DIY CB radio antenna, How to build a quarter wave vertical dipole CB antenna cheap

I have had four 102 inch whip antennas around for years, a friend gave me some 1 1/2" antenna mast, I paid $9 for the trucker mount, $17 for the coax and $18 for the chimney mount, I had the rest laying around the shop. Time to build a cheap CB base station antenna!

[@bobsbarnworkshop]

UPDATE! We've had some hellacious windstorms and the antenna still stands!

[@generalingwer4341]

Love all these home brew antennas that popped up here and there.thanks to you all,I have a cb sitten on my work bench today to repair.gave up on cb and communications work 25 years ago.now I'm making a return!!thank u all.

[@bobsbarnworkshop]

The best CB antenna I ever made was back when my house roof was asphalt shingles (I have steel now) I used the same base mount with a 102" ss whip antenna. I made a couple metal brackets and attached it right on the ridge of the roof, then I had attached four 102" wires to the base (ground) and stretched them down the roof slope at about 90 degrees to each other, 2 down each side of the roof and screwed them down. Then I ran a ground wire to a ground rod in the ground. It was fantastic! I could easily talk 10 miles with a 4-5W unmodified base station! Thanks for watching! Good luck in all your endeavors!

[@bobsbarnworkshop]

One note: when I drilled the PVC pipe coupling holes with the coax in the pipe (at about 22:50), I actually did cut the coax and had to pull it all apart, so drill those holes when the coax is OUT!

[@scorpiodrg]

Well that was going to be my question about the coax !! Thank for the video 📸

[@mikehamilton7206]

🤣🤣👍🏻

[@RC-Heli835]

Wow I have looked for this video many times again since I posted here 3 years ago and could not find it to save my life. I see now that it does not have the word whip in the Title.

[@bobsbarnworkshop]

Glad to have you back! I have almost 300 other DIY videos! Check them out! Thanks for watching!

[@bobsbarnworkshop]

SWR is about 1.2

[@porkyfedwell]

I'm also a ham. I made a vertical dipole also with the 102" whip, but with a non conductive mast, and for the second half of the dipole I just have a 102" piece of 10 gauge wire hanging down. Gravity does the rest.

[@bobsbarnworkshop]

porkyfedwell cool! Yeah a Dione is simple. One ham friend of mine said you could strip the jacket off the coax back 102” and turn it inside out back over the coax itself for 102” and hang that up vertical. Seems feasible. Thanks for your comments! I have 3 old SSB 𝐂B radios to recap and troubleshoot and tune up. I’m not a radio guy but I’ve been in EE for 35 years in industry so I think I can get it done!

[@porkyfedwell]

@@bobsbarnworkshop Sounds like you are more than qualified. You should just go ahead and get your ham ticket. These days it's a snap. No Morse code required. Although I only work Morse and not SSB or digital, myself. CB I have only in case of a national catastrophe such as the Carrington event or EMP, which might eliminate all local communications.

[@w.rustylane5650]

When tapping out new threads you need to cut a little then back it off to clean the cutting edge; do this until you get it completely tapped. If you don't back up a bit you run the risk of breaking the tap.

[@bobsbarnworkshop]

W. Rusty Lane yeah, I know, the pipe was very thin wall so not much worry of that!

[@robertmethia7080]

that's all good but hope you never get a lightning strike with an ungrounded antenna!

[@wr1million995]

You would've done so much better by placing the PVC at the base of the 102" whip, then used 1/4 wave radials made from guy wire attached to the ground bolts and insulated with parachute cord from 108" and down. Your SWR would be 1.1:1 or so and you'd have made the equivalent of a StarDuster, a vertically polarized 1/2 wave dipole. A straight dipole like this requires a coaxial choke at the base and is a 74ohm antenna by natural physics, so about 1.5:1 swr at best. Try it the other way and I bet you'll like it better, plus you should have less RFI getting into your audio with power.

