A J-pole antenna is different than a ground plane antenna. The longest side of the antenna is approx. 3/4 wavelengths tall and the short side approx. 1/4 wavelength (1 full wave total). The bottom section of this antenna not only radiates part of the signal, it also acts like a matching cable. Tuning impedance to match 50 ohms is done by moving the feed-point up or down between the two sides of the J shape antenna. Mounted at the same height it should outperform any 1/4, 1/2 or 5/8 wave antenna.
Hi Dave. Just wanted you to know that I followed your instructions and built this (my first) antenna. A true success. Used my little 5 watt HT to hit a 144.6 repeater 20miles away, and was heard all over my state. Reports back was "clear as a bell:. Many thanks.
Hi Dave, Jack Wa1ngh, I have built this Antenna 3 times over the last few years and what a great antenna it is. I have found that cutting the long side of the stub seems to work easier for tuning. Thanks for sharing that antenna, it has given me 100 plus countries on 10 meter. Grear Job! 73
My 1st 2 meter antenna was a shop bought "Slim Jim" which is similar in principle to a J-Pole except it has a folded full wave radiator. It had a lot of weather and reliability issues so has been banished into the garage for the past 25 years. I replaced it with a 3/4 wave ground plane monopole antenna which far out performed it and this antenna has been sat on a mast for 25 years now. This is simply an insulated copper wire PVC taped to a length of white plastic tubing and clamped to the mast with hose clips (We call them "Jubilee Clips" in the UK after the British company that invented them a long time ago). The same principle could be applied to create a cheap 104 Inch 1/4 wave antenna for CB radio. Back in my CB radio days in the UK, I ran a shop bought 5/8 wave antenna (4.5 dB gain) but then I built a 3/4 wave antenna (6.14 dB gain) using aluminium tubing. I had to double sleeve the lower 1/2 wave section as the 26 foot rod does whip around a lot when the wind blow, which is probably why the more practical but inferior 5/8 wave is more popular on HF bands. On VHF and UHF using a 5/8 wave when a 3/4 wave is just as practical just seems silly.
just wonderful video. at first i saw the time of video..length..but after 45 seconds, i knew i was gonna watch the entire show..thank you for your knowledge and willingness to share it.
Horizontally polarized antennas are generally sky wave antennas. The simplest is a dipole antenna mounted horizontally. For the CB band each half of the dipole will be about 259 cm to 269 cm depending on height and desired operating frequency. Please see my video, "Dipole and Inverted V Antenna Basics." Thanks for watching and 73! :)
David Tadlock Big thanks to all from me to all that I can actually view this Best to my knowledge I typed or logged in to RUclips before viiewing and posting here All the best and don't pick upi any of my habits XM 4115216 VE3SQM I am going back to think about drawing out an RF linear mplifier for the cb band and if and take my time ding it If to hard I will go for audio amp Here using a Google login from inn Polsi translating to Engidh and commenting to Americans's !!!!! No interference inteneded. Love your stuff! XM 41 15216 cb callsign and K34 Wsa close to Buffalo New York USA
hiya dave. i'm a general class ham much as i enjoy that, i'm still a cb'r and i talk all the time on it. theres nothing like the thrill of chasing that skip the dx station with home brew antennas makes the victory even sweeter.. 10-160 hf is fun at times just not when it's cq-contest for 3 days strait. i home brew alot of vhf & uhf antennas nothing like talking to a person 15+ miles away on a coat hanger :-)
From camoman...made this antenna this summer works great... Swr was 1.1 on all channels...beats my brothers altron antenna .would a rf choke be useful on this setup..thanks great video.. Also made the peg leg antenna that one is great to..both kick butt
great channel. Dave, can you please make a video for a more practical/popular 11 meter antenna like 5/8 wave or something better you recommend. thanks sir
hi dave, from SANTIAGO DE CHILE, my name is IGNACIO, manufactured your antenna and this excellent roe The manufacture of PVC 3 piece 3 meters each ..... thanks for the tutorial, Greetings
@kd4adv The aluminum does not need to be painted. A 1/2" plastic or rubber cap should be used on the end of the top section. An aluminum antioxidant, available in the electrical section of your local home improvement store, can be applied to the areas where the tubing is fitted together to avoid oxidation between the sections. A wood stiffener should be used in the PVC pipe as mentioned in the video to help with wind resistance. More construction details are posted on my web site. 73 :)
Hi Dave, It's nice to see a fellow ham that does not fold under the pressure of those hams that think they are above everyone else... esp the CB ops that became hams or just plain CBers. You build nice antennas and do a darn fine job teaching us how you do it. Great videos I don't care what the snobs / bullies say. Hams showing CBers how to build things not only helps them learn but also makes some of them realize they want to become a ham also. Thank you for all your hard work, money spent and time invested on the antennas and videos. Mike KD8WBQ 73 P.S I'm from the 11m band and still rag chew there, so I may try this antenna out also. Oh whats your best guess on the gain and max power input on this baby ?
