effective dual band yagi for gmrs

[scottmckinney67]

IMHO - you don't have an antenna problem. You've got a radio problem. 3.5 miles with 40 watts in relatively flat terrain in mid Ohio is not a line of sight problem.

 

Those Midlands are quite honestly garbage. You are going to spend a lot of time (and money) trying to make those units perform like actual radios should. Go buy some used Kenwood/Motorola/Vertex radios programmed to GMRS (which will end up costing half as much and work three times better).

 

I understand that my radios aren't all that, especially when it comes to receive sensitivity, but that line of sight app link that I posted contradicts that it's solely a radio problem.  I do appreciate the feedback, and I will get better radios at some point.

[marcspaz]

IMHO - you don't have an antenna problem. You've got a radio problem. 3.5 miles with 40 watts in relatively flat terrain in mid Ohio is not a line of sight problem.

 

Those Midlands are quite honestly garbage. You are going to spend a lot of time (and money) trying to make those units perform like actual radios should. Go buy some used Kenwood/Motorola/Vertex radios programmed to GMRS (which will end up costing half as much and work three times better).

 

Kenwood and Moto are good... but Vertex Standard?  On their own, under Moto or Yaesu, I was never a fan.  I still have one of their tuners and its better at creating RFI than a proper LC network.  LOL

 

He is using a Midland mobile mag mount antenna in the house.  Regardless of the radio in use, I am fairly confident the lack of a proper antenna is an issue.

[marcspaz]

I understand that my radios aren't all that, especially when it comes to receive sensitivity, but that line of sight app link that I posted contradicts that it's solely a radio problem.  I do appreciate the feedback, and I will get better radios at some point.

 

He brings up a good point.  The Gen 1 MXT400's were problematic.  My Gen 1 broke the first day I had it.  It was deaf and power was weak.  It dropped off 100% after a few minutes of use.  most people reported all kinds of issues with the gen 1's drifting and not being able to get proper audio into repeaters.

 

I had three Gen 2 MXT400's.  All of them worked great.  I get 5+ miles mobile to mobile (depending on terrain), I am full quiet into a repeater that is 22 miles from my house.

 

Do your mics have loops for hanging or button style to go on a 2 prong hook?

[scottmckinney67]

Just spoke to a guy that I really respect and know is knowledgeable on the subject.  Here's our game plan:

1. Ditch midlands on both sides.

2. Use my diamond dual band mobile whip in my attic.  It has a better base with better cable than the midland base and I can tune it slightly for better results.

3. Buy my son an omni dual band that can be tuned, tune it,  and get it above his roof line.  I'll use 25 feet of RG8U or LMR400, ground antenna, and lightning arrester.

4. Test and hopefully enjoy good results

 

Wish me luck!

[scottmckinney67]

He brings up a good point.  The Gen 1 MXT400's were problematic.  My Gen 1 broke the first day I had it.  It was deaf and power was weak.  It dropped off 100% after a few minutes of use.  most people reported all kinds of issues with the gen 1's drifting and not being able to get proper audio into repeaters.

 

I had three Gen 2 MXT400's.  All of them worked great.  I get 5+ miles mobile to mobile (depending on terrain), I am full quiet into a repeater that is 22 miles from my house.

 

Do your mics have loops for hanging or button style to go on a 2 prong hook?

 

I'm only using midland antennas.  I have Retevis RT-99's for the mobile radios.

[marcspaz]

I'm only using midland antennas.  I have Retevis RT-99's for the mobile radios.

Ah... got you.  I thought you had a Midland radio, for some reason.  I have zero experience with those.  The Midland antennas are not great, unfortunately. 

[scottmckinney67]

Update: bought a tram 1480 for my son's house.  Going to get that sucker off the ground, probably 16-20 feet.  Using this cable https://www.dxengineering.com/parts/DXE-400MAXDX050 on both our antennas.  I'm mounting my midland whip on a ground plane kit in the attic.  I hope the Tram does the job.  We shall see 

[marcspaz]

That Tram is a monster antenna.  That should do the trick.  The ground plane kit is going to be a huge improvement on your side too.

 

Good luck.  Looking forward to hearing back with the results.

[gman1971]

Nah, the Diamond X500N would've been an even bigger monster antenna...

 

G.

