Making and Using a Simple 40-m Dipole (#86) 

Dave, As I didn't hear you specify your splice in this video, I would suggest anyone who wishes to assemble a wire antenna from several pieces of wire to use the Linesman (AKA Western Union) Splice prior to soldering for best mechanical strength. Many RU-vid videos available to demonstrate how. Essentially the splice is twisting the two wires together 2-3 times, you then wind each free end in a tight coil around the standing length of the opposite wire. Pull both wires until splice is taut, then solder. As for soldering I prefer using an iron with a substantial tip for best thermal transfer, I've have good results with my 35+ year old Archer modular Iron with the 45W heater element and a 0.25" pyramid tip. It is a little too small for Coax braid to PL-259 shield soldering though.

Building an antenna from spare parts is definitely in the spirit of ham radio! So glad to see it was so successful! "73"

Thanks Dave info was great for me

We call it Twin and Earth in the UK.

I'm new to Ham so, take this for what it's worth. The antenna tester read 7.some odd MHz and you said that's the top of the band. My crappy little Baofeng reads 400 some odd MHz. Are we talking about the same MHz? Are we talking about radio frequencies? Big sign over my head reads, "Not Getting It"

I scanned the comments and didn't see it addressed. When splitting out Romex you don't need to cut the insulation all the way along the length. Once you get about 8" split out, just hold onto all of the wires with one hand, the outer sheathing with the other, and pull them. The wires will split the outer sheath all the way down as you pull. Saves a lot of time.

Thank you for this video, David! I am a new ham (just got General in February), and I just got a good HF radio. NOW I have to get an antenna up! This gave me a lot of good information. I really appreciate what you're doing. Thanks again!

Making something yourself from leftovers gives you better feelings than just pulling out the plastic cards. Moe K2JDM

A little note from my own experience. If you use insulated wire cut the wire at least 10 % longer than the formula for bare wire, due to velocity factor changes.

I slapped together a 20m "sloped delta" out of bailing wire a few nights ago, while waiting for the laundry to finish. For connections, since it's temporary, I used some wago blocks I had lying around. It's amazing how well it works for being literally $2 in parts (mostly the wago connectors, though that doesn't include the $600 antenna analyzer…). Antennas are one of my favorite parts of radio, so I'm looking forward to the rest of this series!

Hi Dave...love watching your videos 👍 I've never had a store-bought antenna. An old family friend from the 50's and 60's got me interested in shortwave and ham when I was just a kid. He had a shake full of surplus military Hallicrafters/Collins equipment. Lewis taught me how to solder, use a Simpson vom and make antenna's. Dad gave me a Simpson for Christmas which I still have and use to this day. Lewis also gave me a Hallicrafters S-40a...1948? I think? Anyway, to keep it I had to troubleshoot and repair, then log when I heard him on the air...He was K4BQS...Lewis gave me 100' of coax, with no connectors and I built my very first 20m HF dipole. We had lots of trees...that was 1964, I was 14...I was off and running and never forgot my radio roots...My entire life has been in communications thanks to one mans teaching! I'm old-school, nothing fancy. I have a very nice Yaesu FT-101B...I like the smell of tubes in the final...73's I thank you so much for your videos, I've got couple trees begging for an 80m antenna❕

To save you time, he has 3 pieces of wires that were connected together and split them. Jump to 7:31 onto the second step.

Brilliant video. Made me giggle when you said you nearly went and bought one .keep up the great videos 👍

The temptation to buy a pre made was quite strong. Yep, that's not uncommon at times. While there's some really well made gear out there i guess the down side is the practical experience and applying the theory is lost. Building any of this gear really educates fast. The great thing about radio hobby is people are very generous in helping others learn. It puzzles me how the pioneers worked all this out with very little resources on hand.

Good video but I just cringed watching you pull that Romex knife along the cable toward you along your arm. Never pull toward you. That's Knife Rule Number 2. ;-)

I am making the same antenna. However I bought a coil with the pl259 on it. I am not sure if it is a 49 to 1 or vice versa, but has strictly the number 49 on it. It will be an easy fix if the coil is a problem. Thanks for your video I still find it a great source for my endeavors 73 N6ZKI !

Hello David, ....question: suppose i want to receive the 6mhz band, so 468/6 = 78 feet, then my horizontal wire will be 39 feet each side, right? Ok, with that wire length , can I also receive all the frequencies over 6mhz? ....and no frequencies under? So for example, a dipole antenna at 78 feet would be good also for any frequencies over 6 mhz....but not for 5 mhz for example. Thank you for answering :).

Just wanted to say thank you. Your videos are the best on youtube for someone like me learning the essentials of amateur radio.

