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Good evening gentleman,
I am new to this site,but not a novice ,25 years ago I built a 1/4 wave g/p outta 1/2 inch 6061 aluminum tubing,with 4 ground radials and it still whips my starduster and my maco 5/8 wave in local transmission every time!And I have went back and upgraded all the materials on both the other antennas any insight thanks!

good job!my maco is lacking but i am working on it.did you mean a 1/2 wave 16 feet or a 1/4 8 feet?

Strikesmith, your description is a little lacking for any good insight. How about a picture or two where we can see some details of your whipper-upper antenna.

Here are some images of a 1/4 wave radiator AT that I made. The more radials I added the better the antenna performed and the lower the frequency came down into the CB band with 102" elements. 102" elements will let you work nicely in the 11 meter band if the GP affect is strong enough. The weaker the GP is the higher the current flowing in the radials and the higher in frequency will the 102" radiator show to be. So, if you have to use a 106" or 108" to make resonance at or near 27.205, then your GP affect is not adequate and you will be sacrificing Field Strength. I believe this is also what folks find when the use full length 1/4 wave whips on mobiles where some work out fine with 102" and others need 106" and even more.

I believe the more radials you have the smaller the magnitude of the currents that flows in each GP element and the less affect these horizontal magnetic force currents have on the vertical electric force currents that flow in the vertical radiator, and that you should see an increase in the FS gain. I can't prove that this is what happens, but it appears to be what I make of what I saw.

I used a mobile mirror L-bracket as a feed point and a modified hub off of an A99 for the GP radials, which are also 102" whips. The image I think only shows 5 installed though, but it had 6 total, 3 slanted down and 3 horizontal, like a discone shape. The added tube (9" long) along side the mast was there to run the coax through so the slanted down radials currents wouldn't be getting on the feed line. The mast under the L-bracket was 2 - 10' mast that allowed me to mount the antenna at 20' to the feed point, and I was able to work all my regular buds out to as far as 50 miles most mornings and it worked just as good as my AstroPlane that I also had up at 20' to the feed point. This placed the tip height of the AP about 4.5' feet lower than my homemade jobber I called my Marconi6.

Just by having 6 radials instead of only 3, the antenna showed an increased in the Field Strength from 60uA to 140uA on my Heathkit PM-2, with the FS antenna on a 10' mast at 30 feet away. I think I would have seen more FS had I had this FS meter antenna up as high as the antennas. The point of my testing was what are the effects of adding more radials to a 1/4 wave radiator.

Attached Images

	Marconi - Starduster with sleeved balun..JPG (412.0 KB, 22 views)
	Marconi Starduster.jpg (21.3 KB, 24 views)
	Marconi with balun.jpg (327.9 KB, 19 views)
	Heath Kit FS Meter - RF.jpg (380.3 KB, 13 views)

When you start thinking about the possible range you can/do get from one particular type of antenna as compared to another type of antenna, there are a few things that you should keep in mind. Here are a few of those thingys, certainly not all by any means, and not even close to enough of those 'thingys' to even calculate more than just 'sort of right' cuz they ain't absolutely wrong. (If you really want a nightmare list of things to consider, take a look at the design characteristics for any of the NEC based antenna modeling programs.)
First, you are dealing with propagation, shape of the radiation pattern, the electrical characteristics of the various levels of the ionosphere AND the various states that ionosphere assumes under different conditions in solar 'flux', some trigonometry so you can figure reflection/refraction angles, spherical trigonometry cuz none of this 'stuff' happens on a flat plane, and to top it all off cuz the one signal you are analyzing is never the only one 'there' so can be affected by another signal (intermod) - how two signal interact and the results.
Let me know when you get your head around all that so we can continue...

[Do I already have my head around all that stuff? Of course, naturally! ... And if you believe that, there's no hope for you at all. All those things really are considerations for antenna comparisons. The only part that isn't 'true' is that I understand it all, I certainly don't. I've been exposed to it! But I've been exposed to a skunk too! I don't plan on ever being exposed to either one again if I can help it.]

