Antenna selection home base station

[WRWJ577]

I'm new to GMRS and have found myself overwhelmed while researching antennas. I have chosen midland mxta26 for my mobile setup. Would that be fine for base station or should I do one of the longer fiberglass ones? Any help in this would be appreciated. Any questions I haven't thought about would also be appreciated.

[OffRoaderX]

It depends.. on many factors... BUT:

If you will be installing it on your roof, a large fiberglass type "base" antenna like the Tram1486 is probably a better choice as it will perform better and does not require a ground-plane.

If you just want to put it in the window, then the MXTA26 is probably a better choice as it is smaller and will fit in the window better than a 5-8Ft long fiberglass type base antenna and you can slap a pie-pan under it for the groundplane.

 

[WRWJ577]

I plan to use chimney strap and 5 foot pole to mount it. At least until I decide to bite the bullet on a tower. Thank you for your input. By the way I love you videos. I watch them instead of working some days

[Sab02r]

I'll second the recommendation for the Tram1486.  

I used my MXTA26 temporarily mounted to a porch railing, with decent results while awaiting coax...and decent weather.  Once the ice was off the roof, up went the new Tram.  The higher elevation provided vastly improved reception.

Keep in mind that the Tram will likely require some tuning for GMRS frequencies.  The antenna comes with very good tuning instructions that require you to take the antenna apart, carefully measure and trim each section accordingly, and then reassemble the antenna to test SWR.

Please trim incrementally, working your way to the measurement with the lowest SWR by trimming a small amount at a time and then reassembling and testing SWR.    If you trim too much...it takes forever to grow back 

I stopped trimming after three cuts when my antenna measured 1.16:1 SWR on the workbench.  On the roof, with new coax, it measured a high of 1.04:1.

I am certain that OffRoaderX has some excellent videos showing how to tune an antenna and measure SWR with the Fars-O-Meter 2000 for reference.

 

[WRWJ577]

Tram 1486 ordered thank you for the help. Searching deals on towers now.

[Sab02r]

After I had already built my own, I found this easy-to install, adjustable roof mount at home depot that may be cheap enough to use until you find a tower:

https://www.homedepot.com/p/Winegard-J-Pipe-Antenna-Mount-DS-3000/204701091

[nokones]

47 minutes ago, Sab02r said:

After I had already built my own, I found this easy-to install, adjustable roof mount at home depot that may be cheap enough to use until you find a tower:

https://www.homedepot.com/p/Winegard-J-Pipe-Antenna-Mount-DS-3000/204701091

Kinda like what I had done.

[MarkInTampa]

22 hours ago, nokones said:

Kinda like what I had done.

I was on Home Depots web site and stumbled upon 30ft aluminum telescopic flag poles yesterday. Figured if they can handle the wind loading of a 3'X5' flag without guy wires it should handle my GP-6 antenna also without guy wires. I also live in Florida where we have these things called hurricanes and would like the option to be able to be able to drop the height of the antenna if need be. Anybody try one of these?

 

[Sshannon]

34 minutes ago, markskjerve said:

I was on Home Depots web site and stumbled upon 30ft aluminum telescopic flag poles yesterday. Figured if they can handle the wind loading of a 3'X5' flag without guy wires it should handle my GP-6 antenna also without guy wires. I also live in Florida where we have these things called hurricanes and would like the option to be able to be able to drop the height of the antenna if need be. Anybody try one of these?

 

It’s certainly worth trying. Flagpoles like this are one way hams get around HOA rules.  I like the fact that it doesn’t require a couple yards of concrete like a self supporting truss type tower does.  I might try one.  I get occasional 10% off coupons from Home Depot too.

[Sab02r]

On 3/28/2023 at 8:53 AM, nokones said:

Kinda like what I had done.

I actually used your picture as a model for the one I built (THANK YOU VERY MUCH!!!).

I was surprised at how inexpensive the off-the-shelf Home Depot unit was, and bought it just to see if it was durable.  Turns out that it was prettier and handier than mine...and is doing a fine job of holding that Tram down, while my fabricated mount sits in the garage.

[nokones]

11 hours ago, Sab02r said:

I actually used your picture as a model for the one I built (THANK YOU VERY MUCH!!!).

I was surprised at how inexpensive the off-the-shelf Home Depot unit was, and bought it just to see if it was durable.  Turns out that it was prettier and handier than mine...and is doing a fine job of holding that Tram down, while my fabricated mount sits in the garage.

I'm glad that I could help.

[WRWJ577]

Thank you all for your suggestions. The flag pole idea has me thinking about codes and permits. Flag pole would probably be an easier sell.

[nokones]

I think the Flagpole is a great structure for an antenna. The placement will be critical insofar as the length of the cable run. Unless you plan to place it next to your home and very close to your radio room, you may want to consider using foam helix for your cable run. Although, the pole will be grounded by being placed in the ground, it is my understanding you still want a grounding system tied into your earth grounding point with the house.