I think the audio issue is that the mic is being covered by your chin/neck when you drop your head down.

i would have enjoyed it if you showed the finished S0239 connecter on the 40 meter dipole. Is that what you only used to connect to the cable? thanks for your help KM4WMC. Enjoyed your video. I Made my first 40m contact

Pow. Pow pop. At 2:00 am . It all came down. Again. A 2" pipe was broken in the mid night pull down. Put it all up (again) and at 68 years old that was work. Seems I've got to pay for all the entertainment I get. What will the Vandal think of a fence charger??. Used mostly used for mw and 160 meters. Not a transmitter Ant . Best wishes stay well. Kv4li.

How did you put that up high? How high must it go? What did the numbers on your analyzer mean? Sorry...newbie...

Just a point.. No pun intended. Drawing the Shingle blade towards yourself parallel to you arm at 4:29 is looking for trouble. Many people have done serious damage by doing exactly that.

My 20 and 40 dipoles are my treasure, barefooting, I can reach Eastern Europe and the West Coast from Charleston, SC. With my EF8010, I can still reach the huge power contesters in Eastern Europe..but not so much the West Coast. Not quite as much power delivery, but I have all bands. It's a trade off. And the end fed gives me 80!

Having just gotten my General license and being on a tight budget , I found this very interesting and timely. One thing to try...I've stripped Romex in the past for other uses and found that if I started the cover to split I could usually take the wire in one hand and the cover in the other and just pull them apart and the cover would continue to split. I've watched and enjoyed many of your videos, please keep up the good work. 73 KG5OKG

Too bad you didn't have a tool for drawing the wire down. It'd give you a longer wire, while also reducing the diameter.

FYI black is not hot in U.K. Old UK (and possibly other EU countries) systems black was neutral and new systems black was dropped and blue is used for neutral.

Did you need to ground the wire? And you didn’t address what the top end looks like thanks Kc2duy 73

If your antenna gets struck by lighting, there's going to be more than solder that "goes away".

A big old soldering gun if you have one makes short work of soldering those heavier wires.

this is such a lovely video, i really like at how honest you are in your presentation, showing us the warts and all of creating an antenna from parts. the part about 'getting the card out' really inspired me to become more like that, and think about what i can do with what i have, or at least keeping the spend to minimum - an inspiring video from a great teacher :) 73's from M7ALU

I learned black is positive in tent campers as well.. 😂

Great video. I doing this project right now. My first home brew antenna for my bitx 40

Hi David, thanks for your video. I had the impression you were out of breath in several moments of the video. Please take care of your health.

I wish there were more close up shots. But great presentation anyways.

You use what you got and if it works then great! I did the same when I was a Novice (1986) recycled wire from construction projects around town that had to solder to make 5 bands for a fan dipole. I had a Radio Shack soldering iron and my Dad's old Weller soldering gun that he bought around the mid fifties. I quickly found the RS soldering iron didn't have enough heat to flow the solder. So, I agree with Steve about having a Weller in your toolkit. Glad your homebrew worked. About your 2 masts though. Do you think the 2 friction joints would hold up to extended use? Look forward to your tests of the commercial built antennas. 72 de Terry - KB8AMZ

This must have been his First antenna. I am surprised.

Is there a reason why you did not use a matching transformer?

$100 pre-made or less than $20 if you make it.....

Enjoyed it Dave! I'm going to get going on making a 10 M dipole soon

Great video Dave. Thanks and keep them coming. Your videos played a large part in my passing the extra exam. 73

Great video. Looking to DIY my first HF antenna upon completing the general and extra exams.

I've watched 86 videos in a row, and never has Dave explained where he got that black and blue circuit board holder device. Can someone please link to it on amazon or qsradio or somewhere? I'd like to grab one.

That is part of Ham Radio. Building antennas without spending money. I wish it was the same with 100w radios!

I remember that time of year when i lived in denver. The weather was pretty consistent!

Muchas gracias David por los conocimientos que compartes y los haces fáciles de entender sumado al buen carácter que demuestras. Saludos cordiales desde la Ciudad de México XE1YCH

Thank you for your help could I ask that you can make a video of the different antenna connectors of ham radios there so many I have a look at the one that you said thank you once again

Boy you need a100w iron.😂

Just getting started, on a shoestring budget, have a good "Elmer", ...........Now your videos are just the teaching tool needed! Sincerely, Captain BUCKLEY(ret.)

