Hi Mike,
No problem. I thought I ... nevermind, I guess I need to go back and read
everything again more carefully. :-) But later. I'm listening on 160m
right now.
No offense taken, my friend.
On Fri, Sep 6, 2013 at 8:45 PM, Mike Armstrong <armstrmj@aol.com> wrote:
> Mike, you are answering the wrong question. Guy didn't understand the
> question at all. I KNOW that sea water is a better ground than dirt......
> The comparison I was ALWAYS talking about had NOTHING AT ALL to do with
> LOCATION! NOTHING! The comparison was a quarter wave vertical compared to
> a 5/8ths wave vertical IN THE EXACT SAME LOCATION...... Sorry Mike, I am
> taking it out on you and it wasn't your fault. People are responding who
> didn't actually read what I wrote, then they comment..... and they YOU
> commented on their comment which had the wrong premise to begin with..... I
> say again, the comparison had nothing to do with the actual location, but
> rather two different vertical types in the exact same place..... Well, ok,
> a few yards apart, but with the same number of radials and the same
> seawater location (Iroquois Point Military Housing on Oahu). THe words
> RURAL or DIRT were used nowhere in my original email.
>
> What intrigued me was that I had such a great experience with a 5/8 wave
> vertical over a 1/4 wave vertical AT THE SAME LOCATION..... and on 20
> meters. Tom commented that 5/8 waves were basically garbage on 160 and I
> would like to know why..... IF he knew or had a clue as to the why. Then
> Guy started talking about seawater vs rural dirt and off the entire thread
> goes in the wrong direction...... a direction that indicated he was reading
> stuff into my post that just wasn't there. It is exasperating in the
> extreme to have that happen, then others like yourself are misdirected by
> their misdirection because you read theirs instead of mine..... Not knowing
> that they actually didn't read what I wrote. NOT YOUR FAULT, but
> exasperating because I feel compelled to answer you because you were kind
> enough to provide some details, but details to an issue that I wouldn't
> have mentioned because I KNOW that salt water is better than dirt..... I've
> lived in Hawaii, within yards of the ocean and then Arizona, which probably
> has the world's least conductive dirt on the entire planet.
>
> My desire IS STILL to have someone who might know give me a clue as to why
> the 5/8 doesn't work well on 160 when it works so fabulously well on 20
> meters (for one band). I use one out here in AZ on 20, too. It has alot
> of straight copper radials underneath it (60 half-wave long radials to be
> precise) and it works as well here, anecdotally speaking, as it did in
> Hawaii..... Well, not "quite" as good, but darned close if you take into
> account the difference in solar activity, too. When I was on Hawaii, the
> spots were a whole lot better, even tho they were decreasing, than they are
> today at the current "peak." If "peak" is the right word for this one.....
> he he he. But I digress.... I find it interesting that an antenna that
> appears to work so well on 20 as a ground mounted vertical, can be so bad
> on 160..... I would like to know why.....
>
> Thanks for responding Mike. I am sure you will get the gist of what I was
> talking about, now. No insults intended towards anyone, but this does
> provide a good example of what happens when folks don't read the entire
> email someone sends and then comment on it....... Then others, who have no
> idea that the person responding didn't read the email all the way thru or
> thoroughly, respond to the responder...... and away she goes..... LOL. I
> was starting to get a little wound around the axle, but now it is just
> funny. Between you and me (ha ha ha) I am not going to respond to anything
> else concerning my email unless someone wants to discuss the question I
> actually, really and truly had..... LOL.
