Posted: 1/30/2010 10:28:22 AM EDT
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One of our young ARFCOM new hams is in college and needs something he can set up, take down quickly. And will cover as many HF bands as possible with the least stuff... KISS.
This is what I came up with. It is a Carolina Windom. 4:1 Balun. But with a twist. One side is 41'. I have two pieces that can be interchanged for the other side. A 25' piece, along with the 41' piece makes a Windom with 40 meters the lowest band. It is 66' overall length. 
The 25' piece can be replaced with an 89' piece, making a Windom with 80 meters as the lowest band, overall length 41' + 89' = 130' total. 
Anderson PowerPoles for electrical connection. Some clips from the hardware store to connect the wire legs to the eyebolts on the balun. Ceramic dogbone insulators on the ends. I'll also be sending him a hank of 550 Parachute Cord and some LMR-200 coax (same size as RG-58, but lower loss and much higher power rating) with 10 Palomar Engineers snap on ferrite beads as a choke balun. This will be something he can put up, take down in a few minutes, bring home, whatever. That is all. Carry on. |
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Quoted:
Very nice... extremely nice. Say, would it be possible to get a close up on the center with the connectors? I just want to see how you did it. Thanks. Of course! The wire passes through the loop on the hook, is twisted around itself, and has heat shrink tubing to keep it from unwrapping. Now here's an important "trick" in doing this... make sure you slip the heat shrink over the wire BEFORE you twist the wire onto itself. 
And these are Ferrite Snap On Beads (p/n FSB-1/4) from Palomar Engineers. Their purpose is to stop RF from running down the shield of the coax and getting back in the shack. Many 1:1 "Choke baluns" are actually just a bunch of ferrite beads. The same ferrite beads can also be bought from Ham City listed as p/n RCT-2 under Chokes on the left side of the page. 10 beads are needed for lowest band 80 meters. 5 beads are needed if the lowest band used is 40 meters, but having all 10 beads on there does not hurt the higher bands. Note there is a small blue ty-wrap around the coax to hold the beads up in place. While these beads snap on tightly on LMR-240 or RG-8X, they slide up and down on the smaller LMR-200 or RG-58. This Coax is LMR-200, and is good up to 1000 watts. For low power (under 300 watts) use RG-58 or RG-8X could have also been used, but I had just removed this perfectly good coax from my antenna and replaced it with LMR-240 (rated 1300 watts) for a little more safety margin with my 800 watt amp in my station. This LMR-200 seemed to be just the thing to hang out of a dormitory room window. 
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Of course, if this were to be a permanent antenna for myself, I would not have used the clips. I would have just tied off the wires to the eyehooks on the balun. I would not have used the Anderson PowerPole connectors, but rather just twisted the wire connections together and soldered.
And after screwing the coax to the 4:1 balun, I'd wrap the connector and socket with electrical tape and coax seal. Helpful hint... First spray the plug and socket with Corrosion Guard or Corrosion-X. Screw them together and wipe off the excess spray. Next, wrap the connection with 3M electrical tape (3M because the adhesive does not turn gummy with time like the cheap stuff), but wrap it adhesive side out. Why? So the stuff we use in the following step does not stick to the plug. Begin all wrapping at the bottom and make overlapping turns going up. Now, wrap the connection with Coax Seal or Scotch 130C butyl rubber tape. This stuff is black tape that looks like electrical tape, but is very thick and soft rubber. In the heat of the sun it soon adheres to itself forming one big rubbery mass. Finally, wrap the connection a final time with electrical tape, pulling and stretching it as you go, from the bottom up in overlapping turns. When you get to the top, for your last wrap relax the pull, cut the tape and press it in place. By relaxing the pull on the tape it won't pull loose and start unraveling. Note also that on this brand of balun, the Unadilla 4:1 balun, http://www.universal-radio.com/catalog/antsup/1888.html that there are two "weep holes" on the bottom of the balun so that it needs to be turned down to keep water out. Also, when you wrap it, be careful to not block the weepholes. But for our young Arfcom ham, setting this antenna up temporarily, just wrapping it with electrical tape only will have to do. |
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I've used this tape for sealing co-ax connections and been 110% pleased. Much much easier to work with than butyl rubber and electical tape.