Does it matter if the flat wire is 20 gauge or 14 or 16? Also does it matter if the flat wire is copper clad steel ? Or is all copper better. It is sometimes hard to solder steel. I am going to make one and I dont have the flat wire yet and trying to make a decision. Cost is a factor but I want the low swr so I can get full power. Size dose that matter. Is bigger awg better for transmitting or receive? I want the best advantage too.
hi dave!, ive a openly stupid question. in the hairpin network section. could the soldered conection have a pigtail added. feeding the pigtail to a ground rod, outside of creating an rf loop? well it might not be as stupid of a question as i had hoped. and if your soils water table or ground saturation level is as high as mine. would that not aid to any communication enhancements.
I talked skip from Oklahoma to Michigan and Kentucky every where on my home made J pole copied off of Dave Tadlock it is the bomb. hung it in my tree up about thirty feet for real it worked great!
I would recommend using a decent coaxial choke, these and their relatives are shocking when it comes to common mode current. I also had trouble with a j pole being very sensitive to its surroundings, so you'd tune it close to ground and put it up to height and the SWR would go through the roof. Are they high Q antennas? Anyway, I made a half wave coaxial 4:1 balun and fed it around the 200ohm point and it fixed the problem. That's the beauty of this antenna, you can select an appropriate feed impedance.
Have a swr meter like the one you have hooked up to your radio have a problem the two wires coming off meter have broken off pot ? Red and white wires . Would you happen to know where they attach to? Tks for any info
Built one fucker was huge. Worked like a champ used about 40 feet of fence pipe vertical where the quarter wave section for the J made out of copper. With my little helper it would light a CFL every time I keyed the microphone.
@imbadwrench Probably no. The PVC pipes houses the lower part of the antenna. The lower part of the antenna also radiates part of the signal and transmits the signal through the PVC pipe. The antenna is basically a half wave over a quarter wave length and the signal radiates from the very bottom edge of the twin lead cable all the way up to the top of the antenna. This gives it more gain than a 1/2 wave antenna or a 5/8 wave ground plane antenna.
hi dave, my name is Sebastian and I am from Romania. I want to ask you something: can you give me an example of a cb sky wave antenna? I live in a mountainous area in a mountain valley and I operate with an ground wave antenna and does not work very well. Thank you in advance and I expect your answer (sorry for my bad english)
I like the 'tip over' base of your mast. A pulley where it attaches to the eave might help in raising or lowering the mast. Subbed, also. Thanks for the video, might have to build one for 10m. 73 W7REA
I wish I had more time to devote to radio and inventions. Now I'm obsessed with this low priority mission to launch two mini-video cameras on a rocket, and I don't seem to have much time for that! It might be faster/easier to just buy a rocket. I get more satisfaction doing the research, experimentation, and then building things myself. Now I'm working on a test stand to measure motor thrust! It never ends!
hi dave, wow a fantastic job you did. i see alot of beams from 12 element beams 6 element all kinds that cost hundreds of dollars i would love to have one but the cost is not in my budget. could you do a vid on constructing something like a 6 to an 8 element beam. i run a imax 2000 but recently started to repair and mod my own radios but i have a great interest in building my own beam for 11 meter. i am very impressed with your work i am watching your other vids as well. thank you dave. ben..