[@bobsbarnworkshop]

W R 1 Million thanks for the input. One of my best friends is a HAM and I’ve heard all this info before. I’m just trying to make it as small unnoticeable and rugged to stand up to wind and weather. Years ago when my roof was asphalt, I used a similar mount and put the whip right on the ridge of the roof and stretched out 4 -102” ground radials from the screws into the mount. Very unnoticeable and rugged and I would have done it again but I have a steel roof so I figured it wouldn’t work that way.

[@porkyfedwell]

A ground plane vertical (what you're describing) is NOT the same as a vertical dipole. The efficiency of a vertical is highly dependent on the number of radials, while a vertical dipole is balanced. The most critical thing when constructing a vertical dipole is that the feedline leaves the dipole at a 90 degree angle to the antenna itself (i.e., feedline is horizontal while the antenna is vertical).

[@bobsbarnworkshop]

porkyfedwell I’m far from an antenna expert. Although I have a “factory” vertical dipole on my cottage, the coax screws into the bottom so I pretty much built this based on experience with that. My SWR is very low so I’m happy wit that! I built a roof mount antenna many years ago with the same type base for a 102” whip and put it right on the ridge of the roof with four 102” gr plane radials laying down the roof at 90 degree angles. That one had a barely detectable SWR! I got away with laying it right on the roof because it was wood with asphalt shingles, I now have steel shingles. Thanks for watching and commenting!

[@porkyfedwell]

@@bobsbarnworkshop Hi Bob. Actually I was not addressing you, but WR 1 million's post, as he didn't seem to understand the difference between a vertical ground plane antenna, and a vertical dipole. You have to be careful looking at SWR alone, since SWR has almost nothing to do with antenna efficiency (i.e., how well it radiates a signal). The perfect illustration of this is a 50 ohm dummy load, which has perfect SWR and is 0% efficient. Many other less extreme examples exist, of course. Best regards

[@bobsbarnworkshop]

porkyfedwell point well taken! I do know that the radiation pattern of a vertical dipole is far from ideal, like a donut! But I just wanted something that works, doesn’t blow my finals and is nearly invisible. Considering there is so little traffic anymore, I guess I’m good for now... I may try adding some horizontal ground radials to make it radiate more horizontal in the future. Thanks for the input!

[@justanotherguy3850]

This is done completely the hard way. All you need is a piece of schedule M and schedule L copper pipe with end caps. Drill out the end caps so that they hold a 3/8 by SO-239 socket and tighten it down. Slip the schedule M copper pipe over the schedule L and use machine screws to make them make electrical contact at the top. Use a 102 inch whip for the top and 102 in for the schedule M outer sleeve. The schedule L pipe should be about 3 ft longer to allow mounting. Run your RG8 up the center copper pipe and tighten it down to the SO-239 socket. This is when you put the machine screws in so that they create continuity between the pipes and the ring on the connector on the RG8. Use some foam pipe insulation and force it up between the schedule and the schedule L copper pipe at the bottom to keep them from making electrical contact. You now have what is called a coaxial sleeve antenna. What about nine RF course on the rg8 coax and hold them in place with adhesive shrink tube to minimize feed line radiation. I built one 15 years ago and it is still in perfect serve high in the mountains where we get snow and high winds every winter. I appreciate the fact that this individual made a video but he did it the hard way and a half wave dipole does not have 6db of gain. It is a unity gain antenna. This is the antenna of choice for Public Safety that continues to use low band as well as amateur radio operators hit run 6 meter repeaters. It is simple and cheap to build. Sorry to hijack your post but you really went about it the hard way. images.app.goo.gl/sSaxRwNqSKgJJyL17

[@bobsbarnworkshop]

I just used what I had laying around, so cost was $0... cooper pipe is expensive! I’m not saying that there’s many ways to make a better antenna, but free is free! Thanks for watching!

[@justanotherguy3850]

@@bobsbarnworkshop :: well, since you put it that way. Free is free. Cheap is cheap. As long as it works. But it doesn't have a 6dB gain. It's a zero gain. I appreciate the time you took to put the video together though. I didn't mean to come across as a dick either. My apologies. Anyone that takes the time to build their own antenna is good in my book. I'm an amateur extra class and I've been building them since I was 12 years old. To me, that's great enjoyment. Kudos to you. I don't know if you realized it but you showed people something that's more important than running a thousand Watts. That's having a good antenna. You can run 10 watts and make a contact that you can't make running a thousand Watts with a crappy antenna. Good on you.

