I’ve been working on another temporary antenna for use in my city lot during contests. You’ll recall my Moxon Beam for 15 meters that’s done such a great job on that band. I’ve been looking for something that would work on 20 and 10 meters as well, and maybe 40 meters. I came across a great write-up by Sam Moore, NX5Z, in the March 2011 QST, titled “A Four Wire Steerable V Beam for 10 through 40 meters”. That antenna requires a great deal more real estate than I have available, but I figured if I could get something pointed to Europe, I’d be doing just fine. I found a 35 foot push up steel mast on ebay and picked it up. I added a 4:1 balun from Design Baluns and the spool of 14 guage stranded wire I already had for the legs. Then I looked at how best to get the mast vertical in the most advantageous part of the yard. On Memorial Day, I found the free time to try it all out. You can see some photos nearby. After it was all up I conducted some measurements. I found that from 10 meters through 30 meters, I had a VSWR of roughly 2.5. Not the best but a level that would allow me to run coax from the 4:1 balun to my K3’s internal antenna tuner without too much loss. That saved me from running twin lead to a nearby remote antenna tuner. I also note that 40/80/160 have VSWR around 4. This means I should give some consideration to putting in place a 1:1 balun for using the antenna for the low bands, where it no doubt acts more like a low hanging dipole. That could perhaps work well for NAQP and Sweepstakes. Something to consider.
Unfortunately, once everything was in the air, I was first only able to get 65 feet of wire into play for each leg of the antenna. Then the angles of the wires came out to 60 degrees and 100 degrees. This would put center aim at roughly 80 degrees, way off the mark for Europe. If I moved the mast closer to the backyard fence, it looks like the north leg’s angle would improve to 50 degrees, which might bring Southern Europe and Northern Africa into play. On air testing revealed the directivity that I was seeking, but not sure I’m going to be happy with the aim. My thought right now is to put the Moxon on top of the push up mast, which would be a big improvement over the painter pole I’m using now. Now I need to spend some time thinking about how to get the Moxon mounted and up into the air. Stand by for more ham radio adventures!
Hello Jim, I too read NX5Z’s article in QST. Since I had every thing I needed & a yard surrounded with 50 ft. plus red pine trees I thought I’d give the V beam a shot. With compass in hand & a reel up tape I plotted out a beam aimed at my weak spot; Asia. One leg is perfectly N & S 360 deg.. The other is exactly 312 deg. N NW. That config. gives me a heading of 336deg. from my QTH in N Mich. I was able to use 106ft. legs. My feed point is at 50ft. up & the legs are 15ft. above ground. I had a 9 to one balun on the shelf & some JSC 3500 left over from another project, so; that is what I used. WOW ; my expectations are being exceded. In the last few weeks I have added China, Taiwan,Mongolia, Vietnam,Micronesia, Indonesia, Pa Pua New Guinea etc.., & I get great sig reports from Japan,New Zealand etc..etc.. Wish I had a way to model this ant. I will add other legs when I can find suitable relays. The back side perks well too for South America & I just QSO’d the S Shetland Isl.; Anartica. This project has proven to be well worth the effort. Great hobby; Great fun. 73, Rich K8TAO 16 Dec 2012
Rich,
Great news on the effectiveness of your vee-beam. It sounds like you’ve got just the right length and angle to the desired locations. I’d like to hit those locations myself! I will certainly keep this option in mind if I ever get onto a larger property. Thanks for sharing your results.
73, Jim, K5ND
ZS1RJQ forgot to mention long path to USA from Cape Town was on 40 meters.
You can add drop legs to the end of the antenna, furthest ends from feed. This will give you an even lower angle take off. Its works for me, California long path from Cape Town on 100w. Now thats over the Indian ocean and Pacific, 15000Km not bad me thinks. ZS1RJQ Michael.
can you tell us more about ‘drop legs’?
iv been modeling in 4nec and find my 65ft tower is not much help for 20-10 meters
but helps some on 30 and 40m v beam…. what really showed was the neeed to have the far end supports up 1/2 wave from the ground… working on that now.
i have some photo to share.
brad
ko6kL
Hi folks I have been trying the 106 ft V-beam also.
