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Antennas

This page lists a number of resources for the all of us dream, design, and build the last piece of gear that our signals touch, as they race out of the shack.


W2BLC Antenna Links

Our own Gary Skaggs WB5ULK says "I cannot say enough about this website! There are truly DOZENS of build it yourself antenna projects on this site. But for those of you who cannot or do not want to build your own antenna, there is an extensive listing of antenna manufacturers liisted at the bottom of the page. You can also learn a lot more about 'why' an antenna is built that way it is, how much, if any, gain you can expect, and with a little research, you should have a really good antenna to meet your own needs for not a lot of money – if you build it yourself. And I’m a great believer in build-it-yourself-if-you-can antennas!"

http://www.w2blc.net/linkant.htm


Stealth Vertical Antenna

This has to be the original Flagpole Vertical Antenna. This antenna disguises a vertical inside the pole. This is from 1965, and what's old is new again!


Yagi Antenna For Space Reception

Diana Eng has a great article on Make Magazine that talks about building handheld Yagi antennas that can be used to listen, and talk, to the orbiting space satelittes, including the International Space Station. Take a look here, to see how to build your own VHF / UHF antenna setup.


Another $4 Yagi Antenna For Space Reception

Looking for an inexpensive VHF/UHF antenna for space operations, or direction finding? Zed Zed has a great VHF / UHF antenna setup that you can build for cheap.


VHF or UHV - PVC Using 3D Printer

So, you have access to a 3D printer and you're looking for something to build? How about building a VHF or UHF beam with a stick of 1" PVC and a few 3D printed parts. Here on Thingiverse is one that you can build for cheap.


Cheap and simple VHF-/UHF-Yagis

The three previous entries show you four different ways to build a VHF or UHF directional yagi antenna. Once you figure out a construction method, here's a great resource to determine the wire length and spacings of an antenna. DK7ZB has a great VHF / UHF antenna design page on QSL.net that you can use to calcuate the details. It's not very clear, but if you click on the items in the yellow bar at the top of the page, you can select the number of elements and band that you want to build. On these pages you'll see an expected SWR chart, a picture of the assembly, detailed lengths and spacings, and expected gain and pattern charts. Additionally you'll see information on how to stack a pair (or more) of these to increase the gain/pattern effect.


J Antenna Audio Discussion - Denny WA6DKD

Our own Denny WA6DKD is one of our local Antenna Elmers, and he always does a great job on helping us with different antennas. On January 1, 2017, Denny, and DJ walked through the setup of a J Antenna on the 147.06 MHz repeater. This 53 minute discussion walks through design, implementation, theory and construction of one of our favorite antennas.


G7FEK Limited Space Antenna

We have no personal knowledge of this antenna, but it appears to be a great 80/40/30/17/15/12 and maybe 20/10 in only 46' of space. This antenna looks interesting, and we'd love to see it built. If you make this work, let us know at w5nor@w5nor.org.


VHF Tape Measure Yagi

This information is from an ARRL antenna document, which says... The Tape-Measure antenna is a simple, hand-held 2 meter Yagi; that is fun and inexpensive and easily to build. The tape measure antenna is a "home brew" 2 meter antenna made out of PVC pipe and a steel tape measure.

The antenna is useful (especially if you want a portable antenna for back packing etc.) for any radio or satellite use that uses 2 meter frequencies. Here's a great example, thanks to the photography of Michell Carey W5MQC, and the modeling of Victor McDaniel K5VL:

beam connection

These tape measure antennas are similar to the ones shown at local SCARS meetings, and can be built for about $10. Here's a couple links for you to check out:


Bent Dipole Simulations

Let's say you want to put up a dipole antenna, but your property, trees, or other obstructions mean you have to bend the perfect dipole to fit your area. Dick Reid KK4OBI has a great web site that lets you visualize how your antenna will transmit given a ton of variables, like freqency, length, height above ground, and bends in the wires. Here you might get some ideas why your favorite antenna works, and why others don't work so well.


London, Ontario Temporary Car Mount

"I stumbled across the SCARS website and noticed the Bike MS page. I also volunteer for communications with the local MS Bike ride. One thing that caught my attention was the fact that you may need to duct tape onto the vehicles. Our primary support vehicle that we provide communications with are handicap accessible buses. The only area to set a magnetic mount antenna is in the area of the hood as the rest of the body is fiberglass. This provided poor results accessing the repeaters along the route, so a number of London, Ontario hams came up with another idea. This was a collaboration between John Pederson VE3MGR, Mike Watts VE3ACW, Jim Morris VA3AHQ and original testing by Norm Campbell VA3XCN. Norm actually went to the Voyageur bus yard and tested the suction cups on a bus to see if it would work. I thought I would share with you what we have used for the last couple years."

"Components are simple. A 3 suction cup dent puller, a length of 3/4" inch ABS pipe (I used 4 feet), couple worm gear hose clamps, and a ground plane kit for a mobile whip."

suction

"Unfortunately I don’t have a picture with the antenna mounted on the ABS. Since this is used on buses, we mounted the suction cups on a window. This mount works quite well for us. Tested on the side of a Ford Explorer travelling at 70 mph with a Diamond SG-7500NMO mounted on it. Also it supported the weight of a 200 lb man when it was attached to a side window of a bus."

suction

"This may be an option that you could use in the future.

