Survivalism & Self Sufficiency Topics > Amateur Radio How-To's

All Band Single Wire Antenna,The Zeppelin

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Carl:

--- Quote from: Smurf Hunter on February 10, 2015, 05:06:37 PM ---Regarding "ladder line", is there a common name that non-hams use?  When I call local shops asking, they claim they've never heard of it.

There are several 450ohm ladder line based antennas I want to try out, so I figure buying a good length of it would be worth my time and education.

--- End quote ---

Ladder Line is what it is: 300 or 450 Ohm...no resistance involved...either size works. TV TWIN LEAD also works ,but just the kind with two conductors and not the shielded type...but TV antennas and twin lead are pretty much relics now.   

Some shops may call it "Window Line" but it's been years since I heard it called that.

http://www.randl.com/shop/catalog/index.php?cPath=11080

Canadian Prepper:

--- Quote from: Carl on February 07, 2015, 01:23:30 PM ---This is a very different antenna by todays standards but it is easy and effective and works well
on 10 through 80 meters with use of a tuner . It is easy to describe and build.

It is a COAX FED 4 to 1 balun attached to a 17 foot long piece of 450 ohm ladder line
and a 67 foot long piece of wire attached to one side of the ladder line. This antenna will work
with gain and does well horizontal at 10 feet above earth as an NVIS antenna .

If 92 feet of wire is used instead of 67 ,it can even cover 160 meters and all bands to 10 meters.



I use a version of this and often call it my End Fed Half wave...67 feet of wire and a 17 foot 6 inch wire attached to a 4 to one balun for 6 through 80 meters, or 35 and 17'6" for 6 through 40 meters...it is easy and effective and you can carry it in a pocket.

--- End quote ---

Hi again Carl, and I hope you don't mind my asking a flood of questions to make sure that I get things right....

So if I understand correctly, we're talking about two slightly different antennas (not counting the different lengths for 40, 18 and 160m.

The first is essentially an end fed zep with 67ft of wire attached by 17ft of 450ohm ladder line to a 4:1 balun, plus coax to the shack, and by lengthening it to 92ft can make it suitable for 160m and probably tune better on 80m than the 67 foot version.

You then speak of a more portable antenna, which consists of a balun, wire, plus 17.5 ft of wire attached to the balun, I presume to act as counterpoise? If I were to first try this latter design (I could pick the required parts up tomorrow, but actually have to order the ladder line around here as my local ham outlet only has 300ohm line at $60 for 100 feet!), would I need another length for the counterpoise if I'm matching it to 92 feet of wire for 160/80m? And since I have both an LDG auto-tuner for my 987D, but also an MFJ 949E manual tuner available, might the latter be more suitable for tuning an end fed wire?

And aside from the parts listed above, I presume that I'd need to solder the wire to the balun (elementary question I know, but it sounds like it's about time I get a solder gun). If I get the ladder line later, I'd then just solder the end of the 92ft length of wire to one wire from the ladder line. For baluns, I noticed that my local store has the following in stock: http://radioworld.ca/rba-41-p-5743.html  http://radioworld.ca/w2au-p-3229.html and http://radioworld.ca/mfj-913-p-6591.html 

Any recommendations for which balun to use? The first is primarily meant for twin lead, but would I be able to use if for the simpler two wire design, at least until I get some twin lead? The second balun looks appealing since it's rated to 1000w, which might make it useful if I eventually get a 500w amplifier down the road, while the third, an MFJ product indicates that it's a current balun, which I noticed from the other links that you've posted might be significant.

If I just add a few plastic or ceramic insulators and zig-zag the antenna across the yard, probably a bit under 10ft to start, I could set up and take it down without waiting for access to the upstairs balcony/roof, etc. and do NVIS right away. I'd basically try to keep the wire/balun at least three feet away from any metal, and make sure that none of my bends are at less than 90% to ensure that the wire does not interfere with itself.

Later, if I add the ladder line and try to get the antenna higher, would it make a big difference if different sections have to be at different heights? I'd currently have it at about 17ft high from the ladder line end and could string about 50ft of the wire across to a tree at about 20 plus to maybe 30 feet, but it will need to be supported at a lower height for some distance after that and at the final endpoint, probably back to 17 feet.