[WRWR462]

On 3/29/2023 at 8:36 AM, markskjerve said:

I was on Home Depots web site and stumbled upon 30ft aluminum telescopic flag poles yesterday. Figured if they can handle the wind loading of a 3'X5' flag without guy wires it should handle my GP-6 antenna also without guy wires. I also live in Florida where we have these things called hurricanes and would like the option to be able to be able to drop the height of the antenna if need be. Anybody try one of these?

 

Since that's a 30ft aluminum pole I'm guessing that would make a good ground plane as well.

[Sshannon]

14 minutes ago, nokones said:

I think the Flagpole is a great structure for an antenna. The placement will be critical insofar as the length of the cable run. Unless you plan to place it next to your home and very close to your radio room, you may want to consider using foam helix for your cable run. Although, the pole will be grounded by being placed in the ground, it is my understanding you still want a grounding system tied into your earth grounding point with the house.

That’s correct. Aluminum oxidizes immediately and aluminum oxide is not a conductor. Having an aluminum pole in the ground doesn’t ground it. 

[WRWR462]

15 minutes ago, Sshannon said:

That’s correct. Aluminum oxidizes immediately and aluminum oxide is not a conductor. Having an aluminum pole in the ground doesn’t ground it. 

What if you sand it a bit to get the oxidation off and use a dieelectric grease? You don't really need a big piece for a ground plane for an antenna, like a foot or a little more right?

[Sshannon]

33 minutes ago, WRWR462 said:

What if you sand it a bit to get the oxidation off and use a dieelectric grease? You don't really need a big piece for a ground plane for an antenna, like a foot or a little more right?

A ground plane is not the same as grounding the antenna post. Conduction is not necessary. A 30 foot mast is way more than adequate as a ground plane for a 68 centimeter wavelength anyway. 

[WRUU653]

44 minutes ago, WRWR462 said:

What if you sand it a bit to get the oxidation off and use a dieelectric grease? You don't really need a big piece for a ground plane for an antenna, like a foot or a little more right?

It isn’t just about creating a ground plane for the antenna. There are grounding and bonding requirements at play here for a whole slew of reasons. 

Chapter 8 of the NEC (National Electrical Code) article 810 is a good place to start. 

https://www.amazon.com/National-electrical-code-2023-Paperback/dp/B0BJVN2YWM/ref=sr_1_19?crid=2FI33XQXFITCI&keywords=nec+2023+code+book&qid=1680190728&s=books&sprefix=Nec%2Cstripbooks%2C248&sr=1-19

this book from ARRL also. 

https://www.amazon.com/Grounding-Bonding-Radio-Amateur-ARRL/dp/1625951493/ref=asc_df_1625951493/?tag=hyprod-20&linkCode=df0&hvadid=552879161221&hvpos=&hvnetw=g&hvrand=15249024678358850374&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=1013639&hvtargid=pla-1461344866696&psc=1

be safe. 
 

[WRWR462]

25 minutes ago, WRUU653 said:

It isn’t just about creating a ground plane for the antenna. There are grounding and bonding requirements at play here for a whole slew of reasons. 

Chapter 8 of the NEC (National Electrical Code) article 810 is a good place to start. 

https://www.amazon.com/National-electrical-code-2023-Paperback/dp/B0BJVN2YWM/ref=sr_1_19?crid=2FI33XQXFITCI&keywords=nec+2023+code+book&qid=1680190728&s=books&sprefix=Nec%2Cstripbooks%2C248&sr=1-19

this book from ARRL also. 

https://www.amazon.com/Grounding-Bonding-Radio-Amateur-ARRL/dp/1625951493/ref=asc_df_1625951493/?tag=hyprod-20&linkCode=df0&hvadid=552879161221&hvpos=&hvnetw=g&hvrand=15249024678358850374&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=1013639&hvtargid=pla-1461344866696&psc=1

be safe. 
 

Thank you for this information 

[MarkInTampa]

3 hours ago, nokones said:

I think the Flagpole is a great structure for an antenna. The placement will be critical insofar as the length of the cable run. Unless you plan to place it next to your home and very close to your radio room, you may want to consider using foam helix for your cable run. Although, the pole will be grounded by being placed in the ground, it is my understanding you still want a grounding system tied into your earth grounding point with the house.