>
> Speaking of which, other than the possibility that a 5/8ths wave vertical
> lays down a very low angle radiation and it is "too low" for 160 (although,
> I have to admit that for DX work, that is a hard pill to swallow..... but I
> am NOT an expert on 160, which is why I read the forum comments here in the
> first place :) :) Like I said, when I replaced the 1/4 wave with the 5/8
> wave ground mounted vertical (20 meters only), the unsolicited comments
> concerning my signal were universally positive. I was one of the early
> WINLINK stations and my station being in Hawaii at the time was used by
> MANY, MANY sailboat guys out in the Pacific and, particularly, the Western
> Pacific. Many of the guys who used my system were former or retired
> military having a ball sailing the ocean blue...... Anyway, I needed a
> good, solid performer that, by necessity, had to be omnidirectional in
> nature. So I tried the 5/8ths and batta-bing, batta-boom I start getting
> UNSOLICITED reports in my emails that say something to the effect, "what
> did you do? You are definitely stronger.... in fact, you are downright LOUD
> now." That kind of report. Again, they didn't have a clue I had recently
> changed my winlink dedicated system antenna, but all of a sudden I am
> louder than they are used to hearing me. The only difference was a 5/8
> wave radiator as opposed to a 1/4 wave radiator over the same ground.......
> I then ran some test with some of my friends floating around out towards
> the Philippines and they confirmed, via an a/b test that the 5/8 wave was
> louder. I switched which one was "A" and which one was "B" randomly
> throughout the tests and not once did any of them pick the 1/4 as the
> better antenna. SOOOOOOOOOO, looks like I found a winner for my 20 meter
> winlink node and that antenna is definitely a go-to when I need a solid,
> omni on 20 meters. I am going to turn my station into a winlink node, once
> again, here shortly because my setup, which includes a 5/8 on 20 meters
> over 60 copper radials on TOP of AZ DIRT, seems to work almost as well as
> it did on Hawaii back in the day (all things considered, like the fact that
> this solar cycle blows chunks).
>
> Mike, I am sorry this turned into a book, but maybe now you know the whys
> and wherefores ..... as well as why it still interests me. I would have
> never even thought that a 5/8ths wave wouldn't work well on 160 until Tom
> said something to that effect..... which, due to my experience with that
> particular vertical antenna, made me say, " HUH?" LOL LOL. If you have any
> input on the possible WHY of that statement from Tom, I am all ears..... :)
>
> Mike AB7ZU
>
> P.S. I hope nobody was insulted by my little diatribe. It wasn't intended
> to insult, but just to remind folks that WE really need to read and try to
> fully digest what someone says (ALL OF IT) before we respond and possibly
> really confuse the entire thread. I include MYSELF in that statement for
> sure and certain, since I have definitely done the very same thing in the
> past. Not here, I don't think, but certainly in other ways and on other
> days..... :) :)
>
>
>
> Kuhi no ka lima, hele no ka maka
>
> On Sep 6, 2013, at 17:34, Mike Waters <mikewate@gmail.com> wrote:
>
> > Like Tom said earlier, it's all about ground loss. Near the sea, a 1/2 or
> > 5/8 wave vertical may perform very differently than a duplicate antenna a
> > long way from the sea. The near-field and far-field losses at the lower
> > angles would be much lower.
> >
> > 73, Mike
> > www.w0btu.com
> >
> >
> > On Fri, Sep 6, 2013 at 7:04 PM, Bob K6UJ <k6uj@pacbell.net> wrote:
> >
> >> Mike,
> >>
> >> Tom, W8JI has a comparison between 1/4 wave and 5/8 wave vertical
> mobile
> >> antennas here: http://www.w8ji.com/VHF%20mobile%20vertical.htm
> >> He is comparing mobile antennas but it looks like the 5/8 wave can be 2
> db
> >> better than the 1/4 wave.
> >> Looking at the radiation angle graphs it shows the 5/8 has more gain at
> >> lower radiation angles in particular.
> >> If you were doing your comparison on long haul contacts it makes sense
> >> that the 5/8 would do better.
> >>
> >> Bob
> >> K6UJ
> >>
> >>
> >>
> >> On Sep 6, 2013, at 4:35 PM, Mike Armstrong wrote:
> >>
> >>> Guy, you aren't reading my emails...... because that question is not
> >> appropriate to the conversation. I am NOT, I repeat NOT talking the
> >> difference between LOCATIONS, but the difference between ANTENNAS AT THE
> >> SAME LOCATION! I am NOT talking about RURAL ANYTHING. That location
> being
> >> on Gannet Avenue across from the Marina that was LITERALLY across the
> >> street from my house.