Just some 'common' stuff.
How much is reflected from the ionosphere is frequency related. Lower frequencies tend to get 'bent' and reflected back more often than higher frequencies are. Those 'lower' frequencies tend to sort of be divided from those 'higher' frequencies somewhere around 30 - 60 Mhz. (Why 6 meters seems sort of 'odd' in relation to either low/high frequencies.) Those lower freqs that are reflected are not totally reflected, only partially. No idea what that % is, not sure I even want to know. If you think of a signal as being razor sharp when first transmitted, when it get's reflected the first time, it's about as razor sharp as a baseball bat after wards. The second, third, whatever reflection makes it even more 'fuzzy', creates a huge number of multiple reflections because of that 'fuzziness', and therefore 'weaken' each of those reflections.
Under conditions where everything is controlled (yeah, right!), the results of a comparison are 'close enough' for an 'average'/valid comparison. Under conditions where you can't control all that stuff, the comaprison might still be ~sort~ of valid. And that's really okay for the average person. But the 'catch' is that it's only valid for the exact conditions under which the comparison was made. Take it all to a different location and all bets are off. OH BOY, we get to do it again! Why what you may find as a totally worthless antenna in your location may be the absolute bestest performer in another location.
Sort of gives a 'ball-park' estimate a whole new meaning, huh? Also why a salt-shaker is a nice thing to have around sometimes. Am I saying all antenna comparisons are trash? No, I'm not! Just keep that salt handy...
- 'Doc

If I recall I am right about 102" on element and between 100 and 106 on the g/p
radials.I am unable to take pictures right now because of an injury I suffered coming off the roof (BROKEN LEG 3 PLACES) adjusting my FTA antenna dish.But will definitely post some when I get a chance!

Thanks,
Strikesmith

Quote:

Originally Posted by Strikesmith If I recall I am right about 102" on element and between 100 and 106 on the g/p

Well Strikesmith, poor old "Doc just don't get it and has never been able to enlighten anyone with advice from his considerable knowledge---ever since his moma tried so futility to teach him, as a lad, how to wipe his own butt. She would tell him, over and over again and again how to do it, but then go, on and on about how nasty it could be if he got something on his finger, “…ah the harrow of it all what should I do, he kept asking himself.” Is there any wonder that he is a “thingy” and “sorta” kind of guy?

It may be useless for us to continue in our interest as a waste of everyone’s time as we piddle-away on a totally unpredictable exercise in futility, but the antenna I showed you earlier, used 102" whips as radials and a stinger to answer your question.

I built the one in the image below just this morning and put it up to compare with my AstroPlane, which is also up and working. The Marconi, as I call it, is also working fine and performs almost as good as my AstroPlane, even though I know that all my observations and perceptions about what I see and hear are all wrong and are just worthless bits of information that cannot be of any value.

According to the ‘Doc, maybe it is futile for us to waste everyone’s time talking about such things that we sense, feel, and experience in our radio hobby. lol I say keep up with your adventures and your ideas.

What’a think?

Strikesmith,
You have to make allowances for ol'Marconi, it's an age thing. He does mean well, please don't misunderstand! (You also have to be careful of what you say around him, you know? Happened to mention that 'misunderstands' thingy at a ball game once, he spent the next hour looking for that Miss under the stands.)
Sorry to get off topic, but sometimes a little explanation is sort of necessary...
- 'Doc

Like I always say 'Doc "...never pass up on an opportunity, you might not get another chance." Now I don't waste time anymore, I get to the game early and check under the stands first thing.

Strikesmith, here is what I'm working right now comparing my I-10K to my little Marconi 6x with 6 ground plane elements and a 102" whip stinger. Signal Reports will follow soon.

with input from marconi , w5lz , bob85 and a few others i built a 1/4wgp for my base . the hardest part was getting the confidence to try it and not be afraid id kill my radio on the first keyup to check for vswr tuning . mine is just made out of 12 gauge speaker wire using pvc pipe from lowes . each of my sloped ground radials are 108 inches . the vertical element started about 9 ft 3 or 4 inches and after many clippings i got down to under 1.2 across the cb band and called it a day , coulda got a lil lower but my back and knee was really convinced the swr was acceptable and convinced the rest of me it was too , LOL . i didnt measure the finished length but i probally cut about a foot off a lil at a time .

__________________

Come on booty, are you goin' to make us ask you the 'twenty four dollar question' like so many others do when they've built an antenna and make a post about it?

Pictures also help those guys that can only post smiley faces and cast coments.