Hi, Dave. I can't find the link for the 10 meter version? What kind of coax do I use instead of the twinlead? ..I "liked "you facebook antenna page, too. Thanks, Crazy Bob. WA2CB
Remember that ... when you use A METALLIC MAST, THIS IS ALSO ANTENNA (reins of supports, etc) ... and the coaxial itself if it does not have wave traps😟 (traps are useless, if the coaxial is next to the mast) . If you do not include the MASTS, SUPPORTS, ground, etc, in the designs of antennas by PC, there is no use "the fantastic studies of antennas By PC" 👍
Install a lightening arrestor or static discharge unit in the coax at the base of the antenna. The lightening arrestor has gas filled cartridge that acts like a fuse. A static discharge unit is just a UHF connector with a ground screw on the side of it. The idea is to ground the shield side of the coax. This will prevent capacitive discharge at the other end of the coax. Best protection from lightening is to disconnect the coax before the storm arrives leaving the ground connected. 73! :)
Nice Antenna and great SWR readings. I guess its putting out the full 4 watts. I just bought a old Johnson123A just like that off ebay. I m thinking there wont be anybody to talk to also. LOL. I chose that one because my grandma had one on her old Chevy truck with whips that got out pretty good.
+shartne SWR by itself does not indicate efficiency, A 50 ohm resistor shows good SWR below 1.5:1 over the entire RF spectrum yet it makes a horribly inefficient antenna.. A good way to check antenna efficiency is by checking the Q of the antenna or measuring it's 3 to 1 bandwidth. An antenna that shows a good SWR match over a very large bandwidth is more often than not a very inefficient antenna. For example a 10 meter antenna that covers the whole 10 meter band under 1.5:1 is probably not a very inefficient antenna, The laws of physics state that you can't have both large bandwidth and high efficiency simultaneously. This narrowing of bandwidth becomes more predominant the more you attempt to shorten an antenna. Anyone who tries to sell you an miracle antenna that makes these claims is selling you snake oil. For example vertical omni directional antennas on 20m that cover the entire band with swr below 1.5:1 are usually less than 30 percent efficient likewise antennas that have an SWR bandwidth below 1.5:1 of only 200 khz are usually over 90 percent efficient. Ground mounted vertical antennas with poor ground planes are a perfect example of inefficient antennas that often have very good SWR over a large bandwidth Once again a perfect example of this is the fact that a simple 50 ohm resistor will show an swr of below 1.5:1 over the entire RF spectrum
Hi Dave, Will this antenne handle 200W PEP? I'm from the 79th division and currently using a Procomm PT99 without a GPK. I'm interested in this antenna if you say that it performs better than all those half wave verticals out there. 73's Its more fun in the Philippines!
Hi Dave i have watched all your you tube clips and think their brilliant, i love them hi, favorite is the J pole antenna for CB, i am a licenced Ham G4VVQ, UK amateur, have you thought of doing clip for Doublet antenna, i gave one made from 2 pieces of wire, no joins, spacers are about 3 inches, goes to ATU with 4 to 1 balun, it's 115 ft long, that's as long as i ca get it, works on 40 and 80mts, prob on 160 as well, prob all the hf bands...Fred g4vvq Nr London.
Dave first of all thanks for the video. I'm going to run something by you. I have a 50 ft telescope mast that I run a Imax 2000 on and I've been playing around with a long wire antenna and it actually works decent but what about a horizontal J pole antenna using a mix of PVC and wire for the 1/2 wave length? Wouldn't it be quieter then a vertical? I've always wanted to tinker with a J pole but I haven't as of yet. Is the bandwidth decent on a J pole? Once again, thanks for the video.
Chlorine atoms have a resonant frequency near to 27.275mhz so the pipe might flex more as the pipe softens from heat generated from the vibrations of the Chlorine atoms.
Hi Dave, I have what looks to be smaller gage (cheaper) 300 ohm twin lead that I bought at ACE Hardware. Do you think it would it be ok to use something like this? Or does it have to be a certain gage in order to work properly?
