SOTABEAMS Linked Dipole

This is an in-depth look at a 20m/40m SOTABEAMS linked dipole. I try to point out every interesting facet of this cleverly engineered dipole system.
I use this antenna frequently to work portable QRP. It's a pleasure to use and it works great.
Very highly recommended!

[@richardnday]

After watching this video a month ago, I bought this antenna. It is fantastic. I have used it once with my FT-817 and made several contacts. Yes, I could have built one of these antennas, but why bother. Nothing I could make would be quite a slick as this one. I really enjoy your videos and I have learned a great deal from your very structured, easy to understand productions. They are flawless. Keep up the good work.

[@allenbraydon7032]

I guess Im asking the wrong place but does someone know a method to log back into an instagram account? I somehow forgot the account password. I love any tricks you can offer me!

[@angelian6260]

@Allen Braydon instablaster =)

[@theoldhobbit3640]

Great video, thank you. As a UK operator (M6KVK) Sotabeam has supplied quite a bit of my QRP kit, including the antenna wire from which I make my own antennas. They are a great little company and I have nothing but good things to say about them. I too have a selection of linked dipoles and spare winders and my next purchase will be their mountain top tuner. Thanks again for the video.

[@AmateurRadio-2PW]

These videos are fantastic. I am new to HAM and the way you explain things is "Teacher Perfect", I have figured out more things from you in 2 hours than I have in 3 days of internet research and I am talking about picking up on little things you probably think are of little importance but to me they are key factors in honing the art. Thank you a bunch for your efforts 73s...Adam, Sydney Australia

[@QRPSchool]

This is very kind of you, Adam. Thank you for your encouragement. - Cliff

[@kelpfl]

I am a newly licensed Tech (KC3ITL) with no Elmer so I rely heavily on the internet to understand everything that is not (and even is) on the exam. Your videos have been beyond valuable to me as I slam my head into issue after issue. Your golf ball solution to raise a dipole was brilliant and my 10 meter wire is attached to 60 lb test to be raised up approx 35 feet whenever I want to use it. Too many other helpful tips to mention, but you have a loyal follower.

[@QRPSchool]

Hey, Andy! Congrats on getting that Technician's license and for caring about HF radio. (A lot of Techs stop at VHF/UHF) I'm happy that you find my videos helpful. It means a lot to me. -Cliff

[@kelpfl]

Thanks Cliff. Is there any chance I could send you images of the station I built? I would appreciate your suggestions. Having built everything without external input, and I am confident that I made mistakes. Thanks again. Andy

[@QRPSchool]

I'm not sure how I could help but I'm happy to try. - Cliff

[@bluesaloon22]

I have been using a linked dipole as my home station antenna for a couple of years. It covers 10/12/15/17/20m and is made from NATO D10 field telephone wire. I've had stations tell me I should just buy a tuner, but I only need to drop the fishing pole centre by 1 section to access the links. Not a huge hassle. Very quick and I need to walk past the kettle on the way, resulting in a fresh band and a fresh cup of tea. I always compare a linked dipole to "Russian Dolls" when explaining the concept. So simple it's genius! 73, de mm6wer.

[@QRPSchool]

Agreed, James! I like resonant antennas for QRP. When every watt counts, it's best to use an efficient antenna. As others have said, "It's not hard to make a dipole but it's hard to make an antenna that is better than a dipole." I like your antenna construction (seen on your QRZ.com page). - Cliff

[@bluesaloon22]

Thanks, Cliff. Yeah, every watt counts. I am a Foundation license holder and permitted a maximum power output of 10 watts. I've managed as far as Oregon to the west, Kazakhstan to the east and Argentina to the south. I like to point out to people that their refrigerator bulb puts out 15 watts. If you can't do it with 10 watts and a dipole you probably won't do it with 100 watts and the same dipole. :) Best wishes from Scotland.

[@rubiconjnw]

Hey Cliff, I really enjoy your videos. FYI, regarding your golf ball antenna deployment system, the term we use in the maritime world for laying out line in a "series of S curves" as you described is flaking. Keep up the great videos. 73, de Jim

[@guitardzan5641]

Flake....Don't hockle!