cell-tape |
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Quoted:
I've used this tape for sealing co-ax connections and been 110% pleased. Much much easier to work with than butyl rubber and electical tape. cell-tape Thanks for the tip! |
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I was asked to post a bill of materials:
4:1 Balun http://www.universal-radio.com/catalog/antsup/1888.html End Insulators http://www.universal-radio.com/catalog/antsup/3250.html but other end insulators would work, such as http://www.universal-radio.com/catalog/antsup/4818.html Wire 14 ga insulated stranded copper, from a 500' roll available at Home Depot. A LOT of antennas can be made from one roll, just $25.00 USD. Heat shrink tubing to secure the ends, 1/2" Anderson PowerPoles, 30 amp size. Crimped AND soldered. Item #2228 on this page. http://www.universal-radio.com/catalog/hamps/2231.html The snap hooks, from the hardware store. Not marked as to manufacturer. They had various sizes, and I got the smallest size, which fit in the balun's eye hooks. Larger snap hooks did not. Ferrite beads, 10 required: Palomar Engineers, FSB-1/4 http://www.palomar-engineers.com/Ferrite_Beads/ferrite_beads.html or same item Ham City, RCT-2 https://www.hamcity.com/store/pc/viewPrd.asp?idcategory=655&idproduct=1830 Also available, RCT-2 from www.radiodan.com |
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I don't know how I missed this one. Radio Works uses a 30-35 foot length of coax between the balun and the as they call it a line isolator. Are the beads doing the same thing as the isolator? Also you did not mention does the beaded end go on the balun or the radio. Wondering if maybe I took a ~35 foot length of coax from the balun then added the beads if I would not end up with same thing as Radio works. I like your idea and may use it to replace my broken windom. I hear bad things lately about Radio Works line isolator weeping water in around the SO239 connector and I don't want to chance it with a replacement. |
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Quoted:
I don't know how I missed this one. Radio Works uses a 30-35 foot length of coax between the balun and the as they call it a line isolator. Are the beads doing the same thing as the isolator? Yes. Also you did not mention does the beaded end go on the balun or the radio.
Up by the balun. Some OCF dipoles have the choke (or line isolator) right up by the balun, and some have it down 10' for 40 meters, or down 20' for 80 meters. Wondering if maybe I took a ~35 foot length of coax from the balun then added the beads if I would not end up with same thing as Radio works.
As per previous reply. |
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Quoted: Thanks just waiting for warmer weather.Quoted: I don't know how I missed this one. Radio Works uses a 30-35 foot length of coax between the balun and the as they call it a line isolator. Are the beads doing the same thing as the isolator? Yes. Also you did not mention does the beaded end go on the balun or the radio. Up by the balun. Some OCF dipoles have the choke (or line isolator) right up by the balun, and some have it down 10' for 40 meters, or down 20' for 80 meters. Wondering if maybe I took a ~35 foot length of coax from the balun then added the beads if I would not end up with same thing as Radio works. As per previous reply. |
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You know, Big Daddy... something like that would roll up and fit in a Pelican 1550 that I am currently bolting a radio into.
It will contain an Icom 718, Samlex SEC-1223 power supply, LDG IT-100 tuner, with room left over. This, 50'-100' of RG-8X and some parachute cord... I think it will all fit. 