[@bobsbarnworkshop]

So funny coincidence, I just sat down at the computer, switched on the old Lafayette telsat ssb 140 and talked to a guy 15 mikes away! First real contact I’ve made , so I guess it works

[@jackson4861]

Not long ago I mounted a 102 whip flat down tight against a metal pole barn roof with a 40x48 foot print using the entire roof as a ground plane. SWR flat from 26.0 to 28.0 then slowly climbs 1.1 down into 25 and up into 29. Broadest band coverage I’ve ever experienced, no spring just the 102 whip. I talk all over the lower 48 and up into Canada. I always get reports of loud and clear, and often accused of running power, the radio is so quiet sometimes I think it’s not on. Sweet deal for a $ 20 antenna.

[@bobsbarnworkshop]

Jack son nice! I always wondered if the steel roof was a good ground plane. Back when I had a shingle roof I used a whip right on the peak with four 102” ground radials at 90 degree increments laid down the slope, super low SWR on all channels. Thanks for watching!!!

[@jackson4861]

Bob's Barn Workshop How many ground radios did you use?

[@bobsbarnworkshop]

Jack son four 90 degrees apart, I used a truck mirror mount for the whip and drilled and tapped holes around the base to attach the radials. Soldered on eye terminals on each end of the radials and ran them down the slope of the roof and attached each down with a screw and a rubber grommet. It was nearly invisible and worked great

[@jackson4861]

Bob's Barn Workshop so two radials followed the roof peak opposite ways at 90’ and two slanted down over each side at 45’ ?

[@bobsbarnworkshop]

Jack son no, I sort of put them about 45 degrees off the ridge line so they all sloped at the same angle relative to the whip. Two down each side. Being a wooden roof with asphalt shingles it should be “invisible” to the radio signals. And I also ran a ground wire from the base mount of the whip to a ground rod just off the edge of the roof as close as I could get it

[@2e0wsj]

I would not use that plastic pipe all you need is a strong wind to snap I would have put some tape around the Pole then clamp it to the chimney

[@bobsbarnworkshop]

I added the plastic pipe coupling for two reasons, isolation of the lower part of the dipole and to add a lower section to raise the dipole up above my metal roof. It’s been up several years now and it’s holding up fine. Believe me, here in western NY we get plenty of high winds! Thanks for watching!

[@RC-Heli835]

I love this! How far have you gotten out on it? Just curious as to what the SWR's were like? Also was wondering if I could do the exact same thing except the short isolated metal pipe you have there Id like to be about a 30 ft metal pole going to the ground. Would there be any issues with that?😃

[@bobsbarnworkshop]

It's basically a 1/4 wave dipole (1/2 wave?), the 102" whip is the "hot element, and a 102" vertical pipe is the ground element. The coax goes up the center of the ground element eliminating the need to have the coax go out horizontal for a 1/4 wave.. Works good but hard to find anyone to talk to! My SWR is around 1.2

[@RC-Heli835]

@@bobsbarnworkshop All Tandem dump trucks and truckers have CBs. That's why I want a base so I can check my dump radio when theres no radio check close by. That's great on the SWRs.😀 I dont want to fool with radials if I dont have to.

[@bobsbarnworkshop]

The higher the better!

[@creativeretouching5746]

So, you did not make an antenna. Just mounted a 102" whip on a pole.

[@bobsbarnworkshop]

so I did "make an antenna" because the "pole" is actually the vertical ground plane of the antenna cut to 102" for CB frequencies.

[@kenoger2866]

Very nice work . Thorough and clean.

[@bobsbarnworkshop]

Watch part 2.....it works!

[@DustInTheWindAZ]

I know it's some 3 1/2 years later, but did you ever post a video documenting the results, even after replacing the coax? I'm considering such an antenna, since I live in a rental house (NOT an HOA) and want to minimize my antennas "footprint".

