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How does rain effect antennas
When transmitting what effect does moisture and/or
precipitation have on various kinds of antennas, also what is the effect of rain on say uninsulated ladder line. What is the general effect of moisture on antennas and feed lines as power is increased? Bill |
zeno wrote in message ...
When transmitting what effect does moisture and/or precipitation have on various kinds of antennas, also what is the effect of rain on say uninsulated ladder line. I'm sure it could vary to freq being used, but overall, very little. Rain will not have much effect on ladder line, unless there is a way for water to bridge the gap between wires. You will see increased loss with twin leads, but very little with ladder line that has mostly air between the wires. What is the general effect of moisture on antennas and feed lines as power is increased? Well, again could vary, but overall not a whole lot in general. With my coax fed dipoles, it doesn't matter if it's raining or not up to 1500w. There is no difference in performance. I could see water maybe having more of an effect on say real high freq antennas. UHF, etc.. HF, there is little difference unless you have a problem caused by water. IE: waterlogged coax, twin lead that is wet, etc. MK |
Hi Mark,
Thanks for the response. Good, I won't worry about it. But I do know about coax seal, rubberized electricians tape, and being throrough with my connections. tnx agn. 73 Bill Mark Keith wrote: zeno wrote in message ... When transmitting what effect does moisture and/or precipitation have on various kinds of antennas, also what is the effect of rain on say uninsulated ladder line. I'm sure it could vary to freq being used, but overall, very little. Rain will not have much effect on ladder line, unless there is a way for water to bridge the gap between wires. You will see increased loss with twin leads, but very little with ladder line that has mostly air between the wires. What is the general effect of moisture on antennas and feed lines as power is increased? Well, again could vary, but overall not a whole lot in general. With my coax fed dipoles, it doesn't matter if it's raining or not up to 1500w. There is no difference in performance. I could see water maybe having more of an effect on say real high freq antennas. UHF, etc.. HF, there is little difference unless you have a problem caused by water. IE: waterlogged coax, twin lead that is wet, etc. MK |
Precipitation in general, and snow in particular, can have another effect on
the antenna. And that is static buildup. You can get static voltages large enough to damage sensitive semiconductors, such as MOS transistors. It is usually recommended that you have the antenna either DC grounded or have some type of sparc gap for the static to jump across. Of course, your antennas should be grounded when not in use but not everyone does this. In the winter, don't forget, you can get ice buildup on your antenna and feedline From personal experience---I was a memebe of the radio club at Ohio State (W8LT) many years ago when they were located in the OSU stadium. We had a genuine long wire run from the stadium over to a smoke stack on the power plant it was a few hundred feet long. In the winter when ever we had a dry snow there would be quite a static build up. There was a sparc gap inside the antenna tuner, and you could hear it going snap snap snap as the charge would build up and then arc over. I certainly wouldn't want to get my fingers across the thing under those conditions. -- Jim N8EE to email directly, send to my call sign at arrl dot net "zeno" wrote in message ... When transmitting what effect does moisture and/or precipitation have on various kinds of antennas, also what is the effect of rain on say uninsulated ladder line. What is the general effect of moisture on antennas and feed lines as power is increased? Bill |
Hi Zeno
Some will say it don't affect it all, others will say it will affect it a little bit and other will say it affects it alot. I had several little 1/16th watt neon lights laying around doing nothing. I would toy with them, lining them on dipoles to find the highest area of RF on the dipoles, once found, I would solder these little rascals to the dipole so they wouldn't move in the wind. Besides looking cute, they offered a little bit of help too. When it was raining, they wouldn't lite at all on a couple of antennas, and on others were very dim. This alone tells me that there is some affect of rain on the antennas. But one question has always perplexed me to no end. Why will the light light up if placed on the end of my 10 meter mobile antenna, but not on the end of 10 meter ground plane. It lights up just fine about 19 inches below the top on the ground plane and about 22 inches below the top on a vertical with an underground radial bed. TTUL Gary |
On Tue, 20 Apr 2004 07:35:50 GMT, zeno wrote:
When transmitting what effect does moisture and/or precipitation have on various kinds of antennas, also what is the effect of rain on say uninsulated ladder line. I've heard rain affects balanced line, but I use standard insulated 450 ohm ladderline to feed a dipole, and I can't detect any SWR changes when the line is wet or dry. Bob k5qwg What is the general effect of moisture on antennas and feed lines as power is increased? Bill |
"Gary V. Deutschmann, Sr." wrote in message