> >>>
> >>> I say again, READ MY EMAIL as your question has absolutely NOTHING to
> do
> >> with the conversation. The fact that you sent the same email to me
> after I
> >> answered you tells me that you are not reading what I wrote. I am not
> >> being insulting, but if you don't read ALL of what I wrote, you cannot
> >> possibly ask a valid question or make any statements about its content.
> If
> >> you read it, you would know that I am not saying ANYTHING about location
> >> changes or differences. OF COURSE a sea water location is better than a
> >> rural location. THAT fact has nothing to do with the comparisons I am
> >> making or asking Tom to discuss. Sorry for the repetition, but I want
> to
> >> make sure that you will see that, even if you don't read this email
> >> entirely. Again, no insult intended, but it is tiring trying to respond
> to
> >> someone who isn't reading ALL of what I wrote and jumping to incorrect
> >> conclusions as a result. I WILL tell you the address, if you still
> want to
> >> know, after you have read and responded
> >> to
> >>> the content of this email specifically.
> >>>
> >>> Mike AB7ZU
> >>>
> >>> Kuhi no ka lima, hele no ka maka
> >>>
> >>> On Sep 6, 2013, at 13:38, Guy Olinger K2AV <olinger@bellsouth.net>
> >> wrote:
> >>>
> >>>> Mike, could you kindly supply the address on Iroquois Point? If it's
> in
> >>>> the area I'm looking at with Google Earth, the answer why the
> >> difference is
> >>>> pretty plain, and points to why such a difference vs. a 160m vertical
> on
> >>>> rural terra firma.
> >>>>
> >>>> 73, Guy.
> >>>>
> >>>>
> >>>> On Fri, Sep 6, 2013 at 1:30 PM, Mike Armstrong <armstrmj@aol.com>
> >> wrote:
> >>>>
> >>>>> Oh, I didn't address one comment you made, Tom...... 5/8ths are dogs
> on
> >>>>> 160? Really? That is odd in the extreme to me. I had incredible
> >> success
> >>>>> with a ground mounted 5/8 on 20 meters while I was stationed in
> >> Hawaii. I
> >>>>> was rather space limited, so I could only go up and a tower mounted
> >> beam
> >>>>> was a "no fly zone" in that particular situation. So, I decided to
> >> try the
> >>>>> 5/8ths wave vertical and its performance was nothing short of
> >> spectacular
> >>>>> when compared to a 1/4 under the same circumstances. Not to malign
> the
> >>>>> simple 1/4 wave, but the 5/8ths performance improvement went way
> beyond
> >>>>> what I would have expected...... and my expectations were certainly
> >>>>> reasonable. My thinking was that lifting the major current node a
> bit
> >>>>> above ground would probably be an improvement and, to my surprise,
> >> that was
> >>>>> an understatement in the extreme.
> >>>>>
> >>>>> I wouldn't want to overblow the results, but I simply couldn't
> believe
> >> how
> >>>>> well the antenna performed on 20. To be sure, I was on Oahu out in
> >>>>> Iroquois Point housing, which is well situated with regard to the sea
> >> (you
> >>>>> are basically ON the water in almost all directions). Additionally,
> I
> >> had
> >>>>> 60 radials underneath the thing, spread evenly around the base (in
> >> straight
> >>>>> lines, no bending). So it was definitely an ideal vertical location.
> >> But
> >>>>> the difference between it and the quarter wave was what truly
> >> surprised me
> >>>>> (with all else being the same.... sea water location, number and
> >> length of
> >>>>> radials, etc). To hear that it doesn't translate to 160 is really a
> >>>>> surprise to me...... Tell me more, assuming you did any kind of study
> >> into
> >>>>> why it didn't seem to work well. I am as interested in why something
> >>>>> DIDN'T work as I am in why it does..... If for no other reason than
> to
> >> save
> >>>>> a few bucks and alot of time.... LOL
> >>>>>
> >>>>> Mike AB7ZU
> >>>>>
> >>>>> Kuhi no ka lima, hele no ka maka
> >>>>>
> >>>>> On Sep 6, 2013, at 9:25, "Tom W8JI" <w8ji@w8ji.com> wrote:
> >>>>>
> >>>>>>> Fully understood. I wasn't referring to the usual collinear
> antennas
> >>>>> sold by "comet" or anything of that nature. I am referring to the
> >> stacking
> >>>>> arrangements used for ops like moonbounce, etc. As far as the design
> >>>>> theory (and practical application) goes, I have a reasonable amount
> of
> >>>>> schooling and experience (been active since 1966..... he he he).
