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 <[email protected]> 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 <[email protected]> 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 <[email protected]> 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 <[email protected]> > >> 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 <[email protected]> > >> 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" <[email protected]> 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 > _________________ Topband Reflector