@radiozendermerel It may take some experimenting. Make the wires 103" then tap 6"-12" from the bottom. Move the tap up or down to find the lowest impedance. After that you may need to trim the wires 1/4" at a time to find the best SWR. A ham built one for 10 meters using coax instead of twin lead and there is a link to his project on my web site at amateurradio.bz Hope this helps. 73 :)
Kool how can the twin lead have the ground run beside it w/ out messing it up wow !! The driven element has a reflecter all the way up?? I Stil have a lot to learn thanks KC9YQZ 73.
Make the top part the same as the aluminum tubing, 206". PVC pipe will probably not support the top section. Instead you can use fiberglass tubing, a wood pole or if you have a tree branch high enough you could hang it from a tree using an insulator and an extra amount of wire to attach the insulator. A 1-1/2" wood hand rail 17'+ with the top section taped to it may work best. The same size wood hand rail also makes a very good stiffener to place inside 1-1/2" PVC pipe. 73! :)
@TheZeke1974 After posting my first few ham antenna videos I received many request to do a CB antenna. This was not a problem for me as I like building antennas for all kinds of radios and am always glad to try to help anyone who asks. The CBers all patiently waited and were perfect gentlemen. The one person so far that had a problem with me making this video was a ham and my videos are no longer displayed in his RUclips searches. 73 and good DX! :)
Hi Bob, Visit my website and click on Ham Radio and Other Links. Then click Antennas and it's currently the second link listed. The other antenna builder used RG-213 with a 66% velocity factor. Using RG-213 will make the matching section shorter (1/4 wave free space times 0.66) and should handle more power. Thanks for watching and I look forward to seeing you on Facebook. 73! :)
It should handle 200 watts. The aluminum tubing will handle it but I wouldn't run more than 300 watts through the twin lead cable. The bottom half of the antenna can also be made with coax and would handle more power. I've posted a link on my web site to a 10 meter version, too. 73! :)
I'm trying to figure out how you calculated the length of this Antenna Dave. When I punch in 28.500 MHz into a jpole calculator which is almost in the middle of the 10 meter band, the antenna lengths come very close to the dimensions of yours with a 24.76Ft long side and a 7.8 short side. www.hamuniverse.com/jpole.html
@HamRadio2008 If you build it like this then use lots of tape on the connection between the aluminum tubing and the twin lead. The weight of the coax may cause the wire to break. See my web site for more construction notes. 73 and have fun! :)
Whats up on d'Superbowl? I created one of these with twin lead many years ago. Pulled it up a tree with fishing line. Was an interesting experiment. Imagine the dimensions for a 40 meter version. :) 101 feet long at 7 MHz. I bet it would work very well for DX. Just need a very tall tree! I have trees near me that could host it. Perhaps I will try this someday. I would only have to waste 40 feet of twin lead. :)
1993 The Same year I got my ham license. Unfortunately I got sidetracked from 2 way radio and let my license expire. Now I am preparing to get back into radio and will try to get my old call sign back... ( N8YPS )
Anyone have any ideas for a smaller antenna, and i mean small that can handle 500 watts. I live at an elevation of 2800 ft. with very high cross winds and have lost 2 A99s and an older astroplane to the winds off of a 20 ft. mast. thanks in advance. 11 m DXing.
Robert Neff You can go plenty small. The issue is going to be efficiency. You can get a dummy load that can handle 500 watts; but it wont work very well as an antenna. You can always shorten an antenna by using a loading coil. But it makes the antenna less efficient. Something else to consider is the power level. Why do you want to run such high power? I normally run low power. 5 watts on ham; and 4 watts AM, 12 watts SSB on CB. I have 100 watts at my disposal for HF, but I rarely use it.
purplemutantas to answer the power question , I originally bought the amp to screw with the coal bucket drivers round my parts .Ever hear a jake brake popping off at 4 am,it's not cool. Then one night I started talking to a dude in Honolulu , then next contact was London and another in Panama. I live in Pennsylvania so you could say I was pretty stoked. Got Q cards from a few peeps and now I'm hooked on 11m DXing . I can run from 4 to 500 watts but nothing gets me the range like full power. If I had my way (married) I would love to get my hands on an older Centurion 1000 watt amp and shoot for Beijing or Moscow. Most of the contacts I've made were on 3A Am between 1 - 4 am.