> Just
> >> so
> >>>>> you realize I am not referring to the often (always?) false gain
> claims
> >>>>> made by manufacturers for their antenna designs.
> >>>>>>
> >>>>>> ........but this is verticals, and not a narrow BW like a long Yagi.
> >> The
> >>>>> narrower the pattern of a cell in the stack, the wider minimum useful
> >>>>> stacking distance becomes.
> >>>>>>
> >>>>>> Also, for 160, antennas are near earth. Earth spoils everything. A
> 160
> >>>>> antenna at 260 feet is like a two meter antenna at 3.25 feet above
> >> ground.
> >>>>>>
> >>>>>>
> >>>>>>> All I was saying was, "yes, it is possible and is done" when
> speaking
> >>>>> to vertical stacking. As far as stacking what we would call "ground
> >> plane"
> >>>>> antennas (quarter wave vertical element against elevated radials),
> the
> >> only
> >>>>> example I have seen with any regularity is done aboard some Naval
> >> vessels
> >>>>> (stacked/phased, if you will, horizontally on a yard arm). I "think"
> I
> >> have
> >>>>> seen the same thing at airports, but I cannot tell for certain that
> >> they
> >>>>> are phased arrays or just happen to "look" like they are related.
> >>>>> Understand that in all cases to which I refer, including my own, I am
> >>>>> speaking of phased arrays, which I believe is what we are talking
> >> about as
> >>>>> well. I may have misinterpreted the question to some degree.
> >>>>>>
> >>>>>> This is 160. The distance ratio for the same behavior on two meters
> is
> >>>>> 80:1. If we look at:
> >> http://www.w8ji.com/stacking_broadside_collinear.htm
> >>>>>>
> >>>>>> we see **freespace** short dipole stacking distances, between
> current
> >>>>> maximums, is 0.35 WL for 1 dB stacking gain. This is for freespace.
> >> That
> >>>>> means the current maximums have to be .35*160 = 56 meters apart
> **if**
> >> the
> >>>>> elements are in freespace. They have to be even further apart if near
> >>>>> earth, because the earth reflection already compresses the vertical
> >>>>> pattern. I'd guess, for 1 dB stacking gain over a ground mounted
> >> vertical
> >>>>> (ignoring ground losses), we could move the lower current maximum to
> >> about
> >>>>> 50 meters above earth and eliminate the upper element. That would
> >> pretty
> >>>>> much be a vertical dipole. If we wanted to get 2-3 dB gain, we'd
> >> probably
> >>>>> need 300 feet of height and an inverted groundplane at the top.
> >>>>>>
> >>>>>> For 160, is it is a useless endeavor at normal heights.
> >>>>>>
> >>>>>> Making matters worse, 5/8th wave verticals are dogs on 160. Been
> >> there,
> >>>>> done that, used them. A 1/4 wave vertical, or something up to maybe
> 200
> >>>>> feet, is actually better. They have never worked well here, they
> never
> >>>>> worked when I used broadcast towers, and when W8LT used them in 160
> >>>>> contests they were also pretty weak.
> >>>>>>
> >>>>>> The whole thing is a waste of time on 160. Even if someone could
> run a
> >>>>> vertical collinear with useful gain, it would just kill their signal
> by
> >>>>> focusing it at too low an angle for 160, while nulling more useful
> >> angles.
> >>>>>>
> >>>>>> 73 Tom
> >>>>> _________________
> >>>>> Topband Reflector
> >>>> _________________
> >>>> Topband Reflector
> >>> _________________
> >>> Topband Reflector
> >>
> >> _________________
> >> Topband Reflector
> > _________________
> > Topband Reflector
>
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