[scottmckinney67]

That Tram is a monster antenna.  That should do the trick.  The ground plane kit is going to be a huge improvement on your side too.

 

Good luck.  Looking forward to hearing back with the results.

 

Thanks.  Hopefully the SWR is low enough to not make our Chinese radio go kaboom haha.

[scottmckinney67]

Update: just tested SWR of the tram 1480 on my little nanovna contraption from 460-470 MHz, highest SWR was around 1.7 at the top, got as low as 1.3 towards the bottom.  So no radio kablooey   We'll get her sealed up, mounted and grounded soon at my son's house and see what we've got.

[scottmckinney67]

Ok.  I installed a nagoya ground plane kit on my midland mobile 6db whip in the attic and ran 50 feet of LMR400.  Installed a tram 1480 base antenna at my son's.  It's approximately 22 feet off the ground, above his roof line, 50 feet LMR400.  We can talk clearly on 3 GMRS channels. The others are very noisy.  There is a noise floor on those three, but the voices are clear and legible.  I was concerned about the Tram not being tuned for GMRS, but the SWR was low according to my cheap analyzer so I went for it.  I'm glad I did, because this gets us talking and has him ready for amateur bands when we get our tech licenses.  When we do, I'll swap the attic midland for a dual amateur band nmo mobile and we're all set.  Also, I am able to hit some vhf and uhf repeaters in my area (within 10-15 miles) with my midland  antenna on low power.  I didn't try at his mom's but I suspect his set up will be much better as he's closer to downtown Columbus and his antenna has more gain.

 

I'm liking these Retevis mobile radios.  They're very easy to program with a tablet or phone.  Once you get them programmed, you don't need them.  You can change channel, volume right from the mic and the mic tells you the channel.  The audio sounds fine to me.

 

Thanks for all the help and suggestions! 

[Soladaddy]

What model is the radio? I see a 90 and 95 but no 99. I'm late to the game but there are a few dual band antennas for GMRS, but they are paired with MURS because GMRS is a 3 harmonic of MURS. With dual band antenna the focus is on the VHF side and the UHF just resonates so its usually not a good performer. If you focus on 440 ham and gmrs you can find some 1/4 waves that are very broadband a could cover both. I have a Comet mobile CA-2x4SR that is broadband enough to cover 2M, MURS, 440, and GMRS. It has a very flat SWR across all bands and does well on the VHF bands. I need more testing to make a UHF performance claim. Glad you are making it work.

[scottmckinney67]

I'll leave radio and compliance aside for now   I was able to talk with the Tram and the little whip but I've since bought my son a pctel maxrad 5 element yagi that's resonant on gmrs.  I used google maps, switched to satellite view and drew a line on the map between his house and mine.  That was super helpful in getting it aimed.  If someone knows an easier method, let me know.  With that antenna, I was able to talk to my son almost all the way to my house with a baofeng hand held in my truck.  That's more like it   I went ahead and ordered another for my house and will aim them at each other and hopefully get good results.  When I get some definitive results, I'll post them up for future reference.  This is the antenna https://www.amazon.com/gp/product/B007JSD5G2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1  It seems to be well made, welded elements and I like where the connection is compared to some others.

[Soladaddy]

I use Googe Earth for bearing, distance and it will give an elevation profile which is great for line of site issues. While I like the jack of all trades antenna concept, your single band yagi will perform much better and its much smaller.  I plan on using a better GMRS only omni antenna at home (currently using a copper j-pole). For radios, looking for a couple mobiles.

[scottmckinney67]

I use Googe Earth for bearing, distance and it will give an elevation profile which is great for line of site issues. While I like the jack of all trades antenna concept, your single band yagi will perform much better and its much smaller.  I plan on using a better GMRS only omni antenna at home (currently using a copper j-pole). For radios, looking for a couple mobiles.

I've been using this for simple line of sight.  https://www.scadacore.com/tools/rf-path/rf-line-of-sight/   I like it.  I'm sure the gmrs yagi is the way to go, I was just trying to save some time and money finding a dual band.  The tram showed pretty low SWR for gmrs frequencies but the performance on gmrs is so so, I think.  I did try to hit a standard uhf repeater in the area and was able to hit one about 25 miles away with it.  If it stays sealed up, I think it's a keeper for a standard dual band omni.

