|
My vertical blew down!!!
Hi,
It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire |
My vertical blew down!!!
It begs the question, what was it made of? It must have been very thin metal
to blow apart only 16 feet, guyed by ropes. Please enlighten us. wrote in message oups.com... Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire |
My vertical blew down!!!
Ground system:
5 foot of 1 inch diameter galvanized iron pipe, halfway stuck in ground with concrete. 1 inch diameter galvanized coupler 5 foot of 1 inch diameter galvanized pipe 1 inch to 3/4 inch copper reducer 1 foot of 3/4 inch copper pipe 4 tees: 3/4 inch thru vs 1/2 inch out, soldered lengthwise along copper pipe. an 8 foot length of 1/2 inch copper pipe soldered into each tee tees are reinforced above and below radials with a hose clamp coax shield connected to top of copper pipe Radiator: 10 feet of 3/4 inch diameter copper pipe 9 foot carbon fiber fishing rod, handle epoxied and inserted into pipe a wire is attached to copper pipe and run up to end of rod. Hot end of coax connected to bottom of copper pipe Ground system and Radiator are connected in-line with a PVC twist shaft coupler designed for 3/4 inch pipe, weather sealed with epoxy. A gap of 1 inch between pipes inside the coupler is filled with styrofoam to prevent contact. Rope guys are econnected to the top part of the shaft coupler, as the middle of the shaft coupler is predicted to be weakest point. Sure enough, a continuous wind in excess of 60 mph vibrated the shaft coupler into 2 pieces despite the guys, the radiator then collided with a radial, knocking a radial out of alignment and ripping apart a hose clamp. I suspect the wind is going to finish the job overnight. Sigh, The Eternal Squire |
My vertical blew down!!!
dude it's 60-100 mph wind! You're gonna have to shell out bucks to make
anything that can stand up to that for any length of time. |
My vertical blew down!!!
wrote in message oups.com... Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire I use a fishing rod with a wire centre conductor for 40 metres band (33`without guys), with a 5` mounting pole buried in the ground ....you ought to see that mother bend ...... hasn`t fallen or blown down yet!!! ;-) Lee.......G6ZSG..... |
My vertical blew down!!!
|
My vertical blew down!!!
wrote:
Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Same kind of location here, wide open to the Irish Sea.... but that wasn't a big antenna, and with the guys it certainly should have stayed up. You're missing something here. Typical ham antenna structures are a mixture of over-design and weak spots, so maybe you should look at the wreckage in more detail and try to learn something from it. OK, I just read your second posting and pulled this back from the outbox. From the top downwards... * Fishing rod good. Carbon fibre not good (possibility of losses and detuning compared with plain fibreglass; definite loss of money compared with plain fg). * Copper pipe not good in these long lengths. Ask yourself why everyone else uses aluminium. * PVC pipe coupler not good... well, that you know. * Again, copper pipes not good for radials. Copper pipe tees not good for supports. If the top part hadn't fallen down, those pipe tees would probably have been next to go. * 3/4-in copper for your main support mast is a big mistake. The heavy radials flopping up and down create a huge leverage at this point, so that copper will be rapidly work-hardening and well on its way to breaking (may well have done so by your morning). * In your wind conditions, 1-in galvanized pipe is way too small for the lower part of your mast. The only thing that kept it from snapping is that something else broke first. * Were your guys helping to reduce the bending forces at the point where the coupling snapped... or helping to concentrate them? In your particular case, I'd bet the latter. The big lesson is that the construction of a copper J-pole for 2m will not scale up to 20m wavelengths... basically because copper tubing is a poor structural material, and as the model-makers say, "You can't scale Nature." When you increase the scale by 10x, you have to use different structural materials and techniques. Again, ask yourself why everyone else uses larger tubing for masts; uses aluminium, not copper; and doesn't use small, soft plastic plumbing fittings. Have a look at HF antenna construction in the antenna handbooks and catalogues, and do what they do... because there's a reason for it. Does anyone know of a decent commercial design for less than $1000 for Hang on now - that would be spending money to *avoid* learning something. a free standing 30 to 40 foot support that can take this darn wind??? One option that's surviving very strong winds here is a tapering fibreglass pole. I'm using a Spiderbeam telescopic pole that is almost 40ft high and strongly made: www.spiderbeam.net/english/pole.php The pole is tied to a very solid clothes-line post at about 7ft, and also guyed at about the 30ft level to prevent the worst of the swaying. In very strong winds it bends into an alarming S-shape, but by the nature of fibreglass it also springs back again. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
My vertical blew down!!!