I just ordered one up. We shall see. Pole will be located 2ft away from radios on the other side of the wall, plan on digging a hole a few inches next to the house for the sleeve the pole inserts into as well as clamping it (even thought it should not need it) on the house around the 7ft or so mark. It will never be used for a flag (in the back of the house) just for radio antenna. Cinderblock wall is only 8ft or so from the ground with a flat roof. There is a old abandoned CATV ground block and intact ground rod 6 inches away from where the pole would be. There is also another ground rod 6ft away for the AC unit I can tie into as well. I want a 30ft or so pole that I don't have to mess with guy wires for a reasonable price ($150-170 depending on color). Rohn, MFJ and other 30-40ft poles sell for well over $299, require guy wires and a lot effort. I'm not in a HOA and can use anything I want but don't want to spend 4X the price of the antenna just on a mast.

I used Sika expanding fence post foam a few years ago when I replaced a fence at the old place and it worked GREAT! Didn't have to mix concrete, 1 bag equals 100 pounds of concrete. Sets up in 5 minutes or so. Thinking of using it for the flagpole sleeve instead of concrete. I was doing hurricane traffic signal repair and watched the power company plant poles with this kind of stuff instead of concrete. Any thoughts?

 

[Sshannon]

1 hour ago, markskjerve said:

I just ordered one up. We shall see. Pole will be located 2ft away from radios on the other side of the wall, plan on digging a hole a few inches next to the house for the sleeve the pole inserts into as well as clamping it (even thought it should not need it) on the house around the 7ft or so mark. It will never be used for a flag (in the back of the house) just for radio antenna. Cinderblock wall is only 8ft or so from the ground with a flat roof. There is a old abandoned CATV ground block and intact ground rod 6 inches away from where the pole would be. There is also another ground rod 6ft away for the AC unit I can tie into as well. I want a 30ft or so pole that I don't have to mess with guy wires for a reasonable price ($150-170 depending on color). Rohn, MFJ and other 30-40ft poles sell for well over $299, require guy wires and a lot effort. I'm not in a HOA and can use anything I want but don't want to spend 4X the price of the antenna just on a mast.

I used Sika expanding fence post foam a few years ago when I replaced a fence at the old place and it worked GREAT! Didn't have to mix concrete, 1 bag equals 100 pounds of concrete. Sets up in 5 minutes or so. Thinking of using it for the flagpole sleeve instead of concrete. I was doing hurricane traffic signal repair and watched the power company plant poles with this kind of stuff instead of concrete. Any thoughts?

 

If you do a thread on this I’ll subscribe. 

[MarkInTampa]

41 minutes ago, Sshannon said:

If you do a thread on this I’ll subscribe. 

How about a grounding question. I've got a spool of 14AWG sold and a spool of 12AWG stranded green ground wire laying around, don't know if that's good enough. Would you suggest grounding just the pole, run the wire up with the coax and ground just the antenna, do both or isolate the antenna from the pole using something like a PVC sleeve and ground just the antenna?

[WRUU653]

13 minutes ago, markskjerve said:

How about a grounding question. I've got a spool of 14AWG sold and a spool of 12AWG stranded green ground wire laying around, don't know if that's good enough. Would you suggest grounding just the pole, run the wire up with the coax and ground just the antenna, do both or isolate the antenna from the pole using something like a PVC sleeve and ground just the antenna?

No, it is not big enough.
 

Reference NEC. 
810.21 Bonding Conductors and Grounding Electrode Conductors — Receiving Stations.
The bonding conductor or grounding electrode conductor shall not be smaller than 10 AWG copper

I don’t want to understate importance of grounding and bonding. Reading material in my above post is a good idea.  

 

[Sshannon]

3 hours ago, WRUU653 said:

No, it is not big enough.
 

Reference NEC. 
810.21 Bonding Conductors and Grounding Electrode Conductors — Receiving Stations.
The bonding conductor or grounding electrode conductor shall not be smaller than 10 AWG copper

I don’t want to understate importance of grounding and bonding. Reading material in my above post is a good idea.  

 

This is absolutely correct.  A lot of people assume that if a tower is grounded at its base, it provides some level of protection, but it must be bonded to the electrical service ground system as well.  It's not uncommon to measure a voltage between two different points in the ground and without bonding, that voltage is being carried on the shield of your antenna feed line and through your radio equipment.

A simplified and illustrated reference that's pretty understandable is this one.  It refers to "Radio Telescopes" but don't let that hang you up:

https://reeve.com/Documents/Articles Papers/Reeve_AntennaSystemGroundingRequirements.pdf but the ones WRUU653 posted above are good to have as well. 

A denser article is the one I've attached below from Polyphasor.  It's not as easy to digest (at least for me), but it's more specific for some things. Some of the most important points, such as the importance of a single point ground, can be too easily overlooked.

Steve

 

1485-013.pdf

[WRUU653]

@Sshannon Really great PDFs.  What you say is true about bonding and potential between things. Bonding is often mistaken for grounding and while trying to avoid the rabbit hole into the topic and sounding like I am preaching I feel it is important for people to understand potential dangers exist and these codes and guidelines exist to keep people safe.