additional ground radials to a base antenna ???

[BOOTY MONSTER]

in trying to learn more about antennas and how they work its seems that you basically can't have too many ground radials on a base . some pork butts (hams) even dig up their yards to bury rf ground wires and pipes . not to be confused with electrical grounding from lighting . so im wondering if a typical metal 5/8 , like a maco 5/8 would benefit from having say 3 or 4 additional sloping (45 degreeish) 108 inch ground radials attached to a non conductive guy system running from the antennas four 90 degree ground radial section ? effectively having 7 or 8 ground radials . its my understanding that 45 degree radials help the antenna tune to a 50 ohm impedance better . of course there are exceptions to everything but in typical situations........ .

will having more radials but at different angles help , hinder or make little to no difference ?

thanks

 

[Beetle]

Experiment and see what works for you.

Best advice this "pork butt" can offer.

 

[hookedon6]

dig up my yard:headbang:headbang sounds like a lot of work

...i used a gas powered sidewalk edger to make nice slits and then just dropped the wire into it.

 

[Robb]

Having more radial on the Maco would force focusing of more even wave propagation. But IMO - that is a fine antenna as is.

Hams do it for entirely different reasons.
If pork butts (lol!) are putting down ground radials, it is because:
They have a vertical antenna that requires it, such as the Hustler 6BTV and others like it. Most - but not all - of the verticals used by Hams will say that it is necessary for the antenna to be able to tune in to different bands. Even the mfg's say that it is necessary. It's a trade-off of the antenna design - one of the reasons that I haven't bought an antenna for my Ham rig so far.

Verticals for CB's can offer gain; not necessarily so for Ham antennas. A lot of them struggle just to get to unity gain - and some don't even come close. The nice thing about CB/10 meters id that the antenna length requirement is much shorter, so that antenna gain from a vertical is possible. I'm thinking about a Yagi or a beam for my Ham setup, just so there will be SOME antenna gain. Ham radios just aren't as efficient with power as CB, 10 meter, 6 meter, and 2 meter is.

 

[BOOTY MONSTER]

thanks folks . btw , i say pork butt just for friendly ribbing . i have a lot of respect for hams .

 

[W5LZ]

There are points of diminishing returns. When it gets to the point where it's just not worth the time/effort for so little 'improvement' resulting from that time and effort, it's time to quit.
There's also a practical side to it. That 'practical' relates to how much 'improvement' there is and what's the cost of that improvement. That cost isn't necessarily money, it also includes effort and what has to be done to other things to do what you want to do with this thing, sort of. Somewhere, you will stop and think, "I did all that just to get this?". There are some things that I just don't consider worth the effort that others sort of take for granted. Part of that is just laziness, and some of it is I just don't see enough advantage to do whatever it is. And then, some of it is, "You want me to pick up WHAT, by the clean end?" sort of thingy. Then again, sometimes I just want to see what happens if I do this-n-that. Curiosity can get you into more problems than some people would ever believe. As long as you are willing to pay for it, why not? But there are limits...
- 'Doc


I've found a lot of my 'top' limits. Still working on the lower ones. And there are some things I just ain't gonna do!

 

[Master Chief]

Having more radial on the Maco would force focusing of more even wave propagation. Ham radios just aren't as efficient with power as CB, 10 meter, 6 meter, and 2 meter is.

Rob, almost every one of your posts concerning antennas is full of misinformation. You need to learn more about antennas before spreading your poison. Your two comments above are just examples of your lack of knowledge.

Now to answer the original question, which is actually two separate topics......ground plane antennas (Maco) and ground mounted verticals (buried radials)

so im wondering if a typical metal 5/8 , like a maco 5/8 would benefit from having say 3 or 4 additional sloping (45 degreeish) 108 inch ground radials attached to a non conductive guy system running from the antennas four 90 degree ground radial section ?

The answer is NO.

We are speaking about a "ground plane" antenna in this thread. A ground plane antenna takes the "ground" up the mast with it. Professional tests have shown that there is a significant increase in performance when upgrading from 3 radials to 4 radials. However, there was not any significant advantage going past 4 radials. While more radials will not hurt, the cost and weight are counterproductive......just as Doc said.

Ground mounted HF antennas use many ground radials to increase coupling with the earth. After all, its all about the earth (ground).

Sloping radials down to 45 degrees will move the feedpoint closer to 50 ohms. On the Maco, the impedance matching is done with the tuning ring. Sloping the radials is useless in this design.

4 radials on the Maco is plenty and works as designed. Don't mess with it.

 

[Marconi]

Heck Master Chief, I wanted to ask brother Ron to give us some incite on what "even wave propagation" is all about.

I think maybe you are right in you perceptions though.

Maybe he had a good idea and just used a bad choice in words. Then again maybe I’m wrong. I doubt now he will come back with the Master Chief on his trail.

 

[Robb]

Rob, almost every one of your posts concerning antennas is full of misinformation. You need to learn more about antennas before spreading your poison. Your two comments above are just examples of your lack of knowledge.

Now to answer the original question, which is actually two separate topics......ground plane antennas (Maco) and ground mounted verticals (buried radials)

The answer is NO.

We are speaking about a "ground plane" antenna in this thread. A ground plane antenna takes the "ground" up the mast with it. Professional tests have shown that there is a significant increase in performance when upgrading from 3 radials to 4 radials. However, there was not any significant advantage going past 4 radials. While more radials will not hurt, the cost and weight are counterproductive......just as Doc said.

Ground mounted HF antennas use many ground radials to increase coupling with the earth. After all, its all about the earth (ground).

Sloping radials down to 45 degrees will move the feedpoint closer to 50 ohms. On the Maco, the impedance matching is done with the tuning ring. Sloping the radials is useless in this design.