Yeah, I have all the parts to build another, too. |
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Quoted:
I've used this tape for sealing co-ax connections and been 110% pleased. Much much easier to work with than butyl rubber and electical tape. cell-tape I got this advice from a long time commercial radio tech and ham years ago, and it has proven very true. The best stuff for sealing coax is the cheap, low quality electrical tape you can buy at truck stops and the dollar store. Exposed to the elements in pretty short order it congeals into a sticky mess that makes a great seal. Good quality tape keeps its form and eventually breaks down and will start to unravel, but the cheap stuff just becomes a gooey, watertight mess that you have to cut off. I took an old quarter wave ground plane I had made when I first became a ham off my store roof not long ago, it had been up at least 11 years. The coax was cracking, the coat hanger elements were rusted, the PVC supporting it had cracked, but that crappy 99 cent electrical tape was still a gooey mess that was still sealing it. |
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Quoted:
The best stuff for sealing coax is the cheap, low quality electrical tape you can buy at truck stops and the dollar store. Exposed to the elements in pretty short order it congeals into a sticky mess that makes a great seal. Good quality tape keeps its form and eventually breaks down and will start to unravel, but the cheap stuff just becomes a gooey, watertight mess that you have to cut off. That's a great bit of advice, Garand_Shooter. Thanks! 
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Quoted:
Quoted:
It will contain an Icom 718 I was wondering what you did with the IC-718 you replaced with the Ten-Tec Jupiter.....it's all coming together now. No, actually I have TWO IC-718's... one was my main rig (until the Jupiter arrived) and the other was my spare / field day / emergency / backup / etc rig. I originally had a FT-897 which the menu system just whipped me. I had bought a 718 as a backup rig. I liked the 718 so much it became my main rig, and I sold the 897. I then was short a backup, standby, spare, etc, radio... so I bought another one... the one that is now going into the Pelican case. A nice deal on it... bought it from a ham about 50 miles away who had won it at the big area hamfest the year before. He had only used it about 30 minutes just to see if it worked. It looked new. The other 718, the one that was my main rig is now sitting over on the side, looking dejected, the Jupiter having taken its place. I don't know what I will do with that one. |
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Quoted:
Wire 14 ga insulated stranded copper, from a 500' roll available at Home Depot. A LOT of antennas can be made from one roll, just $25.00 USD. AFM, is this the same type of wire you used? I got this today at Home Depot, but it cost me $36.50. You get a Senior Citizen's discount? 
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That's the stuff. No, I just paid $25.00. But that was a year ago. Copper has been going up.
Same wire, I just bought another roll at Home Depot. It is by Southwire, but is similarly packaged. I had to pay $39 (that includes sales tax). Ouch! But I DID buy it for $25 about a year ago. |
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That's the stuff. No, I just paid $25.00. But that was a year ago. Copper has been going up. Thanks. The rest of the stuff to make one of these antennas is en route. I've been checking out some of the large trees in the woods behind our house for their "support". Have you heard of anyone using one in their attic? I think our house is only about 45' wide, though. Quoted:
If you have any non ferrous recyclers around you, go and ask them if they have any spools of that wire they want to get rid of. I get those rolls of wire for scrap prices. I'll have to check out that idea, but I think 500' of wire will probably keep me busy for a little while.
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Attic is not big enough for this Windom.
For attic, try this: 
Make the ends 1' longer than shown and fold back on itself. I use tie wraps to keep the ends doubled back. Then let out a little or take in a little as needed. Adjust the ends of the red/blue segments for the 75 meter band. Adjust the ends of the brown/green segments for the 40 meter band. Keep the ends away from anything but air. High voltage is present on the end of any antenna. Do not staple to rafters. Use standoffs. This won't work with a metal roof, of course. |
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Quoted:
I've used this tape for sealing co-ax connections and been 110% pleased. Much much easier to work with than butyl rubber and electical tape. cell-tape I just got some in from N9TAX, the guy that makes the great roll up ladder line Slim Jim antennas for 2m/70cm, on his site sold under the "Rescue Tape" label. http://www.2wayelectronix.com/6-Rescue-Tape-12-Roll-Restape.htm Thanks for the tip! |
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