How to Build and Tune a Linked Dipole Antenna

I take you through my steps to build this 20 meter-30 meter-40 meter linked dipole antenna, including construction of the insulators, and a trip into the back yard to tune it up. I've built quite a number of these antennas and have strictly use them in the field for SOTA for many years. This is a great antenna to use for portable ops like Summits on the Air, Parks on the Air, or similar events. They perform quite well. The one I constructed only weighs 8 oz. It is best suited for QRP. I'm not sure how well it would perform above 20 watts.
Twitter: @NJ7V_
Instagram: RedSummitRF
Inverted-V Dipole Calculator: www.hamuniverse.com/dipivcal.html
Linked Dipole Calculator: www.sotamaps.org/extras
Knife Connectors: www.aircraftspruce.com/catalo...
Spade Connectors: amzn.to/39kudUd
BNC Connectors: amzn.to/3owOzQ2
22 Gauge Wire: amzn.to/3nzMXUP
Heat Shrink: amzn.to/3nzMXUP
My Favorite Coax Source: rfconnection.com/ I usually just ask them to add the BNC to one end for me. It's worth the extra cost to me.

[@MichaelLitty]

I'm a new ham learning so I can build my first HF antenna. The whole balun/unun thing has been overwhelming. This video gives me the confidence that I can build a basic dipole and at least get on the air. Thanks.

[@RedSummitRF]

Thanks for this. I have to agree about the balun stuff. It can be intimidating sometimes. Let me know how it goes!

[@barndweller4573]

Very cool thank you for doing the video. I love your idea for insulators! 88 cents for all you will need what a bargain! I built a linked dipole last weekend. Its for 10, 12,15,17,20,30,40 and I got under 1.8 swr across all the bands. I want to use it for POTA. I did it different. I got some small silicone coated wire its very very flexible. I taped it onto some paracord the entire way and did my connections with Anderson Power Pole Connectors. I was worried about stretching the wire if it had to support its own weight. It coils up really easy (I used an extension cord coiler). I hope to take it out and try it out this weekend. It takes like 1 min to change bands, I have a pully on the top of my pole and I just let down the center plug or unplug what ever I need to do and pull it back up. Thank you again for taking the time to make the video I am ripping off your idea for insulators and especially the center part, my God what they want for an insulator now is just nuts!

[@RedSummitRF]

Hi there - sounds like you have a fantastic antenna ready to go! Very nice! Please feel free to steal any of my ideas. The fact is I have very few original ideas and have barrowed them as well - haha!

[@netfixr1]

One of the best linked dipoles I've seen to date - Outstanding build quality & construction techniques -- Thanks for this video!!

[@RedSummitRF]

Hi Steve - first of all, thank you for visiting my channel. I also appreciate the feedback and I'm very pleased that you got value out of the video. This is why I make them. 73 Charlie NJ7V

[@bradleyjohnson452]

I just picked up a 857D. I need to make one of these for a first antenna. Thank you for sharing

[@RedSummitRF]

That's great! The 857D is a fantastic radio. I'm sure you'll love it. Thanks for your comments.

[@linlee7677]

Good step by step explination Charlie. I'll keep this one in mind for the Thursday Night New Hams Net.

[@RedSummitRF]

Thanks Lin and Lee 👍

[@ei9ju]

If you can do another video with that buddistick at the beach beside the saltwater, string the 20m dipole up too if your lucky enough to find tie-off points the do comparisons. Keep up the good work with the videos.

[@RedSummitRF]

That sounds like a fun day at the beach! Not in the plans anytime soon but it would be a great experiment, I agree!

[@K5ATA]

Great video, Charlie! I've been bitten by the antenna bug, so I am glad to have seen this one while playing catch up on some videos I've missed lately.

[@RedSummitRF]

Hi Steve - hey there! Thanks man. Yeah antenna builds are really fun! GL 👍

[@TheSmokinApe]

Somehow I missed this one, great job on the build Red.

[@RedSummitRF]

Thank you sir! I appreciate the support from you and the other guys!