All of the other antenna options that I've discussed on other threads remain dependent upon factors that might take months to work out, so I'm really interested in figuring out if this might offer the fastest solution to my 80m woes. If I have to settle for NVIS for now and can later get the wire high enough for longer distance comms if circumstances warrant, this would fill the biggest gap in my ham capabilities up to the present time. Even if I end up eventually putting a full length or shortened 80m and up dipole on our roof, I can see this remaining useful both at home (where I'd still like the option of operating NVIS) and as a portable device.

Carl:

--- Quote from: Canadian Prepper on February 11, 2015, 03:40:31 PM ---Hi again Carl, and I hope you don't mind my asking a flood of questions to make sure that I get things right....

So if I understand correctly, we're talking about two slightly different antennas (not counting the different lengths for 40, 18 and 160m.

The first is essentially an end fed zep with 67ft of wire attached by 17ft of 450ohm ladder line to a 4:1 balun, plus coax to the shack, and by lengthening it to 92ft can make it suitable for 160m and probably tune better on 80m than the 67 foot version.

You then speak of a more portable antenna, which consists of a balun, wire, plus 17.5 ft of wire attached to the balun, I presume to act as counterpoise? If I were to first try this latter design (I could pick the required parts up tomorrow, but actually have to order the ladder line around here as my local ham outlet only has 300ohm line at $60 for 100 feet!), would I need another length for the counterpoise if I'm matching it to 92 feet of wire for 160/80m? And since I have both an LDG auto-tuner for my 987D, but also an MFJ 949E manual tuner available, might the latter be more suitable for tuning an end fed wire?

*** The two antennas are very similar and act and tune much the same. The 17 or 17 1/2 foot counterpoise on either must be kept above ground (a few inches or feet) and is more contained as ladder line. The version with 'regular wire only' was first done on a wooden fence in an antenna restricted area with the 17 1/2 foot section along about a foot off the ground and the longer wire at the 5 foot level along the top of the wood fence. I used the wire only version along side a wire and ladder line version with no difference in signal TX or RX BUT the ladder line version works a bit more stable and looked more like an antenna for my shack. The constant position of the ladder line seems a bit more stable with variance of ground (wet/dry soil) but that may be just my soil.****



And aside from the parts listed above, I presume that I'd need to solder the wire to the balun (elementary question I know, but it sounds like it's about time I get a solder gun). If I get the ladder line later, I'd then just solder the end of the 92ft length of wire to one wire from the ladder line.

******Until you decide on a build ,I would use wire nuts or other temporary connect at the balun to save wear and tear BUT solder the final product to prevent oxidation from doing crazy things with your connections. ********


For baluns, I noticed that my local store has the following in stock: http://radioworld.ca/rba-41-p-5743.html  http://radioworld.ca/w2au-p-3229.html and http://radioworld.ca/mfj-913-p-6591.html 

**** Looks like one of the ones I use...Tie wire to the EYE HOOKS for strength and then connect the copper wire from internals of balun to you wire so that you avoid stress on the balun internal works****

Any recommendations for which balun to use? The first is primarily meant for twin lead, but would I be able to use if for the simpler two wire design, at least until I get some twin lead? The second balun looks appealing since it's rated to 1000w, which might make it useful if I eventually get a 500w amplifier down the road, while the third, an MFJ product indicates that it's a current balun, which I noticed from the other links that you've posted might be significant.


****The MFJ 1000 watt will work better for either form as the LDG is more a temporary balun as the 5 way binding posts are not the best for permanent installs , I use both types and would only use the LDG if the wire and balun were held stable from wind motion.****

If I just add a few plastic or ceramic insulators and zig-zag the antenna across the yard, probably a bit under 10ft to start, I could set up and take it down without waiting for access to the upstairs balcony/roof, etc. and do NVIS right away. I'd basically try to keep the wire/balun at least three feet away from any metal, and make sure that none of my bends are at less than 90% to ensure that the wire does not interfere with itself.


***** 90 degrees is not set in stone ,it just insures minimum interaction and maintains predictable SWR , I have folded the wire within 20 degrees of itself (3 feet separation in 15 feet) but it caused a need for about 5% more wire length. When you move above the low 10 foot level,TUNE will change...but the tuner and balun allow a lot of room for this.*****

Later, if I add the ladder line and try to get the antenna higher, would it make a big difference if different sections have to be at different heights? I'd currently have it at about 17ft high from the ladder line end and could string about 50ft of the wire across to a tree at about 20 plus to maybe 30 feet, but it will need to be supported at a lower height for some distance after that and at the final endpoint, probably back to 17 feet.