... Hi Zeno Some will say it don't affect it all, others will say it will affect it a little bit and other will say it affects it alot. I had several little 1/16th watt neon lights laying around doing nothing. I would toy with them, lining them on dipoles to find the highest area of RF on the dipoles, once found, I would solder these little rascals to the dipole so they wouldn't move in the wind. Besides looking cute, they offered a little bit of help too. When it was raining, they wouldn't lite at all on a couple of antennas, and on others were very dim. This alone tells me that there is some affect of rain on the antennas. But one question has always perplexed me to no end. Why will the light light up if placed on the end of my 10 meter mobile antenna, but not on the end of 10 meter ground plane. It lights up just fine about 19 inches below the top on the ground plane and about 22 inches below the top on a vertical with an underground radial bed. TTUL Gary One question perplexes me - are you so bored that you can't think of anything better to do other than solder neon lights to your antenna??? My God, someone please shoot me if I ever get to that stage!!! ;-) |
Bob Miller wrote:
I've heard rain affects balanced line, but I use standard insulated 450 ohm ladderline to feed a dipole, and I can't detect any SWR changes when the line is wet or dry. Some (biased) experiments have been performed with twinlead laying on a wooden deck wetted by a soapy solution. Moral: Avoid soapy horizontal ladder-line. :-) I use the length of the ladder-line to tune my antenna system to resonance. I have to change the length by up to 2% to compensate for the rain, i.e. rain has a negligible effect on the tuning of my antenna system. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
When I was a kid I remember tuning my antenna with one of those little neon
bulbs soldered to a couple of little loops of wire. One guy would be at the transmitter, the other guy up on a ladder with the bulb. When the bulb was brightest your antenna was tuned....or something like that... Zeno Marty wrote: "Gary V. Deutschmann, Sr." wrote in message ... Hi Zeno Some will say it don't affect it all, others will say it will affect it a little bit and other will say it affects it alot. I had several little 1/16th watt neon lights laying around doing nothing. I would toy with them, lining them on dipoles to find the highest area of RF on the dipoles, once found, I would solder these little rascals to the dipole so they wouldn't move in the wind. Besides looking cute, they offered a little bit of help too. When it was raining, they wouldn't lite at all on a couple of antennas, and on others were very dim. This alone tells me that there is some affect of rain on the antennas. But one question has always perplexed me to no end. Why will the light light up if placed on the end of my 10 meter mobile antenna, but not on the end of 10 meter ground plane. It lights up just fine about 19 inches below the top on the ground plane and about 22 inches below the top on a vertical with an underground radial bed. TTUL Gary One question perplexes me - are you so bored that you can't think of anything better to do other than solder neon lights to your antenna??? My God, someone please shoot me if I ever get to that stage!!! ;-) |
Bill wrote:
"When transmitting what effect does moisture and / or precipitation have on various kinds of antennas---?" I worked off and on for 10 years in a medium wave broadcast station with a 4-tower directional array (separate day and night patterns) fed by open-wire 6-wire skeletal coax. Every half hour we recorded the sampling loop currents associated with each tower and the phase relationships between the towers using an RCA WM-30A phase monitor. Precipitation and fog didn`t amount to a hill of beans in nearly all cases. Currents and phases were nailed in place. Best regards, Richard Harrison, KB5WZI |
"Marty" wrote in message ...
I had several little 1/16th watt neon lights laying around doing nothing. I would toy with them, lining them on dipoles to find the highest area of RF on the dipoles, once found, I would solder these little rascals to the dipole so they wouldn't move in the wind. Besides looking cute, they offered a little bit of help too. When it was raining, they wouldn't lite at all on a couple of antennas, and on others were very dim. This alone tells me that there is some affect of rain on the antennas. But one question has always perplexed me to no end. Why will the light light up if placed on the end of my 10 meter mobile antenna, but not on the end of 10 meter ground plane. It lights up just fine about 19 inches below the top on the ground plane and about 22 inches below the top on a vertical with an underground radial bed. One question perplexes me - are you so bored that you can't think of anything better to do other than solder neon lights to your antenna??? My God, someone please shoot me if I ever get to that stage!!! ;-) Actually, i think this might be an interesting experiment. I would assume the neon lights have a brightness that is proportional to the RMS voltage, and that the areas of brightest neons are high voltage (low current) nodes. One question is how are you hooking them up? On the dipole? S. |
Bill wrote:
"What is the general effect of moisture on antennas and feedlines as power is increased?" I worked for years in a shortwave broadcasting plant where transmitters ranged in power between 3KW and 100 KW. Moisture had little apparent effect on the 600-ohm open-wire feedlines or curtain and rhombic antennas at any power level. We can speculate that wet insulators were slightly conductive when wet due to disolved impurities. Ohm`s law says current and heat are higher at high power. The climate was dry for most of the year but the rainy season was intense resulting in occasional floods. As I recall, transmission line flashovers rarely happened in wet weather but dry was the norm and arcs were infrequent in any case even at 100 KW with 100% high-level modulation. From my mediumwave experience I would say that most antenna system arcing resulted from approaching moisture, not to its arrival. Approaching thunderstorms are often preceded by charged air sweeping across the antenna system. Tower guy segments, separated by insulators, charge until they arc across the insulators with a loud report (Bang!). This triggers ionized paths which short antenna system parts. This overloads the transmitter which removes itself from the air to clear the overload and protect itself. This often repeats rapidly until the storm actually arrives and the rain starts. Best regards, Richard Harrison, KB5WZI |