[scottmckinney67]

Update.  Installed yagis on both ends.  We can understand every word on every channel now.  Next phase, raising both by 6 feet and make sure the aim from mine is good.  I was actually out on the roof in my underwear re-aiming it just now haha.  I did the map aim and drew a straight line but didn't have a vantage point for beyond my house, garage roof mount on existing dish antenna j mount with a piece of toprail that probably barely clears the apex of the main roof, and it may not, didn't get on main roof to look.  I think I'm close to aimed but I don't think I can get much improvement with a little more height.

 

Stay tuned 

[Logan5]

I've been using this for simple line of sight.  https://www.scadacore.com/tools/rf-path/rf-line-of-sight/   I like it.  I'm sure the gmrs yagi is the way to go, I was just trying to save some time and money finding a dual band.  The tram showed pretty low SWR for gmrs frequencies but the performance on gmrs is so so, I think.  I did try to hit a standard uhf repeater in the area and was able to hit one about 25 miles away with it.  If it stays sealed up, I think it's a keeper for a standard dual band omni.

Thank you sir. I love it.

[Soladaddy]

That is a nice app. Congrats, you have the radio bug. With most systems, the antenna and feedline are to most important and even more so with UHF. This makes me want to buy some LRM400.

[gman1971]

Works if you're a "flat earther" as it doesn't seem to take into account Earth's curvature, nor the 4/3rds of Earth curvature for radio waves propagation, etc. Radio Mobile Online seems to be a better free option, JMHO.

 

According to the app, the Madison WI, Candelabra tower @ 330 meters tall  (~1400 feet) has "line of sight" down to Chicago...  and a 1 km tower in the same place should have line-of-sight all the way to Spain, from Madison WI... not sure if that's right... LOL

 

G.

[scottmckinney67]

Works if you're a "flat earther" as it doesn't seem to take into account Earth's curvature, nor the 4/3rds of Earth curvature for radio waves propagation, etc. Radio Mobile Online seems to be a better free option, JMHO.

 

According to the app, the Madison WI, Candelabra tower @ 330 meters tall  (~1400 feet) has "line of sight" down to Chicago...  and a 1 km tower in the same place should have line-of-sight all the way to Spain, from Madison WI... not sure if that's right... LOL

 

G.

 

Thanks for the info.  It at least got me in the ballpark.  

[russwbrill]

Thanks for the responses guys.  What about an omni 70cm/2M that would have a decent SWR on GMRS frequencies?  If I got a taller omni on my end, and could possibly raise his whip some, think that would work.  I don't plan on GMRS being our band of choice but it's what we're licensed for at this point.

 

Unfortunately, you really need a Mono-band antenna to get the most out of your height restricted situation. Hustler makes the G-6 ( Model G6-450-3 ) UHF Omni-directional antenna with 6 dbd of gain, If you can install the G-6 at your place, you might make up for the other stations lack of height above ground.. Also, low loss coax like LMR-400U and N-Connectors can go a long way in reducing signal loss..

 

Note: I noticed (after this post, duh..) in an earlier post you have installed a set of Yagi antennas to solve your problem. However, if you can accomplish the same results with a better Omni and better coax, you'll start to hear what you're missing with directional antennas.. Just my 2 cents...

 

73,

Russ

[scottmckinney67]

Unfortunately, you really need a Mono-band antenna to get the most out of your height restricted situation. Hustler makes the G-6 ( Model G6-450-3 ) UHF Omni-directional antenna with 6 dbd of gain, If you can install the G-6 at your place, you might make up for the other stations lack of height above ground.. Also, low loss coax like LMR-400U and N-Connectors can go a long way in reducing signal loss..

 

Note: I noticed (after this post, duh..) in an earlier post you have installed a set of Yagi antennas to solve your problem. However, if you can accomplish the same results with a better Omni and better coax, you'll start to hear what you're missing with directional antennas.. Just my 2 cents...

 

73,

Russ

We're still tweaking.  My antenna is approximately 27 feet off the ground.  His around 15.  He can hear me perfectly with very little noise.  I can hear him legibly but with a good deal of noise.  Going to raise his another 6 feet and verify the aim of my yagi, then probably call it a day with the GMRS setup.  Nice thing is, we've found another GMRS buddy and can talk simplex so that's encouraging.  We both hit him.   We're getting tech licenses and will switch back to omni's on both sides and probably go VHF.