Robert Neff You don't need an amp to talk to people in other countries. From the bay area in California I have made to Japan on 5 watts on 10 meters. Of course I was using a digital mode that is good for weaker signals. But even with phone you can do impressive things when conditions are good. If you want to boost your DX performance work on your antenna. The antenna is much much more important than an amp. If you can't hear the other station it doesn't matter how much power you're running. If you have the means; build a yagi or some other type of beam. I have been thinking of doing a 10 meter beam for a while. If I can make a beam that works on 10 and 11 that would be cool. If space is an issue you could try a moxon beam. That's one I have been eyeing. Even a rotatable dipole can be good. For DX antenna polarity doesn't matter since the polarity of the signal will shift when it bounces off the ionosphere. For local contacts vertical is the way to go as Dave points out in the video.One last thing. If you get a ham license you can run an amplifier legally. You also have access to a bunch of other bands and modes. CB is limited to a few channels and AM or SSB phone only. On ham one of my favourite modes is the digital mode PSK31. It's great for long distance contacts with low power.
***** Thank you for the information . Since my original post I ended up co-phasing a pair of 102" whips from my chimney( windy days they smack into each other), this cpole design though looks like it is definitely what I've been looking for .
I have found the aluminum on ebay for 10 bucks a tube but not sure of the thickness required so that 7/8 slides snugly inside of 1". They have .050 thickness. 1/16" = .0625 which would be too tight so maybe the .050 is good?
I’ve never messed with Aluminium personally. I have used 3/4 and 5/8 copper. I get copper in 20’ sections from a local wholesaler. I won’t say that a j-pole works better but I have noticed a decent drop in general noise.
try 27 foot for the long side 1 foot longer then a 10 meter j pole i built i think it was 9 foot and a 10 foot and a 102 inch fiber glass cb car antenna the short side was arround 9 foot i had 1 inch space between the 2 elemnets
I made all kinds of antenna systems but the 11m J-pole make a double J for 11 lol i made triple J's for 2M I like the J-pole ant. they work great and fun to build oh I have a real nice 6M J pole it's awesome.. DE..N3WYZ 73S
I wish you were my neighbor, lol, I am disabled and not able to make such of an antenna. I live in north Texas, we have lots of activity on CB.I would politely ask if you could help make me one of those antenna's. :)
Наука
A J-pole antenna is different than a ground plane antenna. The longest side of the antenna is approx. 3/4 wavelengths tall and the short side approx. 1/4 wavelength (1 full wave total). The bottom section of this antenna not only radiates part of the signal, it also acts like a matching cable. Tuning impedance to match 50 ohms is done by moving the feed-point up or down between the two sides of the J shape antenna. Mounted at the same height it should outperform any 1/4, 1/2 or 5/8 wave antenna.
Hi Dave. Just wanted you to know that I followed your instructions and built this (my first) antenna. A true success. Used my little 5 watt HT to hit a 144.6 repeater 20miles away, and was heard all over my state. Reports back was "clear as a bell:. Many thanks.
Your stupid this is for cb now ham gay radio
Thank you Dave. I have been experimenting with 450-Ohm ladder versions of the Slim-Jim version. Very impressed.
I tried a few times but fell to make this type of antenna But saw your video and I did step-by-step as shown, and it works. Just saying thanks.
Hi Dave, Jack Wa1ngh, I have built this Antenna 3 times over the last few years and what a great antenna it is. I have found that cutting the long side of the stub seems to work easier for tuning. Thanks for sharing that antenna, it has given me 100 plus countries on 10 meter. Grear Job! 73
Never put antenna cable inside a pole like this guy did on this video I posted reason's in comments
A great video on the cb j pole. Thanks. I still love cb and plan to get back into it after a few years away from it. 73, Bob,VE9EE
My 1st 2 meter antenna was a shop bought "Slim Jim" which is similar in principle to a J-Pole except it has a folded full wave radiator. It had a lot of weather and reliability issues so has been banished into the garage for the past 25 years.