73
John Visser, VA3MSV
London, Ontario"

This is brilliant, just had to use John's words, and we'll be trying some of these next year! Here's some sources of the suction cups... Northern Tool: $10, Walmart Online: $13.50, From China: $28, From China: $38, Harbor Freight: $8, Grainger: $13, Home Depot Online: $20 - Thanks N5HZR


Almost 300 Wire Antennas for Amateur Radio

Iulian Rosu YO3DAC has a great collection of Amateur Radio goodies on his site at QSL.net, but this page gives almost 300 different wire antennas for you to review, covet, and build.


Coming Soon - 20 M PVC Tee Dipole

Our own Ed Hatch AE5DV will be providing details and photographs of his home built PVC Tee 20 M dipole.


Ed's Antennas

eds

This antenna showed up on the SCARS Facebook page from Chuck Crawford and it interested me. Ed's Antennas have exterior vertical antennas for dual VHF/UHF and the 220 ham bands. These antennas are about $30. What's really interesting is that Ed Fong WB6IQN is a university professor, and has sold 16,000 of these antennas over the past 10 years, and the profits go to help his student group. He's even got a +5dB patented gain UHF antenna for $40. All kinds of crazy cable, cable length and connector options. And, you just pay the actual shipping from Santa Monica, CA. Jump on our Facebook Group and ask how it works, there are a couple of these in town!


Using RG-6 for Amateur Radio Feedline

In rebuilding his radio shack, Mark Kleine N5HZR started using quad shield RG-6 coaxial cable for his amateur radio antennas and is reporting very good results.

F to PL259

The pros of using this cable is that it's relatively cheap, (about $.07 per foot), and available everywhere, even at Home Depot. It is also UV resistant, and it's cheap, ($40 for crimper, toner, and connectors), and easy to crimp on F connectors as you need them. There's even F female to PL-259 adapters available for a couple of bucks each to let you connect directly to your radio, or antenna. F female to BNC male adapters are also available if your radio needs those connections. The toolkit is about $33, and you can even directly crimp BNC jacks to the quad shield RG-6.

RG-6 is used with frequencies up to 3 GHz, and the cable has great loss number in the ham bands. For example, this chart shows that at 10 MHz, RG-6 loss is .6 db / 100, RG-58 is 1.4 db / 100, and RG-8X loss is 1.0 db / 100. We recently used a 250 foot segment of RG-6 at Field Day, and the system performed without any issues. Loss figures at 10 MHz would be 1.5 db, slightly lower than the 2.5 db of RG-8X, or 4.5 db of RG-58.

The cons of using RG-6 is that the characteristic impedance of this cable is 75 Ohms, and hams are used to cable that has a characteristic impedance of 50 Ohms. Most radio gear transmitter ports typically state that they have a 50 Ohm output. Since all of antenna work is a compromise, this difference may be more academic than problematic. For example, a 1/2 wave dipole, that is mounted 1/2 wave above ground presents a 72 Ohm load. So, even using 50 Ohm cable presents issues with impedance. Belden, a major cable manufacturer has a page that talks of why 50 Ohm cable was selected.

So, like everything else with amateur radio, it matters less what you use, it matters more that you DO something.


Horizontal Loop Antenna Construction

Horizontal loop antennas are a great way to start building your wire antenna farm. The idea of these antennas is that you build a wire loop that connects your coas tip, with the coas shield, and hang that wire in the air. This works best when you capture the largest area inside the loop. By the math, this means a circle, but those get hard to hang. Typically you'll find square and triangular (delta) loop antennnas are the easiest to hang. Other irregular forms are very acceptable. Randy Davis K5RCD, from the San Antonio, TX area has a great web page that explains how to design, build, and operate this type of antenna.


Skywire Loop Antenna

Some call it a Skywire Loop Antenna, some call it a W0MHS Loop Skywire Antenna, nowadays it's called a Full Wave Loop Antenna but it still is a force to be reckoned with. 574' of wire for a 160 M full wave antenna that tunes 160 M through 10 M. With a remote tuner attached at the feed point, this antenna tunes it all. Jason Buchanan has a great page that explains his efforts in building one of these antennas.


Resonant Wire Antenna Efficiency

Our own Kenn Goodson KA5KXW found a white paper by David J. Jeffries that was published in the antenneX journal in Issue No. 119 – March 2007. This PDF version of the paper talks about the different materials that can be used to build amatuer radio antennas. Here he compares these different materials: silver, copper, steel, gold, aluminum, brass, tin, lead, stainless steel, tin-lead solder, and zinc. This is a great study that ends up showing the power loss per 100 watts in each of the different materials. The results are fairly obvious, BUT what you'll find is that there's only a couple watts, per 100, difference between the best copper, and the steel/aluminum wire that you may be tempted to use. So, like the rest of amateur radio, use what you've got.


PVC/Copper Pipe 2 M Vertical Dipole

Jim Feldman W6JMF builds an odd 2 meter vertical dipole, that can be portable, or mount on a vertical surface. Everything you need to build this antenna can be found on this page.