Hi S
I just wrap the two wire leads around the dipole wire. The lamp lights whether the dipole wire is insulated or not, if you have it in the right place that is. They also let you know if your on the right antenna too! TTUL Gary |
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Hi Slick
There does NOT have to be an electrical connection at all. You can use lamps that have the leads broken off completely and it works just fine. TTUL Gary |
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Hi Slick
Your getting above my head on that one. I know if I move the light back and forth a few inches it will dim and then go out, there are several points along a dipole where the lamp will have high brightness and this is where I put the lamps. I know the CBers used to put a neon lamp on the tip of their mobile antenna's. I first tried it on a 10 meter mobile and it worked fine. But on a ground plane it didn't work, then I started moving the light down the shaft of the antenna and found a spot where it did work just great. Back in the good ole days of the Heathkit Sixer lunchbox, I could put a flourescent lamp against my mobile antenna and it would light up on transmit. I never could get it to do that when I was using the Saturn V halo though. TTUL Gary |
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Hi Slick
Back when I first got into ham radio, I was just a poor widdle kid and had to home brew my first couple of rigs or get some really old Eicocraft or abandoned Heath gear for the shack. My first receiver was a simple HR10B if I have the number right and I had home brewed a simple 40/80 meter single tube transmitter. I saved up my money from working after school and built an HW101, which I still owned up until only a few short years ago. The only SWR meter I had was one I picked up at a swap fest for 5 bucks. I think it was originally made for CBer's but covered all of the HF spectrum, but also could only handle up to around 10 watts. My first antenna's were simple dipoles, and because I could only afford one length of coax I connected all of my antennas spider fashion without a balun (didn't even know what one of those were back then). But fortunately, the old rigs had a lot of tolerance for mismatched loads and high SWRs. Little by little I would get my antennas in tune. I enjoyed CW so much that I spent almost 20 years using nothing but CW on HF, having never once plugged a microphone into my HW101 back then. After I learned to drive, I even ran CW in my car, using a military code key that clipped to my leg with a large clamp designed for that purpose. I wish I still had the abilities I had back when I was a bubble gummer! CW was just like talking to me, I heard the words not the individual letters, never had to write anything down. Then I got sick and was out like a light for over a week, had caught that darn Hong Kong flu virus, which was bad enough, but about a week after that I was hit with Encephalitis which caused a large memory loss and I have had periods of decreasing epileptic seizures ever since. They are now about 8 to 10 years apart and mild, but wipe out small parts of recent memory. After surviving the Encephalitis attack, CW was as strange to me as it would be someone who never ever heard it before. It was a long hard road to learn it all over again, and it gave all of those I normally talked with on CW a chance to get their come uppance by getting even with me by using higher and higher speeds. I never regained my ability to hear the words as plainly as before. A number of years later, long after marriage, kids and eventually buying a home, a mild seizure caused my engineerings skills to deteriorate considerable, but at the same time made learning electronics a snap. Things at work were virtually over my head and I left that engineering companies employ and went to a company where I worked my way into chip level repairs in their electronics division. Everything just came natural to me, almost like I knew it my whole life. There was not a circuit board problem that I couldn't fix. Then after working there for about 4-1/2 years, I got hit with another seizure, this one a little rougher than the last. The boss liked my work and held my position open for me. I went back to work, but wouldn't accept any pay until I could get back into the swing of things. I tied up a station for almost three months and could not grasp anything. Even trying to repair a simple analog power supply was far beyond my capabilities and I just wasn't getting anything back. So I left and got back into something I had done from my youth, and for the rest of my life had stayed away from anything learned beyond the age of 18, as I never forgot things from back then, except the CW from my first sickness. I was working in electronics when I designed the antenna's I placed on my web page, they were good designs and worked great. I could run with the best of them in describing the hows and whys these antennas performed so well for me. But along with my memory loss in electronics, also came my memory loss regarding these antennas, other than I know they worked. I can look at my calculations and formulas and just go duh, having no idea what they mean. It's very frustrating to say the least. Makes one look like a blithering idiot most of the time, especially when you talk to someone you had given excellent advice to years earlier and now you can't even tie a shoelace so to speak! My web pages went unchanged for years because I couldn't remember how to access them or write the changes in .html, had to learn that all over again too! A royal pain. Although you don't hear about it much, there are about 1 in every 10,000 who have the same types of problems I do, and about 1 in every 1,000 who suffer from the same illness, just affected in different ways, like loss of large or small motor skills, temporary deafness, temporary blindness, that lasts for months or in some cases permanently, etc. I have been one of the fortunate ones if you view it in a certain light. I may forget everything, but something else has always seemed to take it's place and be so sharp that it becomes natural to me. The downside is, you have to change jobs every few years. So I decided to work for myself, that way I wouldn't disappoint another employer down the road who came to count on me. I've tried, but I just can come to firing myself, hi hi..... TTUL Gary |
