can be extended longer.

I'd contact BuyTwoWayRadio and ask if the 905G uses the same antenna as the 935G, and if not, can you buy the 935G antenna.

https://baofengtech.com/product/nagoya-na-771/

[mbrun]

I have no objective feedback on whether it performs better, but the stock antenna of the KG-935G is definitely longer than the KG-905G antenna. See the image below.



Note that the KG-935G antenna is nearly the exact physical size of a Nagoya 701 GMRS antenna.

From range testing I did last year on the 771, I concluded it was indeed a higher performer, but through use have also concluded that the nominal addition distance I got (perhaps 5-10%) did not outweigh the consistent inconvenience of its length. I have returned to the use of the more convenient stock antenna.

Every radio enthusiast has a dream of obtaining a miracle antenna that will extend the range of their HT significantly. But truly, the only miracle product for improving GMRS range is the one results in your antenna being installed high and above all or the vast majority of obstacles between the transmit and receive antenna. The minor RF gain differences between HT antennas is so small most would not be able to honestly discern the difference (think princess and the pea here). Under the best of circumstances there is perhaps 157dB (+/-) of usable level range between two 5W HTs communicating with one another. If that difference gets eaten in one mile using a stock antenna, how much further are you going to get if that potential difference is increased by a mere 2dB from the use of a slightly improved antenna?

To the original poster. You have learned a hard lessen. Simplex range HT-HT is very limited in the real world, and it will very every where you go. Every obstacle between one antenna and another reduces range. Every tree, bush, window, wall, roof, hill, sign, person and other physical obstruction between two antennas contributes to this. So far, in my use in outdoor settings, the maximum distance I have learned I can reasonably count on is only about 1/2 miles using a pair of 5W HT. Beyond that it is a complete crap shoot with decreasing odds. Perhaps 3/4, 1, 2, 3 miles and more are in-fact possible. When at least one of the antennas in a link gets raised to higher and higher elevation the number of and the degree of obstacles between them naturally decreases. As this occurs effective range increases.

It is for this reason that repeaters are so prized in GMRS. They are prized when the owner places its antenna high on a tower, atop a building or a mountain top. That antenna is now way above the obstacles and is then free to travel great distances until the horizon of the earth finally stops it.


Michael
WRHS965
KE8PLM

[fillmoreranger]

Thanks to everyone who chimed in. Many of you provided interesting insights from your experiences. You have given me more to think about, going forward. I am new to both GMRS and as of last night, Amateur Radio. Yes, I am disappointed that my initial simplex target (family member) on GMRS was a failure at one mile away with my new KG-905G HT’s. I guess I have much to learn as I continue venturing into my new hobby… lol.

For those familiar with the DFW Metroplex, I am in far SE Arlington at TX-360. I also tried hitting the downtown Dallas and South Arlington GMRS repeaters, to no avail. Due east of me, I see the massive antenna farm in Cedar Hill. Unfortunately, I don’t think there are any GMRS repeaters there. 

Yes, tall repeaters are coveted assets in GMRS. Apparently, GMRS does not seem to be so popular on the south end of the Metroplex, where I live. At least not yet… lol. I may plant an antenna in the attic (HOA) and see if that helps… Or perhaps a mag mount on my SUV for some mobile signal scouting. I am not giving up on GMRS!

I did obtain some instant gratification last night on Amateur Radio, yakking from home on the Mansfield 440 machine with my starter BF-F8HP. I was unable to open the MJARS 2m machine. (I see a FT-60 in my future… lol)

The adventure has only begun!

 

 

[mbrun]

Congratulations on getting your ham ticket.


Michael
WRHS965
KE8PLM

[MichaelLAX]

2 hours ago, fillmoreranger said:

Thanks to everyone who chimed in. Many of you provided interesting insights from your experiences. You have given me more to think about, going forward. I am new to both GMRS and as of last night, Amateur Radio...

 

Congratulations!  Your new ticket should open up many repeaters to you in a metropolitan area:

Take a look at the Anytone AT-779UV a/k/a Radiodiddity DB-20G:

For $99 retail, you get 18 watts, instant ability to use base or mobile (cigarette lighter plug, fits in palm of hand and can use cup-holder mount) and easily opens up to allow 440 MHz, 2 meters and GMRS and MURS.

I program in all of my favorite repeaters and simplex and scan to find some action!

I love to drive to other areas and go repeater hunting and am surprised sometimes that with 18 watts at home (I have two of these for ease) with my rooftop Comet tri-bander, I can hit some of these newly discovered repeaters at home! 

 

[OldRadioGuy]

I have both the Nagoya 771 and the Smiley super stick (and the stock 805G rubber duck).  The Nagoya 771 and the Smiley (fully extended) seem to perform about the same and both are significantly better than the stock antenna.  I think the Smiley retracted is at least as good as the rubber duck.

As for the range of your 905G...   There are lots of metal foils (on insulation and foil backed drywall) and "see through" metal coatings on glass used in commercial buildings and high rise apartments.  Texas has a lot of intense sun and hot weather so many windows will have the metal coatings.  These will just eliminate your GMRS signal.  So I would not judge the radio by that.

Take the radios outside and test them.  Even our cheap FRS radios will do a mile... and that was inside the car with no external antenna.  Terrain and metal surfaces are your two worse enemies. 

Vince

 

[DeoVindice]

That's definitely worse performance than I would expect. From inside a second-floor apartment to another portable outdoors, two miles simplex is easy with a good antenna (I use a Smiley Super Stick IV). I'm sure we could go further if desired as RSSI is excellent when using the Smiley. The path is across a mixture of urban and suburbs, with a couple farm fields thrown in for good measure.

I'll grant that we're both using public-safety-grade radios with double-conversion superhet receivers. I'm not familiar with the architecture of the KG-905G so you could have a receiver overload situation if it's a direct-conversion/SoC deal. Have you repeated the test with the stock antennas? Better antennas have been known to cause overload when used on radios with poor selectivity.

As stated before, excessive objects between the two stations will also impact range.