[@bobsbarnworkshop]

The antenna us still working fine, swr is below 1.5 on all channels. 1.2 on most. I don’t use it a lot but when I do it seems to perform well. Not much out there except “alligator” skip talkers….

[@washingtonstatepicker3460]

Nice drill

[@washingtonstatepicker3460]

Great idea on the antenna. So pipe is one end of the dipole, and the 102" whip is the other?

[@bobsbarnworkshop]

yep. simple and cheap. My HAM friend says the fatter ground element gives better "bandwidth"... audio frequency? I dunno!

[@johnyoung1128]

@@bobsbarnworkshop Thicker elements will give better bandwidth but will also be “electrically longer”which means a thicker element might have to be cut a little physically shorter to maintain resonance, this might become an issue when it comes to tuning up the antenna but if you say SWR is okay then there’s little need to worry.

[@bobsbarnworkshop]

@@johnyoung1128 thanks for the info, my career was in electronics but never got into radio and antenna theory much, just know the basics. My friend is a long time HAM so he gives me help and advice from time to time. Thanks for watching!

[@johnyoung1128]

@@bobsbarnworkshop Thanks, I am a long term amateur radio operator as well here in Australia (VK3YO although I’m not currently active) and I have made antenna design one of my interests. It’s good to see someone having a go at DIY. Unfortunately it’s a topic that tends to create argument. The design you have shown in your video is a sound one, your friend has given good advice.

[@bobsbarnworkshop]

@@johnyoung1128 years ago when my house roof was asphalt, I mounted a 102” whip on a base like the one I used on this one. I mounted it right on the peak ridge and drilled and tapped the base to attach four 102” wire radials and laid them down the slopes of the roof at 90 degree angles and attached the ends with rubber grommets to the roof. That design worked incredibly well! Super low SWR on all channels and I could reliably talk 10 miles with a standard 4W cb radio. Now my roof is steel so I can’t do that anymore. Thanks for your comments!

[@ITSHAA-yn5zc]

A Ham told you 6db of gain? No. 1/4 wave antenna is unity gain.

[@Ass_Burgers_Syndrome]

I had to laugh when I heard that bit

[@micro4329]

Could have just made the roof the ground element would be a bigger plane for the vertical

[@bobsbarnworkshop]

I thought about that but I wasn’t sure the metal shingles were connected together low impedance

[@AdamosDad]

Nice but why not U-bolt the bracket to the pipe.

[@bobsbarnworkshop]

AdamosDad because the way I wanted the coax up the center it would hit the inside of the pipe, so I needed to offset the mount with some washers so it didn’t hit

[@AdamosDad]

@@bobsbarnworkshop I meant a U-bolt like a muffler clamp. In any case you did a great job and gave me some ideas. I'm working out weather to build a 1/4 wave that I know would easily match up to the radio or take my chances with a higher gain 5/8 wave. The same antenna would be used on a cb as well as a ham rig.

[@bobsbarnworkshop]

@@AdamosDad right at the beginning where I try to show what I'm going to do, I do show some U bolt type clamps, but after I tapped the 1/4" holes the mount was so stiff I decided not to use them

[@Fareskhachan]

good job, but you have short antenna whit out coil for the 27 mhz ?

[@bobsbarnworkshop]

Well it seems to work, SWR is low and it was free! (I used materials I've had around for years!) So I'm good with that! Thanks for watching and your comment!

[@wewanttobefree41]

can I use a satellite? dish to make an antenna

[@wewanttobefree41]

why not just use the c clamps and I live in a subdivision with an HOA THEY SAY NO ANTENNAS BUT THEY HAVE Satellite dishes all over the place

[@mrmrlee]

@ 13:47 You could just drill through the pipe and use a bolt with nylon locknut on the other side, no worries about the bolt backing out of the threads. Much easier.

[@bobsbarnworkshop]

mrmrlee sounds like a good idea but won’t work in this design... the coax and connector are inside the pipe right where the bolts would be. Thanks for watching!