[@BlessedLaymanNC]

Great video! Great idea. I love the material you found for spacers. I'll have to use them myself. I love how you locked the wires in and used the lugs for the connectors. I even love the way you wrapped the antenna. But, that ultra thin coax scares me, LOL! I'll definitely be stealing that cutting board insulators idea!

[@RedSummitRF]

hahaha thanks for the compliments. Don't let that coax scare you. This is the 3rd dipole I've made with it. None of those dipoles ever failed because of the coax. I've even tripped over it before and it was still just fine. The coax actually came out of the connector and so I just attached another and all was good. Good luck with the build. 73

[@pakeck1]

Very clear explanation, thanks

[@RedSummitRF]

Thank you Paul!

[@dwayneschank5456]

Thanks for the video I'm going to copy this but with a little bit bigger wire for a little more power. Thanks again great video!!!!

[@RedSummitRF]

Thanks Dwayne. Sounds good. I hope it goes well. Good luck.

[@Blue-Collar-Radio]

Great build and video! Tuning antennas is without a doubt my least favorite part of antenna building! I do think I need to build a linked dipole in my near future.

[@RedSummitRF]

Tuning can be a PITA for sure! Especially if you cut too short LOL 😬

[@dongibbskk4qam]

Nice video Red. You make it look easy. 73.

[@RedSummitRF]

Thanks Don - we both know it IS easy for you LOL. I appreciate how you support me everywhere I appear haha. BTW that was a great interview on AD6DM's podcast.

[@KK6USYHamRadioAdventures]

Nice job Charlie , thanks for sharing, I did a 40-20-10 they work great!

[@RedSummitRF]

Hey Chuck - you know it! My preferred choice. Thanks.

[@LU8HRW]

KK6USY, can works in 15M too? 73

[@KK6USYHamRadioAdventures]

@@LU8HRW yes if your careful cutting 40m you may get 15m also or you can cut a link for 15m

[@TheShawna1]

The only difference i do is use a BNC to Banana plug assembly as the center feed point Can use standard BNCs on both ends of the coax! and my connectors are single power pole connectors Black for 20M, Red for 30M, green for 40M, blue for 60M, and yellow for 80 meters...also no separating end just the legs zip tied together with the connection dangling about 2 inches each ready to be connected when needed.nice video tnks.73'jim KB1PFL

[@RedSummitRF]

Oh, very nice. Those are all smart improvements.

[@TheFossilChannel]

ive been using them as well and as it turns out the length i cut for the dipole tunes well with my 49:1 auto transformer so I can deploy with a dipole or a endfedhw sloper which increases my versatility in the field. great job!

[@RedSummitRF]

Indeed! These are great for the field. EFHW too.

[@richylad]

Nice Video, I did this yesterday and I tuned my 20m section and added the others like you, but when I went back to check the 20m the resonance had moved, so I think the 30 and 40M sections may affect the 20m slightly, like has been said tuning antennae can be a PITA, I am learning morse code so I have been watching your other vids,73 from the UK

[@RedSummitRF]

Yes. It's hard to say what happened there with the tuning. I try to keep the angle at the apex the same throughout. It means using a long rope for the higher frequencies and keeping the two end points fixed and tied throughout the tuning. Not saying that's it, just pointing out this is one of a myriad of little things that can affect the resonance. I hope you can get it dialed in. Good luck.

[@KB1HQS]

Thanks for sharing. Your intro reminds me of Black Mirror ;)

[@RedSummitRF]

I love that show and now that you mention it . . . it does!! haha

[@W0KNI]

Love the step-by-step, no nonsense instruction video you created. Great job sir! W0KNI. Sub+Like

[@RedSummitRF]

Hi Stephen - thanks for the compliment and the Sub+like. You have a great channel too.

[@shawnp6653]

Vert cool! I appreciate the understandable explanations and keeping everything in view of the camera. Thanks for sharing!

[@RedSummitRF]

Thanks Shawn. I appreciate you visiting the channel. 73

[@AA0Z]

Great video Red. It's funny how those cutting boards seem to always have a use in ham radio. I've used bullet connectors in the past, but I'll have to look up those knife connectors.