[@hamradiocq]

That's a really good point about the light weight coax. If you've ever tried to hoist an inverted V up you appreciate light weight very much, especially a fiberglass pole or something like that. I get tangled in trees however which is a tough problem to solve.

[@thormusique]

A truly excellent explanation, thanks! I'm sold on it. It's an excellent portable antenna system.

[@QRPSchool]

It really is a well-engineered antenna for portable use. Thanks! - Cliff

[@NSNorfolk]

That is a great antenna ! I made one this summer which is 40-30 and 20M and is also my GO TO antenna. I also keep an end-fed with an Un-Un in the bag with the KX-3 but really like the performance of the linked dipole. Get it up 20 or 25' and it really performs !

[@QRPSchool]

Someone asked where to buy the wire-winders like I showed in the video (with my golf ball/fishing line). I got them from SOTABEAMS. You can find them here: www.sotabeams.co.uk/midi-winders/

[@geod3589]

+QRP School LNR has something similar for $8..00, I use one to wind my endfed wire.

[@DennisMathias]

+George Smith George, how do you feel your endfed works. Good?

[@geod3589]

Dennis Mathias Hi Dennis. yes it works fb. I've used vertically and as a sloper, It is the 10/2/40 version and the SWR was good without any adjustment on all bands.

[@G4KDXlive]

Thank you for these informative videos. I use a few pieces of Sotabeams equipment here in the UK. I use their EFHW for 40, their Mountain tuner and various fibreglass masts which are just the job. The guy who owns the company sometimes takes stands in rallies here. I've subscribed to your channel and look forward to further videos. Main problem with hilltop operating in the UK is the weather - lots of wind and heavy rain which can get into the rig HI. 73, G4KDX.

[@QRPSchool]

Thank you for the kind words. I'm definitely a big fan of SOTABEAMS. Since I enjoy working portable, Richard has a number of particularly interesting toys for me. - Cliff

[@amanchester26]

GREAT VIDEO I OPERATE PRIMARILY PORTABLE IN NEW ENGLAND 12 MONTHS OUT OF THE YEAR. I HAVE MANY SOTABEAM ITEMS AND COULD NOT BE MORE HAPPY WITH THE PERFORMANCE OF MY DUAL BAND DIPOLE. THE CUSTOMER SERVICE IS PHENOMINAL ALSO...GREAT COMPANY !!!!

[@daviddietrich9449]

Well, Cliff, you have me sold! I am actively working on getting back into the hobby after being QRT for the last 6+ years (too much life in the way). All has changed. This nifty antenna I think will be my go-to dipole for field use (Buddipole for home most of the time). I am thinking about one of their end-fed wire antennas as well for those times when I don't want/can't set up a dipole, or I don't want to draw too much attention to my operation (at a city park). I am really enjoying your videos. I've been licensed since 2003 when I was 26. So, getting back into the hobby in my 40's is going to be great! I am a big QRP proponent and fan. DE KC9EHQ

[@QRPSchool]

Welcome back to the hobby, David! You're going to love that SOTABEAMS antenna, I promise. - Cliff

[@williamjordan6808]

Hi,Cliff great video i am not long into qrp,i love qrp,thankyou so much for your videos,like this antenna,73s from,William,N.Ireland.

[@QRPSchool]

+William Jordan Thank you, William. QRP is much more fun than firing up an amplifier and shooting fish in a barrel, I think! :-) -Cliff

[@barndweller4573]

I made one of these but I used paracord for strength and used Anderson Power pole connectors to link the wire together for each band. Mine heavier but mine covers 10,12,15,17,20,30,40 meters.