Dave, you mentioned that you were not going to add a Balun at the feed point initially. When would you "know" that you would need a Balun? What would tell you this fact? A really high SWR? Also, are Baluns rated for PEP power? In other words, would a Balun that is just fine for 100W PEP be not up to the task at 1000W PEP? Likewise the wire AWG? Great Video. Love your observations on the build. Art

Fairly new General here. For the fun of it, the learning experience and a general lack of money, I recently built a 40 meter dipole and deployed it for NVIS. This antenna was built for free using dog underground fence wire (solid and pretty thin) which I happened to have plenty of on hand, a piece of heat shrink tubing and 3 pieces of small diameter rope. My total cost for the antenna was free! I hooked this antenna to my recently built el cheapo radio (Pixie S) kit from amazon and both the antenna and radio are working great! I literally have less than $11 in (the cheapest that I could find) soldering iron with solder and $13.59 in the radio. I am ecstatic to be able to get on the 40 meters for less than $30 and maybe 5 hours of my time! Everyone has to start somewhere, I am starting at the bottom and so can virtually anyone else who truly wants to apply themselves!

14:08.....LOL.....I was literally thinking that EXACT thing 30 seconds before you said it. Just enough time that I was looking at the ready made antenna on my phone while still playing your video...and then heard you say that 😂😂😂

hello and wecome from wales uk love your series great presentation well done

It's been awhile since you built this antenna, but I wanted to comment anyway. I just wanted to mention that you have used some heat-shrink wrapping around the solder connections to avoid the sharp edges. It would also weather proof the solder joint and prevent corrosion from weakening the joints. Just my $0.02. 73 de AI4QX

your microphone problems made me smile as a famous english comedian called 'Jasper Carrot' done a sketch called 'microphones' where he experienced exactly the noise/sound quality issues you face. not used to have a giggle whilst learning from your great videos.

Hi getting ready to put up a Di pole. Roughly 65ft more or less. Replaces the one that came down at 2am. Too many new people thinking I'm causing hash. Showed my log book and dust on rig. Neighbor has his son helping me put the new one in place. Kv4li 73 ( his dad had a switch in his hand?)

It is fun to review your HF antenna videos now that I have an HF radio. I bough the IC-7300.

Dave always very informative videos..my 20m dipole was made from romax and works great right from the get go..it`s been up for over 3 years now and with only 100 watts on this old Icom 738 it gets great results from 12 ft. off the back of my deck to a tree...I live in Pgh. Pa. With that setup I have worked asia and all over europe when the conditions are running good...by the way the ends are soldered right to the coax..so far so good...keep up the great work you do..73 Bob

We are still getting good views and info out of your older videos. Been catching up. Nice Work David!

The blade was designed for carpet and tile cutting lol, but very adaptable for your application, great site thanks.

do you have parts list? I would like get those white insulators for the dipole you inspired me to make! Thanks 73!

I enjoyed your video I'm going to build your antenna I just bought an IC7200 for my 5 ton Military Truck thank Dave 73's

You never did show how to determine how much to shorten or lengthen the antenna to achieve resonances at the 40 meter band. I am sure you didn’t just wing it.

Always CUT TOWARDS UR BUDDY , NOT UR BODY OG

Very helpful to see both build and qso w/o balun. 73, K0VY

Great tutorials Dave. I tell all the new hams I know to check out your channel. Maybe you could do a video telling us about your career as an engineer. I bet you have lots of interesting stories. 73's

open it up grab the copper wire with pliers and pull while holding the plastic sleeve..

40 Meters my all time favorite band thanks again Dave for showing us how to build a dipole for 40 Meters. 73 KC9QVE Gas City,Indiana

No balun tho

There is no positive or negative in an AC circuit. There is a "HOT" and a "NEUTRAL". The neutral refers to the conductor that is locally bonded to ground.

Great video - scary thumbnail!

Great video Dave! How tall were your test poles? I’m thinking I can get a dipole 20’ off the ground, but that might be max. I’m hoping for all hope I can do some DX. I’m limited by some funding for a tower (kind of expensive) and by my wife. I really wish I could run about a half mile of cable to the radio station tower, but that might be expensive and they may frown upon it. Anyway I’m playing catch-up with videos as I’m a new tech, but loving it. -73- Kevin KC1KSM

Dave - As usual an interesting lesson & video. we are all getting old and less frisky. I'm wondering about RF safety, specifically safe distance from a radiating RF antenna. As I read FCC OET65, the safe distance from a 40 meter band antenna at 500W or less is 1/2 wavelength = 70 ft. I know very little about amateur radio. do these numbers seem right to you ? what is the typical amateur radio station broadcasting power ?

Great video for a guy 77 getting back into this hobby since 1985 !