[@RedSummitRF]

Thanks Kyle - yeah cutting boards do the trick quite often. Bullet connectors are a good choice. I wish Adam's quick tip video would have come out earlier. I would have used his idea.

[@AA0Z]

@@RedSummitRF Yeah, really! Adam sitting on that tip really put a kink in all of our linked dipoles that we just made!

[@RedSummitRF]

😂 exactly

[@AD6DMDennis]

I wish I had all your workshop tools.

[@RedSummitRF]

Haha I thought my shop was marginal but I guess it depends on where you're coming from 🤔. Thanks Dennis.

[@DanielWiley]

Great Video! de N9BAV

[@RedSummitRF]

Thanks Daniel! 👍 73

[@Tom_2E1FUE]

Can you do a video on making a trapped dipole too, still not had time to build a linked one yet but I will in lock down.

[@RedSummitRF]

Sucks about the lock down. I see signs of another one here in the USA too. Thanks for your comment and request. I do have to say though, I don't think I could do it better than my friend K6ARK. He has a two part video on tapped dipoles. You can find them here: kzbin.info/www/bejne/qV7CfayemayUpq8 kzbin.info/www/bejne/Y6LJdISKj7h8q9U Thanks for watching 73

[@n1rbd]

I have that same Glock mat. :)

[@RedSummitRF]

Haha yeet!

[@walshgeo]

Charlie, Great video! What size mast do you use and how high is it deployed? 73 George KB3WAQ

[@RedSummitRF]

Hi George and thanks. It's a 20' Black Widow fishing pole. I don't use the last section so it is 17' high.

[@walshgeo]

@@RedSummitRF Charlie, Thanks. George KB3WAQ

[@brianve7jyd943]

Nicely done Charlie - good tutorial -- wud you be able to tell me - what MFJ analyser you where usoing - 73 Sir VE7JYD

[@RedSummitRF]

Hi Brian - I have a refurbished 259C. It may not be in production anymore. I got it for fairly inexpensive and works fine for me.

[@brianve7jyd943]

@@RedSummitRF thanks Charlie - they have the 259 D now very similar looking - $438 Canadian jus have to decide if ill make enuff antennas to warrant the cost - thanks for the reply 73

[@Tom_2E1FUE]

Might have to try this one can I use RG58 on the main line to the wires on the centre to the wires :)

[@RedSummitRF]

Hi Tom - thanks for watching. Yes, RG58 will work well and offer less loss. I use the RG174 to reduce weight but it's a compromise with loss. Good luck on the build!

[@45auto]

@@RedSummitRF Would the Black Widow pole handle the added weight of the RG58 (everything else being the same)?

[@RedSummitRF]

@@45auto I believe it would. I've used it with and antenna that had an RG58 feedline before. Didn't encounter any issues. That's why I like it. Yes, the length is a bit unwieldy collapsed, but it is more sturdy than any other I've purchased.

[@JayN4GO]

Charlie do you recommend 22awg? I was looking at 18 but it may get too bulky.

[@RedSummitRF]

Hi Jay - yes I used 18awg for this build and 3-4 others and have had no problem with it. I can see how some might argue that it is too bulky. I have made this design with 18, 22, and 26 awg. I think it's personal preference on that. 18 is good for me because I can be like a bull in a China shop when putting it up and taking it down sometimes. But for my ultra-light kit with the MTR3b I have the 26awg and just deploy a little more cautiously. So if you are liking the idea of 22 I'd say go for it!

[@JosephVE3GKT]

Charlie, I normally use spade connectors for my antennas I find them a little flimsy on stiff connections, and it's annoying to adjust the tightness just right. I am considering a change to either bullet connectors or the knife connectors you have shown above. Any fresh thoughts after 18 months? 73 de VE3GKT

[@RedSummitRF]

I would say go with the bullet connector. After some experience using these knife connectors I don't like them as much. They are a pain.

[@JosephVE3GKT]

@@RedSummitRF well... I'm very glad I asked! I'll do that. Thanks again!