[@QRPSchool]

Anderson Power Poles are superior connectors, for sure! The aligator clips that SOTBEAMS use work great but they are prone to rusting if you use the antenna much. Of course, you can alway cut those aligator clips off and solder new ones on OR replace them with APP connectors. Congrats on building your own! - Cliff

[@morecambeanglersandtrawler1074]

Hi cliff can help me I purchased a home brew linked dipole at a ham feast in the uk. Looks so well made power pole links but I can’t work out the size or freq of it from feed point leg sizes are 15. 16. 9.10 9.1 inches total 49feet 11inch each side ?? Can you help

[@QRPSchool]

See the chart of dipole wire lengths after scroll down this page: www.n3fjp.com/antennas/dipoles.html Bear in mind that the height of the apex of the dipole can change the needed length. In other words, the length of wire needed for a particular band can change pretty dramatically if you’re deploying it at a lower height. If it was me, I’d put the apex of the antenna up at the height you expect to use it, and then connect it to an antenna analyzer to see the resonant frequencies. That’s a sure-fire way to determine what you’ve got. Of course, you can modify this antenna by adding or removing wire yourself. Enjoy the process! -Cliff

[@morecambeanglersandtrawler1074]

@@QRPSchool thank you I have tried to find the freq via linked dipole calculator but at these measurements it’s way off 25 ft for centre height it just dosnt had up and the make quality is very professional. Any way thank you

[@tomatkinson4616]

Cliff, thanks much. I have enough spare stuff I am going to build one of these. Your video is great, as with all of your's. Tom N2NUT

[@QRPSchool]

Tom Atkinson Thank you, Tom! -Cliff

[@MichaelLloyd]

SOTABeam makes really good stuff. I like the linked dipole. I just built and deployed a 20/40 trap dipole for Winter Field Day. 73 NE5U Mike

[@ColdestMoon_Channel]

Excellent video my friend. I love this antenna, I use it when ever I'm out /p and not using the vertical home-brew antenna. Good work 73 Dan (M0TGN)

[@QRPSchool]

+ColdestMoon Thanks, Dan!

[@daveys]

Good video, excellent quality. Richard (Sotabeams) stuff is pretty good. I suspect that his “kit” approach comes from his background in RF in very remote environments.

[@vk3crg]

Hi Cliff. Thanks for the video. I've just watched your review on the Sotabeams antenna and just ordered one. I have a Buddipole Deluxe and really like it but wanted to get a resonant antenna that would perform a little better as it's full size. 73 from Australia! Craig VK3CRG

[@QRPSchool]

Hello, Craig. I think you'll enjoy that SOTABEAMS linked dipole. You could certainly build one yourself, but you couldn't build it better! I hope to work you on the air someday. - Cliff

[@SkyCharter]

Nice review. Nice product. The only problem I see with the design is the wound-up RG-174 is subjected to a much smaller bend radius than it's designed to withstand.

[@OlivierDumont0]

Do you know what the typical effect would be of violating the minimum bend radius? Any pointers to better wire winders? thanks!

[@SkyCharter]

Typically there are two bend radius specifications for coax: bend it one-time and bend it over and over. The Belden "Type 8216" RG-174 equivalent only specifies one of these parameters at 1" leaving you to guess which type this is. Assuming the worst case, bend RG-174 tighter than 1 inch radius can break the copper plated steel center conductor strands. At least the stranding helps with the survivability, but bending takes its toll on coax and that's why bend radius is a coax cable specification. Here's some more info... www.picwire.com/technical/bend_radius.php A relatively round spool is the only thing I can think of to help mitigate tight bend radius during storage.

[@QRPSchool]

Hello, Olivier. I don't worry about it. If you are concerned, you could just toss the wire winder and coil the coax and secure it with velcro, etc. I've been using my SOTABeams antenna for quite a while and have noticed no issues. I figure if it ever fails, I could easily cut the coax and replace it. - Cliff p.s. This might be a good question for Richard Newstead of SOTABeams (and co-founder of the SOTA program!): www.sotabeams.co.uk/contact-us/

[@deannorris7005]

Very nice video and antenna.

[@alanread6596]

Excellent video very informative. 73's Alan in the UK.