I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength
radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! It decided to blow it down so you could rebuild it with the proper length radials...:( 1/8 radials won't work too well. Why would you use those? They are fairly useless on an elevated ground plane. The decoupling of the feedline will be poor, and probably lots of rf in the shack. Needs 1/4 wave radials to work correctly. As far as the wind, you need to build a little stouter... Normally, a short 16 ft radiator should be easy to keep up, even with 60 mph winds. Shouldn't fall down if it was guyed. My 40 m ground plane was 32 ft tall, mounted at 36 ft. Nearly 70 ft tall at the top. Only my mast was guyed. No guys were used on the radiator. I used a telescoping metal mast which shrunk down to a very thin size as it neared the top. Was quite flexible. In heavy storms, it would nearly blow sideways, but it never hurt it, and it always popped back up straight after the wind left. That particular antenna cost nothing..Made from an old butchered up 5/8 wave CB antenna as the base radiator, and then extended with extra tubing. Was looking at your 2nd post, and notice the details. Not exactly the recipe for a solid antenna...You would be better off using an old butchered CB antenna, etc. The cushcraft AR-10 makes a good platform for verticals also. It's a 16-18 ft 1/2 wave antenna for 10m. If you use only the radiator, and redesign the feed, thats a decent quicky 20m 1/4 wave vertical. The old heavy duty 5/8 CB antennas are good to use also. They have heavy duty bases that are often reinforced. Thats what I use for my tall 40m antenna, and never had a problem, but I did strengthen by adding extra tubing , inside the tubing. IE: double wall... Copper is pretty soft, and shouldn't be used for anything that needs real strength. MK |
My vertical blew down!!!
Actually, pure aluminium is even softer and far more ductile than
copper and is useless as a construction material. But some grades of copper/aluminium alloy, known in the UK as Duraluminum or just Dural, have properties approaching carbon steel and are corrosion resistant. Light in weight. Easily machined and extruded. Maintain a good appearance. High electrical conductivity. More expensive than steel. They are used, for example, for ladders and scaffold poles. When used for tubular rigid dipoles and antenna masts they collapse under high winds only because the wall thickness is too thin. Commonly used for radio chassis and sheet metal roofs. But NOT pure aluminium, just a few percent of copper. ---- Reg. "Cecil Moore" wrote in message . com... wrote: It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! I use 2x(2"x4"s) fastened together for a 4"x4" support and 1/4WL wire radials as ground-plane/guy-wires. The vertical section is assembled from 6' telescoping aluminum sections following the beam element design guidelines in the ARRL Antenna Book. The top 8.5' is a stainless steel CB whip. It has withstood wind gusts of about 100 mph. As others have said, copper is a poor choice for a 20m vertical. -- 73, Cecil http://www.qsl.net/w5dxp |
My vertical blew down!!!
Reg Edwards wrote:
But NOT pure aluminium, just a few percent of copper. Next time I'll have to remember what a purist you are, Reg. I'll specify Aluminum 6063-T832 or some such. -- 73, Cecil http://www.qsl.net/w5dxp |
My vertical blew down!!!
Visit a farm supply house and see what they have for aluminum tubing...the
stuff they use for making racks for trucks and pickups. wrote in message oups.com... Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire |
My vertical blew down!!!