I replaced it with a 3/4 wave ground plane monopole antenna which far out performed it and this antenna has been sat on a mast for 25 years now. This is simply an insulated copper wire PVC taped to a length of white plastic tubing and clamped to the mast with hose clips (We call them "Jubilee Clips" in the UK after the British company that invented them a long time ago).
The same principle could be applied to create a cheap 104 Inch 1/4 wave antenna for CB radio.
Back in my CB radio days in the UK, I ran a shop bought 5/8 wave antenna (4.5 dB gain) but then I built a 3/4 wave antenna (6.14 dB gain) using aluminium tubing. I had to double sleeve the lower 1/2 wave section as the 26 foot rod does whip around a lot when the wind blow, which is probably why the more practical but inferior 5/8 wave is more popular on HF bands.
On VHF and UHF using a 5/8 wave when a 3/4 wave is just as practical just seems silly.
Thank you for the lesson and demo Dave
from Australia
just wonderful video. at first i saw the time of video..length..but after 45 seconds, i knew i was gonna watch the entire show..thank you for your knowledge and willingness to share it.
Horizontally polarized antennas are generally sky wave antennas. The simplest is a dipole antenna mounted horizontally. For the CB band each half of the dipole will be about 259 cm to 269 cm depending on height and desired operating frequency. Please see my video, "Dipole and Inverted V Antenna Basics." Thanks for watching and 73! :)
David Tadlock Big thanks to all from me to all that I can actually view this Best to my knowledge I typed or logged in to RUclips before viiewing and posting here All the best and don't pick upi any of my habits XM 4115216 VE3SQM I am going back to think about drawing out an RF linear mplifier for the cb band and if and take my time ding it If to hard I will go for audio amp Here using a Google login from inn Polsi translating to Engidh and commenting to Americans's !!!!! No interference inteneded. Love your stuff! XM 41 15216 cb callsign and K34 Wsa close to Buffalo New York USA
Great to watch your process! Thanks for the lesson.
wow, very cool antenna. great execution.
I always enjoy your vids.
thank you
hiya dave. i'm a general class ham much as i enjoy that, i'm still a cb'r and i talk all the time on it. theres nothing like the thrill of chasing that skip the dx station with home brew antennas makes the victory even sweeter..
10-160 hf is fun at times just not when it's cq-contest for 3 days strait.
i home brew alot of vhf & uhf antennas nothing like talking to a person 15+ miles away on a coat hanger :-)
Ive hung a coax wire between 2 trees and talked 10 miles away. Kudos for those who want to go to this trouble but too busy for me.
From camoman...made this antenna this summer works great... Swr was 1.1 on all channels...beats my brothers altron antenna .would a rf choke be useful on this setup..thanks great video.. Also made the peg leg antenna that one is great to..both kick butt
great opening theme, great harmonica...cool vid.
great channel. Dave, can you please make a video for a more practical/popular 11 meter antenna like 5/8 wave or something better you recommend. thanks sir
hi dave, from SANTIAGO DE CHILE, my name is IGNACIO, manufactured your antenna and this excellent roe
The manufacture of PVC 3 piece 3 meters each ..... thanks for the tutorial, Greetings
Great video, I enjoyed every minute of it, will make this antenna, mount it on the roof of my two flat, then buy a Ham Radio and see what happens
@kd4adv The aluminum does not need to be painted. A 1/2" plastic or rubber cap should be used on the end of the top section. An aluminum antioxidant, available in the electrical section of your local home improvement store, can be applied to the areas where the tubing is fitted together to avoid oxidation between the sections. A wood stiffener should be used in the PVC pipe as mentioned in the video to help with wind resistance. More construction details are posted on my web site. 73 :)
You are an awesome mentor,thankyou
Hi Dave,
It's nice to see a fellow ham that does not fold under the pressure of those hams that think they are above everyone else... esp the CB ops that became hams or just plain CBers. You build nice antennas and do a darn fine job teaching us how you do it. Great videos I don't care what the snobs / bullies say. Hams showing CBers how to build things not only helps them learn but also makes some of them realize they want to become a ham also. Thank you for all your hard work, money spent and time invested on the antennas and videos. Mike KD8WBQ 73 P.S I'm from the 11m band and still rag chew there, so I may try this antenna out also. Oh whats your best guess on the gain and max power input on this baby ?