[@kevinokeefe7796]

I just received mine in the mail Hoping it tougher then it looks

[@timg5tm941]

Hi cliff great video. Two queries:1. Can you use the 20m version as a sloping dipole from a tree down to the ground so just one half of the v? 2. If I use a drive on mast plate (steel) and then fit the 10m fibre glass pole on to that would it interfere electrically with an inverted v dipole as per your film? Kind regards Tim

[@QRPSchool]

1. Interesting question. I've never heard of anyone using only one side of a dipole as a vertical radiating element with the other end on the ground as a counterpoise. I wouldn't expect it to work very well. For a 1/4 wave radiator, you'd like to have a better ground system than just a single 1/4 radial. The weatherproof construction of the SOTABEAMS dipole makes it impossible to get to the ground side of the antenna without hacking it in some way. I actually think this is well worth thinking about. With the lower radiation angle of a vertical, it would be pretty cool to be able to make a convertible antenna by clipping on a few more 1/4 wave radial wires on the Ground side of the antenna and raising only the wire connected to the center conductor of the coax. Hmmm... I may explore this! However, you can certainly use the antenna as a traditional "sloper". If you've got room to deploy the entire length of the wire/rope on the lower side, the 20m portion will still be fairly high in the air. 2. You've have no problem with a drive-on steel base for your fiberglass mast. You don't want the antenna wires to be too close to anything metal so you'd want the wires to come down away from the metal body of the car. I deploy mine like this all the time with no problem whatsover. Go for it! - Cliff

[@N2LRB]

Thank you for the video. It's good to see products displayed before purchasing them. My only concern with this linked dipole is the bends in the coax. My fear would be of breaking the cooper inside or breaking the braid. Would it not be better to form it in a circle? Again thanks for the video. 73 from N2LRB.

[@QRPSchool]

+N2LRB It would be better to form the coax into a circle. You could do this and then use a piece of velcro to keep it from unrolling. It wouldn't all fit back into the pouch it come with but the antenna part could. I haven't really considered the winding of the RG-174 to be a weakness but I can see how you (and others) might. It may be more of a problem in theory than in reality. If my coax ever goes bad, I'll just cut it at the top near the center insulator and solder on a new connector. From that point on, I'd bring my own coax to connect to the new connector. That's a thought, if you wanted to modify the antenna BEFORE it has a chance to break. Thanks for writing! - Cliff

[@timmcdonough8543]

The RG-174 I've used has a stranded center conductor so I think as long as you don't wrap it really tightly it would be fine.

[@chrisf1165]

just ordered mine.. thanks for the tip. now I just need to find a golf ball. -N3MLB

[@clems6989]

Awesome Design. !

[@ea6wu]

Thanks for the video !

[@marcinmichigan2772]

what gauge wire is used in this antenna? I guess one drawback is that you always need the space required for 40m antenna when using it as a 20m antenna? Nice video, TY

[@QRPSchool]

marc hutchins The wire is quite thin... approximately 22 gauge. When deployed for 20m, you can cheat a bit on the total length by not unwinding the full length of wire on the 40m segment... making it the same length as if you were deploying a stand-alone 20m dipole. -Cliff

[@walshgeo]

Great video thanks for the info. I would like to try this antenna with a fiberglass telescopic mast. What length mast would you recommend? 73 George KB3WAQ

[@QRPSchool]

George, I would normally suggest you try to get a dipole antenna raised to 1/2 wavelength for a low radiation takeoff angle (better DX). That would be about 33 feet for the 20m band, for example. However, my understanding is that these SOTABEAM antennas are cut/trimmed for best SWR at about 7 meters or 23 feet. People doing SOTA activities are typically not deploying antennas at full height. So, I've removed the flimsiest couple of sections of my fiberglass masts and deploy the antennas at 20 to 25 feet. Have fun out there! - Cliff

[@walshgeo]

@@QRPSchool Cliff Thanks .George

[@Andre-PY4DR]

At 8:30 you show that the dipole is linked directly to the coaxial... no balun... and thats my question... Is it ok to use it with no balun? do you recomend using one... or not? and why? strong 73 de PU4ALZ :)

[@QRPSchool]

+Andre Nomad Hello, Andre. A dipole antenna, which is a balanced antenna, should theoretically use a balun when connecting to coax, which is an unbalance feed line. However, dipoles work fine without them. Technically, the braid of the coax is connected to one side of the dipole and will radiate RF... which could lead to stray RF in your ham shack. That said, I have a fan dipole here at my house without a balun and I'm not having any problems. I recommend using a balun to connect coax to a dipole if you have a balun. But, if you don't have a balun, you'll probably be okay without it... especially if you're outdoors working portable. - Cliff

[@Andre-PY4DR]

+QRP School Cliff, thank you so much for your attention.... It will be used with a transceiver made out of junk so having it damaged wouldnt be a big deal as having a kx3 damaged... haha (so far the total cost of the project is 5 cents) My fear though is that if i have RF coming back in the cable then i would have a significant loss of power (a friend told me that). And since QRP already is low power, i assume i should avoid any extra possible loss. What do you know about it?! was my friend right or he was just another one saying too much of a thing he knows too little?