****Don't worry about different height or direction of your wire,it does effect radiation pattern,but you probably won't worry how it maps out when you find how it works for you over your soil and near whatever conductors that effect it,each antenna is different.*******

All of the other antenna options that I've discussed on other threads remain dependent upon factors that might take months to work out, so I'm really interested in figuring out if this might offer the fastest solution to my 80m woes. If I have to settle for NVIS for now and can later get the wire high enough for longer distance comms if circumstances warrant, this would fill the biggest gap in my ham capabilities up to the present time. Even if I end up eventually putting a full length or shortened 80m and up dipole on our roof, I can see this remaining useful both at home (where I'd still like the option of operating NVIS) and as a portable device.

--- End quote ---

Every part of this antenna can be used in many different forms,like legos, there is no end to what can be done .Here is some reading about SWR and antennas that answers many questions .Just read each page and link to the next as antennas and SWR become much less a mystery.


OH just in case ...BUILD the wire only version and get it on the air. We might make some changes later if you have band tuning issues..The manual tune may have a bit more range than the auto tuner but I think the LDG will do well for you as it does for me. Plus...if tuning or stability is  noticed ,a second 17 foot or so counterpoise or maybe an earth ground may be the fix. I had a bit of RF in my shack until I used an earth ground.

http://www.qsl.net/arrlsb/Digest/Pages/Antennas/antennas03.html

Canadian Prepper:
Thanks Carl!

So I'll plan on picking up 125ft of stranded copper wire ($30 Cdn) and a W4:1 balun ($35) and perhaps another two or three ceramic insulators (I've got at least two here at home). The precise height and pattern will invariably be a trial and error process, and will probably be adjusted whenever I might get the ladder line. I'll may start very low but might go higher it it's easier to keep clear of any metal objects or branches that way.


I noticed in the notes above that you speak of a 92foot wire for 160/8m and higher frequencies at one point, but then speak of 85ft and the 17ft counterpoise elsewhere for 80m use (which interestingly enough totals the overall length of a G5RV). Since it's easier to start long and trim back, perhaps I'll try to cut 17.5 feet for the counterpoise and start with the 117-118feet that would be remaining, unless you'd think that it might be better to cut it closer to 92 feet (plus 1-2 feet for fudge factor) right from the start.

I realize that the articles that you link to suggest that I not fret too much about getting close to half wavelength on my preferred band, but if I'm focusing on 80m, would there be any cons to going all out and laying a 133 ft. wire plus 17 ft counterpoise (from a 150ft roll) if it can be fit into my space? If I later decide to shorten the long wire to 92 or 85 feet I could always use the extra wire to make a second 17ft counterpoise.

Though I'll probably experiment with it both ways, should I expect that having another dipole cross the yard at a slightly higher height to interfere with the long wire? Since the main point of this experiment is to get on 80m, I'd happily rely upon the dipole for higher bands and switch to the wire for when I want to work 80m and NVIS.

Another quick point: since the ONTARS 80m nets operate almost every hour daily from 7am to 5pm, that would offer lots of opportunity to check the antenna's TX and RX, as well as the effect of various adjustments to length, operating height, etc. I could easily do that in between other activities around the QTH and wouldn't be adverse to trying it on some local 40m nets or even ongoing 20m continental nets like those found at 14.300Mhz. And I'll naturally test it across all of the available bands from 160-10m to see which bands the tuner can handle. Perhaps I'll even take down the dipole for a week or so to play around with this setup at various times and frequencies.

I'm getting stoked at the idea of being able to play around with this until the opportunity arrives to install something on the roof!

Canadian Prepper:
Quick addendum: I see now why 84-85 feet and 17 foot counterpoise was chosen, as well as the longer lengths that help versus which ones to avoid: http://udel.edu/~mm/ham/randomWire/. It's a case of trying to avoid multiples of half wavelengths which are harder for the tuner to match. There's lots of articles about the length combination above from 1936 to present, and a chart at the link above indicating which other lengths might work best for particular bands.





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