I was looking for more signal heading East from my home here in California.
The V is feed with 450ohm ladder line and is hung about 2 ft off my rohn-25 tower at about 65ft high , the far ends are supported by 20ft fiberglass poles used for knocking almonds ( Hardware store $40 )
i think the math works out to 40ft spacing between the pole legs at the far end for that 45 deg. setup from QST , ( my spacing was less )
the MUF has been low and my free time during the day has limited my play time with this new antenna but it’s working much better then the R7 vert. on 15m and most of the time on 20m , I can hear station better on it most of the time and got about a 2 S-unit kick on most of the signal reports so far on 15m
have not had much 10m reports … 12m was very good.
hoping to scope out the yard again this weekend and see if i can find room for more legs and start on that relay box , i think the 450ohm feed really helps cut down on the multi-band loss , i ran the line to a mfj tuner on my ham desk… and also want to get a better balun , the 4-1 current was recommend.
catch you on the bands
brad
ko6kL
webpages.charter.net/partytown/sstvcam.htm
im still working on this 4 wire v beam , the relay box is ready , is there a 4nec2 file for the antenna ??
I’m not sure where you’d find the NEC file. Perhaps the original QST article would be a good starting point. That and a Google search.
Good luck with your antenna. 73, Jim, K5ND
the 40m v beam nec file wont run more then 1 time for me , just wondering it apex at 60ft and end supports at 30 ft will be ok or better then say 30ft for everything….
Sorry that I don’t have any information on the nec file. I’ve never worked with this before. Perhaps the original author of the QST article can offer insight.
73, Jim, K5ND
I put up my 30 foot high flat top Vee Beam with a 40 degree aperture. Hand wound 4:1 voltage balum. 2-3 SWR from 160m to 6m with a 1:1 SWR dip at 59Mhz & 22 Mhz. Offset fed, one leg is 106′ the other is 112′ . 50′ 213 coax to tuner, so perfect on any frequency. World wide contacts with 100 watts. Especially on 10 & 12m. Still in the experimenting stages, next more balum, maybe current 4:1?? Perhaps some open feeder. Not terminated, does have a couple of radials going out the rear for 50′. Ground rod connected from the tuner. On my HOA lot I have 3 trees. One in each of the back yard corner & one dead center in the front, so a Vee Beam was a given from the start! Thanks for this page & 73’s. KG5KSG
Sounds like a great set up, particularly in an HOA. 73, Jim, K5ND
Doug the modeling I did with off center feed vbeams didnt look very good the pattern got all side ways , also I think it would work better with 450 ohm line , i have a small v with coax and it is very much dead compared to the 450ohm fead one , lots of loss , to much for off frequency use…
I have some radation patterns on my profile on qrz.com
brad
ko6kL
Hello Brad,
After going back with 12AWG solid wire, I placed 10 turns on the Balum & saw 1:1 on 3750mhz! And now it will operate on 160m through my tuner. It goes over my foor from the center of the lot to each rear corner, thanks to some 30″ tall “post oak” trees, with each 30″ tall 1 1/4″ conduit mast bolted to the tree trunk. I can hoist at any of the 3 masts. The ham universe link on your QRZ page. And yes, 20m is not an option with my Clipperton L at this point, out of the rig w/ tuner it operates perfect on all bands at 1:1. The HOA deal w/ the Vee Beam, it’s a 30′ flat top & not readily an eye sore, so far not an issue with the masts painted black.
I will try the twin lead next perhaps, maybe purchase a bag of the 12awg THHN black plastic clips at the Belton Hamfest coming up this fall. This antenna really shines above 20m where it has the gain of over the 3/2 mark. Best contact was S. Africa on 100 watts. 18m, 12m, & 10m especially pointing NW & SE with a 40 degree aperture.
73’s
Doug
KG5KSG
[…] Vee Beam […]
MARVIN W WHEELER kg7v Ideal to put up Vee Beam wire antenna.
He,s antenna expert when he came over to my house.
Jeff KB7QAG General