4 radials on the Maco is plenty and works as designed. Don't mess with it.

Hey, Master Chief, You are full of yourself!
Spreading poisen? No; I offered my opinion - and this is a FORUM.
Aw, I can forget about it!
Done.
Also I pointed out was that BootyMon had wondered why Hams go the route of burying radials. What I wrote was correct - taken in context.

If everyone knew as much about radio as you did, this forum would be unneccessary. Good for you. You come on this forum every once in a while and pass out the brown biscuits as you please - and I don't don't bite. Few - if any people on this forum does. On another thread on this forum, you are defending Freecell. Fine; but that doesn't help Pumphouse get his stuff any faster. Truth be told, waiting six or seven months for a business transaction to occur isn't defendable. Furthermore, since Freecell has displayed such behavior twards a customer - I certainly will NOT have him do any work for me. I had planned to send him my CPI - but there's no chance of that now. If he isn't coming up with what he promised, he shouldn't be making them. There are a lot of hungry techs out there that can do just as good as job without creating unneeded drama that come with the goods in a timely fashion.

 

[Moleculo]

Guys, lets not turn this place into [insert other forum name here]. There is a way to offer knowledge and opinion without attacking other forum members.

Keep the threads ON TOPIC without adding personal insult to the posts. Refer to the forum FAQ, if necessary.

I have made this request too many times in recent weeks. As a result, I must now use poignant examples of which parts of posts are viewed by most as personal attacks:

You need to learn more about antennas before spreading your poison. Your two comments above are just examples of your lack of knowledge.

This particular part of the post neither adds value to the discussion, nor does it encourage others to ask questions and offer opinion. It also demonstrates an inability to be tactful, as well as a lack of respect for what this site is all about, which is helping each other. The rest of the post was valuable and served to correct some misinformation, but many will never get past those two sentences.

When posting, please remember this part of the site FAQ:
"Courtesy and respect toward others are expected of everyone"


I don't enjoy making posts like this, but I will continue doing so as long as the personal attacks continue. I will not allow this place to turn into [insert any forum you dislike here].

 

[Cajun Invader]

Booty, I am currently experimenting with basicly the same idea as you.

I insulated my antenna from it's mast by using a shovel handle made of wood shoved into the top of the mast. I then attached the antenna to the handle.

I have taken 4 pieces of 10 gauge wire 9' long and attached them to the base of my Imax. I then tied fishing line to the end of the wire and pulled them out as far as I could and tied them off. I used bricks to do so.

On my feed line I made a choke by taking a 6 1/2' piece of RG213 coax and winding it 8 times around a 4" piece of PVC.

I have two stations in my area that I can rely on for accurate reports. One is 17 miles to the North and the other is 5 miles to the South East. Over 3 days they are going to report my signal strength back to me and I will take note of theirs and log. Also I will be asking 2 neighbors, both relatives to check for interference in their homes. This will be done this weekend. I then will remove the wire and choke and retest the following weekend and compare the information.

After I do my experiment then I can judge for myself whether it works for me or not.

I'm starting to like this hobby more and more now that I am learning some of the theory behind it.

I'll post my results when I have concluded the testing.

Thanks to all who have helped me with this. Especialy the guy across the pond.

 

[74IN]

a shovel handle

Will that end the local excavations?:laugh:

 

[hookedon6]

Hams do it for entirely different reasons... it is necessary for the antenna to be able to tune in to different bands....

about the only antennas that can physically "tune in to different bands" are the stepIR's and the screwdriver type antennas.

buried radials are used to improve the efficiency of a marconi antenna (by reducing the ohmic losses) and to provide the "other half" of the antenna (so the antenna can "push" RF against ground).

believe it or not, on a ground mounted BTV antenna ,as you add more radials (and don't make any other changes), you reach a point where the VSWR actually starts to RISE as you add more radials..... and that is what you want.

 

[W5LZ]

Wanna try a quick-n-dirty antenna that works? Takes about 20 feet of wire, an SO-239 connector, a tree, and some string.
Cut a 9 foot piece of wire and solder one end to the center pin of that SO-239. Cut the remaining wire so it's about 18 feet long, thread one end of it through one of the mounting holes for that SO-239 connector. Position wire so that it's of equal length hanging from that '239 (9 feet each side). Twist wire so that it isn't going to come loose from the '239. Make loops in the 'other' ends of those wires, so you can tie string to them. Throw string on the center pin piece of wire over highest limb in that tree that you can. Haul the whole mess up sort of high as it'll go. Spread the 'legs' hanging down with the string tied to them so that you get as wide a 'spread' between those 'legs' as you can get. Uh... should have said connect feed line to that SO-239 before hauling it up into that tree, sorry.
Guess what you do from that point?
The 'angle of the dangle' of those legs will change the SWR, adjust to whatever you think is best. What angle is best? Whichever one gives the lowest SWR.
How do you get any cheaper than that?
Soldering things will help to some extent, or just twist things tight. 14 ga. wire works okay, whatever will fit through the holes in that SO-239, or 'wobble' out that hole a little. Cost just depends on what you might have laying around.
TA-DA! One 1/4 wave groundplane antenna. It'll work as well as any other 1/4 GP at the same height. Pink insulation works best, if you can find it, it's rare you know...
- 'Doc

 

[morseman]

When using an an elevated vertical such as a maco v 5/8 etc there is no advantage to adding more radials, if using a ground mounted vert. then extra ground radials are a must to offset ground losses.Elevated verticals are not affected by ground losses as much and 3 to 4 radials at 1/4 wave length are fine= about 108 inches for 11 meters.
Bob