[@QRPSchool]

+Andre Nomad Don't worry. Your friend is confused. Using a dipole without a Balun will NOT cause your radio to reduce its power output. There are 3 possible problems that baluns are supposed to solve: 1) the distortion of the radiation pattern of the antenna caused by the shield of the coax acting as part of the antenna. 2) TVI - the RF radiation from the coax coupling with household wiring, television sets, etc. and 3) RF energy coming into the ham shack due to the proximity of a live, radiating element (the coax shield). - Cliff

[@glennblanchard8805]

Go to Lowes and buy a 1/2" diameter wooden dowel, about 36" Sharpen one end of the dowel. Carry it with you in the field, it weighs nothing. Pound it into the ground and slip your fiberglass pole over it. Sorted.

[@eltayebabdalla1063]

very nice

[@DennisMathias]

That center feed point still bothers me. You're feeding an unbalanced coax to a balanced antenna. And then the possible Z mismatch depending on your configuration. So, your assignment (:-)) is to show us how you put this up..the next time you're in Bonaire or wherever it is you hang out..and get one of the antenna analyzers and demonstrate. Also, what do you do if no trees..Pole or what's your preference? Excellent videos you produce, BTW. You ought to get hired by the ARRL as a presenter!

[@QRPSchool]

+Dennis Mathias Hello, Dennis! Someone else asked about the need for a balun and this is what I said to him... "There are 3 possible problems that baluns are supposed to solve: 1) the distortion of the radiation pattern of the antenna caused by the shield of the coax acting as part of the antenna. 2) TVI - the RF radiation from the coax coupling with household wiring, television sets, etc. and 3) RF energy coming into the ham shack due to the proximity of a live, radiating element (the coax shield)." The height of the antenna, the way it's deployed (flat-top, inverted vee, sloper), and anything nearby that affects capacitance, etc., can all cause the SWR to be different than it was when the antenna was first cut/tuned. I think it's good to worry about such things a little... to acknowledge their existence... but not to dwell on it. After all, even with a 2:1 SWR, your signal will be down only 3db on the receiving side... that's only 1/2 of an S-Unit! As to how I deploy it... I have a golf ball with a screw eye and fishing line tied to the screw eye. I toss the golf ball over a tree branch and then tie the antenna to the fishing line (I actually use a snap swivel to make it easier). I then hoist the antenna up and operate. If I have no trees, I'll use a fiberglass telescopic mast and raise the dipole on the mast OR I'll use my telescopic vertical (see that video). - Cliff

[@DennisMathias]

+QRP School I did read that but it still got my attention. Really if we were doing it right we'd generate a field diagram via monitoring points and tune for max smoke no matter how the antenna is fed. But as with any antenna, if it radiates, who the hell cares. After all a dummy load is Puuurrrrrrfect. 1:1 VSWR. Perfect match. But it doesn't radiate. I think part of the run of coax is going to be radiating though without a match at the feed point. I should try a comparison of that someday. My experience is that there is a whole lot less RFI in the shack if there's a matching balun at the feedpoint. Outdoors, up on a hill..not so important.

[@QRPSchool]

+Dennis Mathias I think you're on to something, here. The way to do it "right" would be to fly a drone around the perimeter of the transmitting site, with the drone transmitting field strength readings in real-time. That way, we'd get a better understanding of the radiation pattern! Okay, that's crazy but I would absolutely do it if I had the technology! What fun! :-) "My experience is that there is a whole lot less RFI in the shack if there's a matching balun at the feedpoint." I'm sure you're right. I have a "choke balun" at the base of my vertical and I haven't had any problems. Fortunately, I haven't had any trouble with my multi-band dipole (that doesn't have a balun) causing RFI issues in the shack. Maybe if I was running more power (I don't own an amplifier) it would bite me. - Cliff

[@hamradiocq]

Making those wire winders and insulators...is a good reason to get a 3d printer.... : ) someday. : )

[@hamradiocq]

+AnythingWithWheels ....ugh, sorry I tried to comment to your comment and I accidentally hit "report spam or abuse" I don't see a way to undo that now.... sorry. Love your videos, keep them coming.