[@mrmrlee]

@@bobsbarnworkshop Hey you're right, glad you told me before I tried this! Looks like a fun build.

[@bobsbarnworkshop]

mrmrlee I suppose you could use U bolts around the outside. The mirror mount has 4 holes to accommodate them. The pipe I used was too large in diameter but I thought about using 1/4” threaded rod and bending it around to fit. Let me know how it turns out!

[@mrmrlee]

@@bobsbarnworkshop Will do, thanks!

[@rickvia8435]

OK - you built it (and took up way yonder too much time explaining the mechanical parts). How did the SWR match up with the 11M band and How good was it's performance?

[@bobsbarnworkshop]

Rick Via SWR is under 1.2 in all channels so I’m happy

[@rickvia8435]

@@bobsbarnworkshop Cool - looks like a good result to your project. Dipoles make the simplest most effective antennas. You put one up without having to have the feedline at a 90 degree, 1/4 wavelength offset. That's really cool.

[@bobsbarnworkshop]

Rick Via I have a similar fiberglass one at my cottage (I bought it used years ago) and the connector is on the bottom so I assumed there was coax up the middle, so I fashioned mine after it. Mine has better SWR!

[@rickvia8435]

@@bobsbarnworkshop I've had a couple of Antron 99s. There was also the old Shakespear "Big Stick - almost Identical. They're advertized as 1/2 wave collinears, but very well may be half-wave vertical dipoles.

[@bobsbarnworkshop]

Rick Via my house now has a steel roof so I couldn’t make one like I did when the roof was asphalt. I used a similar truck mount for the base of the whip and added some steel strips so I could screw it on the ridge of the roof. I then attached four 102” ground radials to tapped holes in the aluminum base and spread them out at 90 degree angles down the slope of the roof. It was literally an “invisible” antenna and SWR was nearly undetectable! Cheap too! A whip, a base and coax!

[@Michael-xl8dz]

No potbelly Spring? But looks Great !!!

[@bobsbarnworkshop]

Michael1212 just for fun and hobby use, it seems to work well especially for the price! Thanks

[@joerowland7350]

Whith out the spring it no 1/4 wave for 11 meters but it is for 10 meters put wrong length coax will give you a fouls swr reading all ways set swr right at the antenna n smell your silicon if smells like vinegar it will cose corosin it your coax connectors I'm not trying b rude I learned the hard way best way seill coax first wrap with electric tape from 3 in below going up then wrap whith coax seal it like soft tar then work it whith your hands till you can see the seams. 73 n9prf n good dx

[@maplelagoo9001]

Is there a "part two"?

[@bobsbarnworkshop]

yes

[@WillemHosking-lz7tx]

Hi how meny meter is it

[@bobsbarnworkshop]

@@WillemHosking-lz7tx 102 inch stainless whip, mast cut to 102 inches…, I don’t do meters

[@WillemHosking-lz7tx]

@@bobsbarnworkshop i mean the pole

[@bobsbarnworkshop]

@@WillemHosking-lz7tx the pvc section below the antenna is about 2 feet long, then another section of steel pipe on the bottom is about 4’. These lengths are unimportant and don’t affect the performance of the antenna. Just there for isolation and mounting. Good luck! Thanks for watching!

[@sleeve8651]

A resurgence of C.B. radio ? These are much different times ! Too many disrespectful foul mouthed local trash ! These are not the old days of Citizen Band Radio ! Society as a whole has changed ! Hell, even most Truckers have left C.B., as it got so bad ! Too many kooks running around, that will easily find your location ! You'd be crazy to take those chances, especially if you have a family ! Run away, don't walk !

[@scottrakes1622]

Do you want a little antenna to go with that caulk? 😂 Just giving you crap. Good job

[@bobsbarnworkshop]

Just trying to keep corrosion from killing my connections.... I can’t see it upon the roof!!! Ha ha!!! I talked to a guy 15 miles away on it a couple nights ago, do it’s still working!

[@bobsbarnworkshop]

Also, I did a second video testing this antenna and the highest SWR it had is less than 1.2 SWR on all channels!