The pipe thread area is a point of weakness and the overlap is way to short
to provide any strength. A better alternative is aluminum tubing with .058 wall thickness. This allows decending sizes to fit with in one another. For example a 1" 6061 T6 10 foot long has an inside diameter of .884 and a 10 foot section of 7/8" (.875) will slide right into it. This would allow an overlap of almost 4 feet providing all the strength you need. Good luck on your next installation. wrote in message oups.com... Ground system: 5 foot of 1 inch diameter galvanized iron pipe, halfway stuck in ground with concrete. 1 inch diameter galvanized coupler 5 foot of 1 inch diameter galvanized pipe 1 inch to 3/4 inch copper reducer 1 foot of 3/4 inch copper pipe 4 tees: 3/4 inch thru vs 1/2 inch out, soldered lengthwise along copper pipe. an 8 foot length of 1/2 inch copper pipe soldered into each tee tees are reinforced above and below radials with a hose clamp coax shield connected to top of copper pipe Radiator: 10 feet of 3/4 inch diameter copper pipe 9 foot carbon fiber fishing rod, handle epoxied and inserted into pipe a wire is attached to copper pipe and run up to end of rod. Hot end of coax connected to bottom of copper pipe Ground system and Radiator are connected in-line with a PVC twist shaft coupler designed for 3/4 inch pipe, weather sealed with epoxy. A gap of 1 inch between pipes inside the coupler is filled with styrofoam to prevent contact. Rope guys are econnected to the top part of the shaft coupler, as the middle of the shaft coupler is predicted to be weakest point. Sure enough, a continuous wind in excess of 60 mph vibrated the shaft coupler into 2 pieces despite the guys, the radiator then collided with a radial, knocking a radial out of alignment and ripping apart a hose clamp. I suspect the wind is going to finish the job overnight. Sigh, The Eternal Squire |
My vertical blew down!!!
Try these guys http://www.valcom.ca/welcome.html they make antennas for
coastal coast guard shore stations and military ship antennas I had one of the 74 foot shore/vessal antennas it was a 74 feet high with a capasative cap and worked like a hot dam. Mind you I got mine free for the taking at a Canadian Coast Guard station that had replaced the antennas with something bigger. The Valcombs are used on board ships all over the world and on shore, I got mine where the wind was blowing on average about the same as what you have 90% of the time, a typical shore station locations. The one I had up weighed 700 lbs and required approx. 6 yard of cement and it never even as much as moved when the wind blew. Sold mine to an amateur in SD aka tornado alley and last I heard he lost his barn but the antenna surived without even as much as a scratch. Oh by the way it has a really low angle of radiation and worked fantastic for DX, best antenna I've ever used, next to a rombic on the Artic Circle, aka DEW LINE. 73...de ve7agw Al wrote in message oups.com... Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire |
My vertical blew down!!!
All,
Thanks so much for getting back on this... I am located about 50 miles west of Gallup, NM. I am in a trailer park so I do not have a very large lot. Also while my super is a nice person, amything large enough to seriously ding a trailer if it fell would not be not okay with him. My wife also wants to put a storage shed next to the trailer fairly well adjacent to where I mounted my first pipe into concrete. That limits my choices further. My YF is generous enough to allow me to keep trying with this antenna, but she is already concerned that I put $300 into it ($175 parts and concrete, $50 tools, $75 to hire someone who speaks propane torch) and thinks that I should leave the design and installation to a professional, hence my question about decent mounting for less than $1000. For purposes of discussion the dimension limits to be about 25 to 35 foot vertical, and about 8 foot radius for mounted radials. I am allowed to create ground counterpoises up to 40 feet long as long as they snake into the back lot. Severe sway is not allowed as it could spank the trailer. One thing I have noticed is that street lamps and telephone poles are unguyed but have no problem with this wind. Unfortunately, I am not close enough to either of them to use them for a mounting. (I cannot move, I am committed to staying. I got laid off by my company in mid-september and we moved to a place where my wife could use her new master's degree in education... and we have to stay in this trailer right next to her school as a condition of her employment... it is, fortunately, low rent forced housing). Questions: 1) Since I have an 8 foot limit for radials, could I have 1/4 wavelength helical radials for 40m that could fit into an 8 foot length? 1a) Could I do the same helical trick for the radiator as well? 2) My base 1 inch diameter galvanized pipe is presently 2 1/2 foot into a 2 1/2 foot cube concrete filled hole with 2 1/2 foot exposed. What could I screw in it that would not need guying, and would not bend nor sway in 100 mph wind, and how high could I make that? 3) If I run up a metal pipe to 20 foot and then an insulated wire from the dirt to the top alongside the pipe as my radiator, what effect will the pipe have on the radiating wire? Thanks again, The Eternal Squire |
My vertical blew down!!!