Hi Slick
Well, that must have been interesting to have that sort of ability. Actually, what makes CW hard is trying to learn it at different speeds. CW is entirely different at different speed levels. I guess I should say the SOUND of a word is what is different. When your talking to someone in person, you don't say aich eye bee oh bee, you simply say Hi Bob Low speed CW is like saying aich eye bee oh bee. High speed CW is like saying Hi Bob. A good example of this is listening for someone calling CQ, after you do it long enough, you no longer hear the letters CQ, you hear the SOUND the code makes for those letters and easily recognize a call for CQ, just by the sound of it. A new typist can tell you where every key on the keyboard is! A seasoned typist will have trouble doing this, because the word they are typing goes from their eyes or ears or mind, right through the fingertips to the printed text, it's automatic, they don't stop and think about each letter they are pressing, their fingers just do it automatically. Pick up some code tapes that run at 20 words per minute and you no longer hear the individual letters, you hear words. Good high speed code tapes work by using only a single word for several itterations, than add a new word for several itterations, then combine a few words into a sentence. Pretty soon you HEAR only the words and not the individual letters. The only time you slow your sending speed is when sending your callsign or an unknown unfamiliar word, like an obscure town name. In essence, you hear the PHONICS of the sound of the code that make words, thus large words are as simple to understand as short words. So, did you get your case from a virus? Yes, it was the result of high fever associated with the Hong Kong Flu (a virus). Well, from the Tao, we get, "Loss can be a Gain", and in your case it might be that you gained by losing the boss! I honestly have! And really do consider myself fortunate in many ways. From the outside looking in, it appears I have suffered some great losses and had to start over many times during my life. Even most recently, what appears as a serious tragedy to many, has actually been the best blessing of my life. I won't get into it unless you really want to hear about it. Suffice it to say, I dropped out of the 40 hour rat race and 100k a year, to a position of no debt and more disposable income and more time to enjoy time with my family. And NO I don't get any handouts! I work to earn my living! Just not nearly as many hours and for much less money. But I disposed of my debts by selling everything I owned and paying it all off. What I used to pay in interest charges, I now use for entertainment and time off. TTUL Gary |
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Clean gentle rain water hardly affects anything if its well made. And
anyway it doesn't rain all the time. |
Dr. Slick wrote:
God, it's nice to be your own boss, ain't it? When Intel stock hit 100, I just couldn't resist selling those golden handcuffs and riding off into the sunset on my new Harley. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Hi Slick
Sure Is!!!!! I've been self-employed now for about 25 years, trouble is the first 20 of those I only exchanged one predictible boss for about 100 very unpredictable ones, my customers, hi hi. Then I did away with customers until after the fact. This meant I could basically do it my way, when I wanted to, and when finished then find a customer for it. I think now I have the best of both worlds. I don't have to deal with customers at all. I have one mfgr. rep. who handles all of the distribution for me. Even had him scheduled to place orders only once per month for awhile, then as he grew I boosted that to ordering only once every other month. I now run two businesses in similar fashion on alternating months and am working on a third that will be totally out of house, meaning all I will have to do is make a single phone call each time the mfgr. rep. orders or I could have him place the order direct and not bother me at all with it, which is the way I may go with it too. But it does get boring not having anything to do, so I'm doing hard labor, hi hi. Cleaning out the overgrown woods on a hillside! Darn chiggers! TTUL Gary |
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Cecil Moore wrote in message ...
Dr. Slick wrote: God, it's nice to be your own boss, ain't it? When Intel stock hit 100, I just couldn't resist selling those golden handcuffs and riding off into the sunset on my new Harley. :-) Ha! Golden handcuffs instead of Golden parachutes? Great. I've never heard of a job describe like that, but it's quite appropriate, like a 5-star luxury prison cell... Slick |
Dr. Slick wrote:
Ha! Golden handcuffs instead of Golden parachutes? Great. I've never heard of a job describe like that, but it's quite appropriate, like a 5-star luxury prison cell... Exactly, companies handed out so many stock options that matured sometime in the future that nobody could afford to quit the company. That was in the 90's of course when tech stocks knew no bounds. Don't know how it is working in the present day. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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