[@o2bnov0307]

I need one of these for 20m/40m. Going to watch & watch. Are there some specifics that might help me? It'll be my first attempt.

[@RedSummitRF]

I think my advice would be that you don't have to do it the way I did. As long as the wire is cut to the right lengths you can make it the way you like, according to what supplies you can source. Banana plus Anderson power poles, aligator clips, I've seen it all for the connectors. Same is true for the cutting board. I've seen, clip boards, random plastic, wood, PCB. Have fun!

[@o2bnov0307]

@@RedSummitRF I still have not built the antenna. I ordered the center piece I'll use a SO-239 to BNC adapter, so I can use my QRP coax. I am really hesitant to but the wires, because my measurements are very different from you. Will you lend me some advice, please? Wire 1 - 33.12 ft. (17.19 ft per leg) Wire 2 - 33.12 ft. (15.93 ft per leg). Mast height -23 ft. Wire #1 is for 20m, and wire #2 is for 40m. Thank you.

[@davidryeburn8263]

Nice details. But why don't you use a 1:1 current balun at the center?

[@RedSummitRF]

It's not needed for QRP. Just unnecessary weight.

[@davidryeburn8263]

@@RedSummitRF Sure, you're not going to get RF burns despite its absence. And most SOTA sites are pretty quiet (unless there's someone else's big antenna nearby!) so picking up local noise on the coax that might make it difficult for you to hear weak signals won't be a problem, the way it can be in the city. But your linked dipole is probably a more efficient radiator than the outside of the coax braid so you might get higher signal reports from the people you contact if all your RF stays up in the antenna rather than some of it coming back down the outside of the coax. An FT50-43 toroid weighs 2 g and 10 or 15 bifilar turns of enamelled wire weigh next to nothing so I don't see how weight matters. Even an FT240-43 only weighs 118 g but you don't need such monsters for QRP. David VE7EZM and AF7BZ

[@RedSummitRF]

Vary good points. Thank you for offering them (including the parts info). Some who build the antenna may want to add the balun which would not be much more effort. The logic is sound, but personally I wouldn't do it for my set of circumstances. I've been very happy with the performance of the antenna without it. Maybe it's just personal preference as to which compromises in the system a person is willing to accept? This 1:1 balun thing is actually a debate that rages across ham forums. Some may like to add it. I'm happy without it. Isn't it wonderful that we have options and can make our own choices in the hobby based on both science and experience?

[@AndrewMurphy8383]

spruce is a supplier of parts for some one who scratch build real aircraft

[@RedSummitRF]

Oh ok. Didn't know. I found out about these from a pilot friend who made his plane form scratch. Makes sense, Thanks for watching.

[@aaronbenns9051]

I know theres math to make your antenna jive with certain bands but if you build it with a certain band in mind wont anything lower in frequency just fall in line ?

[@RedSummitRF]

I'm not sure I understand the question. I'll try ... without using a tuner with the radio and antenna, a dipole antenna will have to be cut to a frequency. SWR will be best there and as you move away from that center frequency the SWR gets worse. Some dipole antennas have broader range than others but not so broad as to perform on another band (other than something like the 40 and 15 bands). It all depends on the antenna design but this video is about dipoles so that's what I'm speaking to.

[@yoyomansteve]

So do you not need a balun or unun?

[@RedSummitRF]

Hi Steven - I guess for that one is up to you. My general rule of thumb is a balun/unun is not needed for QRP but should be used with higher power. Since I made this antenna for operating at 5 watts I saw no need to add one. I have been happy with the performance.

[@yoyomansteve]

@@RedSummitRF I am still learning about it all. I am planning on making one of these for during field day for POTA. I typically run 50 watts.

[@RedSummitRF]

I recommend adding a 1:1 balun then. I should probably do a video on that. You need a FT82-43 toroid (or something similar - the sizes do matter) and you will run the feedline (coax) through the toroid about 8 times. The instructions in this kit sort of show you how. www.sotabeams.co.uk/linked-dipole-portable-hf-antenna-kit/