wrote: 3) If I run up a metal pipe to 20 foot and then an insulated wire from the dirt to the top alongside the pipe as my radiator, what effect will the pipe have on the radiating wire? *Install the pipe. *Build a 16-17 foot tapered radiator made from telescoping lengths of 6061-T6 aluminum tubing. See the Texas Towers site for the tubing. E-mail me about doing the design of the radiator, I'm equipped to do the FEA stress analysis. *Build an aluminum adapter plate to attach the radiator to the pipe. See any "how to" type ham antenna book which includes the construction of yagis. Use a pair of stainless steel u-bolts to attach the adapter plate to the pipe. Use a pair of insulated clamps to attach the radiator to the adapter plate. These are available from DXengineering. http://www.dxengineering.com/Section...&DeptID=21#Top *Run ONE 16-17 foot wire to the the adapter plate but do not ground it. Instead attach it the braid of the coax. Attach the radiator to the center conductor of the coax. Pull the "radial wire" as far away from the trailer as possible in some direction or another. This arrangement would give you a "sorta" inverted L or vertical dipole type antenna instead of a ground plane. Thanks again, The Eternal Squire w3rv |
My vertical blew down!!!
|
My vertical blew down!!!
I have no trees, streelamps, telephone poles, or anything higher than a
7 foot trailer. That was why I was considering a vertical. For practical purposes anything higher than 40 feet is forbidden and 25 foot is as high as I practically dare do. From what I understand, dipoles are not effective below 1/2 wavelength above the dirt, but verticals can work well fairly close to the dirt if they have to. From what I hear inverted vees are slightly better than dipoles but slightly worse than verticals at low altitude. My wife really doesn't care about money as much as she cares about waste. If I can make my setup working with the stuff I already bought then great... At this point I am considering just throwing in the towel and raising a 20 foot iron pipe to mount a 20 meter inverted vee... sigh. 20m is my favorite band, followed by 40 then 30. The Eternal Squire |
My vertical blew down!!!
I have one problem... I can only get stuff from Home Depot, about 50
miles away. The Eternal Squire |
My vertical blew down!!!
|
My vertical blew down!!!
|
My vertical blew down!!!
|
My vertical blew down!!!
Excuse me very much, but isn't shipping for exotic alloy pipe going to
be more expensive than the pipe itself? That's not negative, that's practical! The Eternal Squire |
My vertical blew down!!!
wrote:
Excuse me very much, but isn't shipping for exotic alloy pipe going to be more expensive than the pipe itself? It's not "pipe", it's thin-walled very light weight high-strength aluminum TUBING. which is about as "exotic" as CW in ham circles. Don't ask us what the shipping costs would be, push back yer keyboard and dial Texas towers @ (800) 272-3467 and ask them. As to your problem with hundred-mile round trips to your nearest Home Despot sto I have two of 'em 15 +/- minutes from here and except for some occasional stainless nuts, bolts and cheap wire they're useless as far as decent sources of antenna materials go. The Mother of All REAL Hardware Stores is McMaster-Carr. 3,000 + page of industrial-quality bits and pieces which make great antenna parts only a phone call away. They have staineless u-bolts on top of stainless u-bolts, aluninum stock for adapter plates, all of it . . http://www.mcmaster.com/ (330) 342-6100 for help with finding what you want if their website catalog comes up overwhelming. If you're averse to online purchasing that's OK, order all your antenna "stuff" by telephone, then sit on yer butt and wait to have it dropped on you by UPS or FedEx within a couple days at most. Ditto DXengineering: (800)-777-0703 That's not negative, that's practical! You have problem with your priorities and what's up out here in practical ham antenna realities. The Eternal Squire w3rv |
My vertical blew down!!!