[@RobBob555]

3d printers are shite

[@donselbe5812]

This is similar to one I built in 1982

[@gautealarsen2580]

Thanks for the video! 73 de LA2BSA

[@warplanner8852]

Cliff, your videos evangelizing QRP are great but I would like to comment that the coax on the SOTABeam antennas might be a little flimsy for repeated use. I realize the point you made re losses, etc. but in the rough and tumble world of SOTA deployment, I'd sure appreciate something with a little more fortitude. Just sayin'.

[@nateo200]

That and in QRP with something like an 817 or 818ND that 2.5-5watts needs to radiate at maximum efficiency which means as low a VSWR as possible, the best antenna design (easy with a dipole and effort) and even low loss coax. The portable dipoles I've made, I left the middle a BNC connector for a lightweight coax or a bit heavier coax depending on the situation

[@planetowens]

Cliff: I've ordered my Sota beams dipole and some winders. I agree the winders are very unique. I like the ability to change to the other ban and not need the tuner. I think I'm going to use my Spiderbeams pole but might be a little too tall but I'll figure out a way to make it work. Thanks for the great videos! Michael KM4CBZ

[@QRPSchool]

Great, Michael! I think you're going to have a lot of fun with that antenna! - Cliff

[@planetowens]

Cliff: I received mine and the extra winders. I can't say enough good things about this thing. The SWR's were spot on 1:1 on both 20 and 40m. I'm using a 12m Spiderbeam pole but I just zip tie it at the 6m position and it works great. So fast to go up and take down too. I will be getting a smaller packable pole soon. Thanks for all your hard work. I really enjoy your QRP School. Your work is greatly appreciated here.

[@allanthompson9695]

Great Review. 73 G1JXI

[@kevinokeefe7796]

If I look at DX Engineering it says they come with a high performance balun. I did not see or hear you mention that in the video. Are they calling the center connection a balun or am I not understanding something Thanks for any help

[@QRPSchool]

Kevin OKeefe Mine is an older model and did not include the balun. A balun is not required but it’s nice to have. It converts the BALanced dipole to an UNbalanced coaxial cable, stopping the shield of the coax from radiating a signal. Scroll down and read the description of this item on the SOTABEAMS website: www.sotabeams.co.uk/antenna-centre-1-1-balun/

[@imscuba]

Just remember, any time you use a 50 Ohm to 50 Ohm adapter, THAT adaptation has loss too. Can be measured with a Spectrum Analyzer with a tracking generator & frequency of use. My advice is never adapt and keep all your radios uniform for field use, if BNC @ the radio , use BNC from the antenna. If N use N, never adapt. I prefer N as its water tight. UHF and BNC are NOT.

[@QRPSchool]

The loss you're referring to is "insertion loss" and there is a long-standing myth about this. At most, you'll lose .1dB with each adapter. Bear in mind that 3dB is a loss of half your power and 6dB is one S-Unit. So, if you had 30 adapters in a row, your signal might be 1/2 an S-Unit weaker. This is not something to worry about. I do have a Spectrum Analyzer with a tracking generator and could demonstrate this. As for water-tight connections, if I'm using any connector in the field that might encounter rain or dew, I always wrap the connection in self-fusing rubber tape. If the connection is going to be in the sun for many days, I'll wrap THAT with UV-resistant electrical tape.

[@WA8QFE]

I'm sorry, but the attempts I made with RG=174 were all failures ! I put up with weight of RG8x and have QRP DXCC from National Forests ! Lee, WA8QFE

[@RobBob555]

a dipole is balanced, coax is not.. there is no balun here so there will be an impedance mismatch.

[@VE3IPS]

Links????

[@paganphil100]

John Leonardelli: Link below. www.sotabeams.co.uk/