Great video. Your antenna looks good.
So Dave, how do you believe this performs compared with a T2LT vertical (same tip height)?
Another great video!
thanks
Does it matter if the flat wire is 20 gauge or 14 or 16? Also does it matter if the flat wire is copper clad steel ? Or is all copper better. It is sometimes hard to solder steel. I am going to make one and I dont have the flat wire yet and trying to make a decision. Cost is a factor but I want the low swr so I can get full power. Size dose that matter. Is bigger awg better for transmitting or receive? I want the best advantage too.
hi dave!, ive a openly stupid question. in the hairpin network section. could the soldered conection have a pigtail added. feeding the pigtail to a ground rod, outside of creating an rf loop? well it might not be as stupid of a question as i had hoped. and if your soils water table or ground saturation level is as high as mine. would that not aid to any communication enhancements.
I talked skip from Oklahoma to Michigan and Kentucky every where on my home made J pole copied off of Dave Tadlock it is the bomb. hung it in my tree up about thirty feet for real it worked great!
I've been licensed since 1996 and they still don't forget!
Nice work. have you tried to use that antenna from 10-12 meter? Maybe with antenna tuner?
73 de LA9OCA
I would recommend using a decent coaxial choke, these and their relatives are shocking when it comes to common mode current. I also had trouble with a j pole being very sensitive to its surroundings, so you'd tune it close to ground and put it up to height and the SWR would go through the roof. Are they high Q antennas? Anyway, I made a half wave coaxial 4:1 balun and fed it around the 200ohm point and it fixed the problem. That's the beauty of this antenna, you can select an appropriate feed impedance.
Nice work, where did ya find the aluminum poles?...
Have a swr meter like the one you have hooked up to your radio have a problem the two wires coming off meter have broken off pot ? Red and white wires . Would you happen to know where they attach to? Tks for any info
How far apart does bottom part of antenna need to be using all aluminum tubing?
How do I get the best signal if im down in a valley using A uniden 510 ? ( im using a 96'' fiberglass mobile antenna 40 feet off the ground) ?
Great info. I am exploring some base station antennas. Notice you said you were in KC. I live in kc too. Also looking for 102" whip.
Built one fucker was huge. Worked like a champ used about 40 feet of fence pipe vertical where the quarter wave section for the J made out of copper. With my little helper it would light a CFL every time I keyed the microphone.
Hi there. Thanks for videos. Find them very helpful and interesting. 73. NZRadioGuy
Thanks for your video!! I’m going to try and collect materials to build this. I might try the wire instead of the tubing inside a pvc pipe.
@imbadwrench Probably no. The PVC pipes houses the lower part of the antenna. The lower part of the antenna also radiates part of the signal and transmits the signal through the PVC pipe. The antenna is basically a half wave over a quarter wave length and the signal radiates from the very bottom edge of the twin lead cable all the way up to the top of the antenna. This gives it more gain than a 1/2 wave antenna or a 5/8 wave ground plane antenna.
hi dave, my name is Sebastian and I am from Romania. I want to ask you something: can you give me an example of a cb sky wave antenna? I live in a mountainous area in a mountain valley and I operate with an ground wave antenna and does not work very well. Thank you in advance and I expect your answer (sorry for my bad english)
Is it true that if you have a long coax you will get bad SWR readings? zerozedzed
That is amazing even X almost equals zero. Way cool... Makes me think of using one on Ten Meters.. :)
73
Jimmy, ARRL TC, WX9Dx
Tell us more about the half square an bobtails, please
I like the 'tip over' base of your mast. A pulley where it attaches to the eave might help in raising or lowering the mast. Subbed, also. Thanks for the video, might have to build one for 10m. 73 W7REA
Can there be other wires inside that section of PVC? like for another small directional antenna? I sorta need a multipurpose antenna.