My suggestion would be the following:
Cut that buried 1" pipe about a foot over the ground, to serve as a ground support for your new antenna. Get a heavier steel pipe (ca 1"3/4 - 2") that will fit over the 1" pipe, and perhaps 10 foot long. Get a cheap fiberglass (not carbon) fishing rod ca 18 feet long, (1/4 wave on 20m) Tape a 1/4 wire radiator to the fishing rod, and feed with coax at bottom of rod. Attach fishing rod securely to the top of your new mast pipe. Rise the pipe and fishing rod assembly vertically and guy at the point where the fishing rod is attached. Now you can run elevated wire radials along the guy ropes, and you should probably also ground the coax shield to the mast pipe at the feed point. Enjoy! 73 de Hans, SM3PXG wrote: Ground system: 5 foot of 1 inch diameter galvanized iron pipe, halfway stuck in ground with concrete. 9 foot carbon fiber fishing rod, handle epoxied and inserted into pipe a wire is attached to copper pipe and run up to end of rod. Hot end of coax connected to bottom of copper pipe Rope guys are econnected to the top part of the shaft coupler, as the middle of the shaft coupler is predicted to be weakest point. Sigh, The Eternal Squire |
My vertical blew down!!!
Now THAT's a practical idea...
Thanks! The Eternal Squire |
My vertical blew down!!!
Hi,
Given the circumstances you have.. I would give some thought about putting up a vertically mounted Small Transmitting loop such as the MFJ. Will it work as good as a Vertical? , not one that has a good radial system under it and a clear shout at the horizon.. but it sounds to me like it might be just right for your needs.. Give them a Look I built one here and used it for a couple of years mounted only 3 feet above ground and it worked surpizingly well , considering it's size about 3' in diamiter . If I were in your situation I'd mount it about 1 or 2 feet above the trailer roof. Hope this helps, 73 DAVE KC1DI On Fri, 02 Dec 2005 21:28:26 -0500, wrote: Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/ |
My vertical blew down!!!
I have no trees, streelamps, telephone poles, or anything higher than a
7 foot trailer. That was why I was considering a vertical. For practical purposes anything higher than 40 feet is forbidden and 25 foot is as high as I practically dare do. You could use a mobile antenna on the trailer and have a decent signal. From what I understand, dipoles are not effective below 1/2 wavelength above the dirt, but verticals can work well fairly close to the dirt if they have to. From what I hear inverted vees are slightly better than dipoles but slightly worse than verticals at low altitude. It all depends where you are talking. For NVIS, even a low antenna will do ok. I've run quite a few low dipoles in portable use, and never had any problems. 1/2 wave up? If that were true, my dipoles here at the house would be no good. They are only at 40 ft. Thats barely more than a 1/4 wave up on 40m. 1/8 wave on 80m... I have no trouble at all, and that includes dx. I can work dx on 80m with only 100w no problem. In general, dipoles are better than inv vees at any altitude. At low heights, you have less ground losses, and the antenna is higher above ground in general. But, thats not to say an inv vee won't work ok. It will. A flat dipole is best though, if perfection is desired. Slightly less than low verticals? Who can say. It could be much worse, or much better, depending on the quality of the vertical, the band and path used, etc...In general when camping, I'd rather run a low dipole, than a ground mount vertical with few radials. Any vertical not ground mounted, I consider a ground plane, and it must have resonant radials. Again, it could be better, worse, or about the same... :/ Depends on band, path, etc.. The low dipole would smoke the vertical on NVIS on 40/80, but the vertical might win to long haul dx late at night if it's any good. My wife really doesn't care about money as much as she cares about waste. If I can make my setup working with the stuff I already bought then great... At this point I am considering just throwing in the towel and raising a 20 foot iron pipe to mount a 20 meter inverted vee... sigh. Probably what you should have done in the first place...:/ Would work better than most anything else you will likely try. I would have made my usual fanned paralleled dipoles fed with a single coax if I could squeeze the room, and had a place to tie the ends off. Sounds like you don't really.... 20m is my favorite band, followed by 40 then 30. Why not use the "no radial" verticals? IE: cushcraft R7, and others of it's ilk? Those are good for what you are trying to do... And they will usually work better than a vertical that needs radials, but doesn't have all it needs due to a limited location. Yes, you can use helical radials, radiator, but don't it expect it to be a world beater. A simple dipole would probably eat it for lunch and be cheaper and easier to build. I've used quicky dipoles portable, no higher than my own height, and had no trouble talking. And that was mainly on 75 and 40. One time I did that only running a yeasu ft-7 with 10w output, and had no trouble. That was at Lake Amistad, out in the psuedo desert. Not many trees where we were. I found a tall 6-8 ft stick, and use that to support the dipole. The ends were tied off to low bushes, or whatever.. Even with 10w, I was averaging S9 or so to most people around the state. Not too bad. Would have been 10-20 over 9 with 100w probably. MK |
My vertical blew down!!!
|
My vertical blew down!!!