Dave, surprised your antenna was that far off if it was 66 feet. Each side should be 234/Fmhz or, of course, 33 feet. I find that comes pretty close to somewhere inside the 40m band. If your original length was resonant at 6 Mhz, then it was about 38.5 feet on a side. In any event, if I am a Mhz or more low at HF, I cut 6 inches off each end and measure until the frequency falls within 250 Khz and then it's an inch at a time. Another way is to determine proportionally how much to cut or add by dividing the original measurement is to divide your center frequency by your **desired** center frequency. Bottom line is that **no ham** should buy a commercially made dipole until he makes at least one of his own. And then he will **never** buy one afterwards when he sees how much money he saves! 71/72 de k6whp dit dit

Very handy video. I hadn't thought about using Romex before. Hey Dave, I took a little trip today (Farmington, Hesperus, Dolores, Telluride, and then around the mountain thru Ridgeway, Ouray, Durango, Silverton, etc, and back to Farmington). Unfortunately I didn't have the repeater in your area programmed in and I didn't have the manual with me so I didn't get a chance to give you a call. I'll get up that way later this year and hopefully I'll be able to give you a call. 73 NE5U Mike

This answers a pretty big question of mine about HF antennas. Thanks OG \m/ PS: Some producers are gonna sample the heck out of this vid.

Hello dave thank u for brilliant video, qui ! What is good size for 100 watt in mm not on gauges ? 73

Just a couple of questions, what are you using as the support poles for your dipole? If converting it to an inverted dipole the length remains the same for each arm. Like the comment about not worrying about solder if lightning strikes, but do you have protection ? spark arrester /gap at the transmitter/ receiver end or ATU?

Fantastic video, I was looking to make a 40m dipole, now I know how to do it. Thank you!

This was a great help to me. I was given some coax and had some salvaged wire like yours to work with. The white plastic cutting boards sold at Sams club cut into strips make great insulators. I got it all put together and made my first HF contacts the other day. Thanks for the great instructional videos. W1CAW

Yes thank you Dave it is for hf I am using a diy virticle at the moment it's a cross between two old antennas

Dave, you could demonstrate how to use the 40m dipole on say 20m and or 10m by inserting an insulator part way along the dipole arms, its a pain when you want to change bands as it has to be lowered, but its certainly budget antenna de G zero FFL

As I watched this video, I thought, "okay, Dave, expect some dipoles from various companies in the mail... I should just ask him to forward them on to me". ;-) So, at the end when you mentioned the reason for this antenna (as I interpreted it) was to form a baseline to test store-bought dipoles and even a possible give-a-way, it brightened my evening. Certainly, for taking the time to make quality, enjoyable, and highly educational videos, you deserve whatever free merchandise you receive. Thank you for thinking of the rest of us viewers!

Hi Dave! I am back in Ham Radio after more then 15 years! I have to say your series are a solid motivation! Looking forward to work with you! 73 de DM1TX from Munich

Stop "bearding" your microphone.

Great video thank you sir! Love the concept of not having to go out and sling the cash/card around. Where can I find the formula for figuring up 1/2 wavelength for the different frequencies?

Hello dave I just getting in to ham radios I'm. Looking to get a yaseu ftdx5000 or a icom ic 7700 what would you recommend for antenna for the top of my house and why does the back of these ham radios that I said have more then one antenna connections thank you James

When you were slicing the Romex with that knife next to your arm, I winced. It looked like one slip would have opened up your forearm quite seriously.

Thanks for the awesome videos! The audio issue you mentioned at the beginning was your neck resting down over the mic when you were looking down. Clip the mic down on your shirt and not around your collar. Problem solved!

Thanks for this video. I'm really fascinated by the the price / complexity / performance trade-offs between simple wire antennas, verticals, and beams. I've got dipoles at home, and though I've never tried anything else, I've been happy with them. Curious to know how you think your testing rig at 20 feet will affect the performance of a 40m antenna. Have you modeled the pattern in NEC?

Cut away from yourself! Your making me cringe...I just see you slipping and going into your arm

Hi David.... really enjoying your antenna series of videos. Many thanks 73

What type of insulators? Where to buy? 73 de KI5CXO;

Another great video! BTW, LOL, I really like that tee-shirt!

David, thanks i enjoy your video. Regards from Chile!

Hmmmm.....no 1:1 balun ?? I thought that was a necessity. Silly me.

...That Home Depot wire was stranded...is there a better choice, stranded or solid ?

Thanks for the great video, as always. I kept think thinking about that scene from Futurama where the professor talks about the various length of wire he used when building his spaceship! (Meant as a compliment, it's one of my favorite shows.)

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