I actually found what I hope is a solution. The KANGA 33' Telescoping
Fiberglass mast for $99 is guaranteed against breaking or shattering in winds such as I might encounter, free replacement of broken sections if this is so. Weighs only 4 lbs, base is 2 inches. K1CRA, the distributor, suggested that all I needed to do was mount this against my pipe mount with a 2X4 and U-bolts. He also distributes a sealing agent for permanent installations. With this, he said, all I needed to do was run wire up the mast and work against my pipe mount as connected to the overall ground systems. Sometimes it is the obvious which is the hardest to conceive of. I always though high winds and high heights always needed big iron (or copper), but I never thought that something made of an aerospace material would be within my reach... let alone that of a ten foot Pole or a seven foot Texan... I'll let you know how it goes... Thanks, The Eternal Squire |
My vertical blew down!!!
I have no trees, streelamps, telephone poles, or anything higher than a
7 foot trailer. That was why I was considering a vertical. For practical purposes anything higher than 40 feet is forbidden and 25 foot is as high as I practically dare do. ....[snip].... Be patriotic: erect a 33-foot metal-pipe flagpole WITH pulley and rope. Set the bottom of the pole on a strong/thick soda-pop or beer bottle which is restrained to/in the ground somehow (I've buried a concrete block -- with its holes vertical -- until its top is even with the ground surface, put the bottle in one of the holes, and filled the extra space with dirt), mount it firmly to (but insulated from) the top of your trailer, and feed it with coax (connect the coax shield to a ground rod driven through the other hole in the concrete block, the coax center wire to the base of the tower -- I mean flagpole -- and put a 50-100 Kohn resistor across the connection). It'll work quite well by itself on 40 and 15 meters, and if you use an "antenna tuner", you should get acceptable results on 20 and 10 meters (and higher). With an extra inductor at the base, it should give passable results on 80 and maybe even some results on 160. Let your neighbors see you driving in several additional ground rods and laying lots of radials (although I'm usually lazy and just use the wires to the ground rods) "to extend lightning protection". Don't forget to fly a flag occasionally! That's part of the disguise. -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448 NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol) |
My vertical blew down!!!
|
My vertical blew down!!!
Butch Magee wrote: wrote: Hi, It seems that my location boasts 60 to 110 mph winds on a regular basis. I had put up a 1/4 wavelength 20m vertical with 1/8 wavelength radials elevated at 7 feet, with rope guys... and the wind blew it apart like so much tin foil! Does anyone know of a decent commercial design for less than $1000 for a free standing 30 to 40 foot support that can take this darn wind??? Thanks, The Eternal Squire Please tell us where you live to have winds of that magnatude "on a regular basis". I know of a two places like that, not in CONUS of course, the site to the south is inhibited year round by US and Russia, Spain, UK and one or two more that I can't think of right now. Where is your location? " 50 miles west of Gallup, NM." . . New Mexico's answer to Mt. Washington? I Googled him, seems like the biggest wind in his neighborhood is him. KF5DE w3rv |
My vertical blew down!!!
w3rv,
The wind speed I quoted is intermittent, not continuous. I Googled him, seems like the biggest wind in his neighborhood is him. Seems like the biggest bully in the neighborhood is now you. Why don't you put your judgementalism to good use and go beat up on some trolls? The Eternal Squire |
My vertical blew down!!!
|
My vertical blew down!!!
Then you're blind. The difference between a troll and me is that a
troll has harmful intent to seek to divide the group, like Polymath. My intent is simply to ask naive questions that people need to ask but don't because of fear of being punished by people like you. If I'm a troll, then you're an ogre. |
| All times are GMT +1. The time now is 12:58 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com