I wish I had more time to devote to radio and inventions. Now I'm obsessed with this low priority mission to launch two mini-video cameras on a rocket, and I don't seem to have much time for that! It might be faster/easier to just buy a rocket. I get more satisfaction doing the research, experimentation, and then building things myself. Now I'm working on a test stand to measure motor thrust! It never ends!
Dave, where in KC do you live?
hi dave, wow a fantastic job you did. i see alot of beams from 12 element beams 6 element all kinds that cost hundreds of dollars i would love to have one but the cost is not in my budget. could you do a vid on constructing something like a 6 to an 8 element beam. i run a imax 2000 but recently started to repair and mod my own radios but i have a great interest in building my own beam for 11 meter. i am very impressed with your work i am watching your other vids as well. thank you dave. ben..
Hi, Dave. I can't find the link for the 10 meter version? What kind of coax do I use instead of the twinlead? ..I "liked "you facebook antenna page, too. Thanks, Crazy Bob. WA2CB
Remember that ... when you use A METALLIC MAST, THIS IS ALSO ANTENNA (reins of supports, etc)
... and the coaxial itself if it does not have wave traps😟 (traps are useless, if the coaxial
is next to the mast) . If you do not include the MASTS, SUPPORTS, ground, etc, in the designs of antennas by PC,
there is no use "the fantastic studies of antennas By PC" 👍
Would it be possible to make this antenna with twin lead only and install it pvc pipe in one piece? No parts made of aluminum..
AWESOME job ,
Install a lightening arrestor or static discharge unit in the coax at the base of the antenna. The lightening arrestor has gas filled cartridge that acts like a fuse. A static discharge unit is just a UHF connector with a ground screw on the side of it. The idea is to ground the shield side of the coax. This will prevent capacitive discharge at the other end of the coax. Best protection from lightening is to disconnect the coax before the storm arrives leaving the ground connected. 73! :)
Hi Dave, just wondering if you think the antenna is rated for 200 watts or so. Looking to make one for 10 meter. Thanks Joe N2CEP
Can I use 2 pieces of wire instead of the twin lead?
do you have a slim jim j pole version?
Nice Antenna and great SWR readings. I guess its putting out the full 4 watts. I just bought a old Johnson123A just like that off ebay. I m thinking there wont be anybody to talk to also. LOL. I chose that one because my grandma had one on her old Chevy truck with whips that got out pretty good.
+shartne SWR by itself does not indicate efficiency, A 50 ohm resistor shows good SWR below 1.5:1 over the entire RF spectrum yet it makes a horribly inefficient antenna..
A good way to check antenna efficiency is by checking the Q of the antenna or measuring it's 3 to 1 bandwidth. An antenna that shows a good SWR match over a very large bandwidth is more often than not a very inefficient antenna.
For example a 10 meter antenna that covers the whole 10 meter band under 1.5:1 is probably not a very inefficient antenna, The laws of physics state that you can't have both large bandwidth and high efficiency simultaneously. This narrowing of bandwidth becomes more predominant the more you attempt to shorten an antenna. Anyone who tries to sell you an miracle antenna that makes these claims is selling you snake oil.
For example vertical omni directional antennas on 20m that cover the entire band with swr below 1.5:1 are usually less than 30 percent efficient likewise antennas that have an SWR bandwidth below 1.5:1 of only 200 khz are usually over 90 percent efficient. Ground mounted vertical antennas with poor ground planes are a perfect example of inefficient antennas that often have very good SWR over a large bandwidth
Once again a perfect example of this is the fact that a simple 50 ohm resistor will show an swr of below 1.5:1 over the entire RF spectrum
Im using an Antron 99 with a ground plane now and it works very well.
how does this one work, compared to say a coil "end fed" half wave??? "silver rod" type
Love that Harmonica Dave. I've been playing about 50 + yrs. Who is it?
i would like to see a copper j pole for 11 meter and all so how many watts will it handle thanks
can u make a DIPOLE FOR 11 MEATERS OR A YIOGI ANNTENA
Hi Dave, Will this antenne handle 200W PEP? I'm from the 79th division and currently using a Procomm PT99 without a GPK. I'm interested in this antenna if you say that it performs better than all those half wave verticals out there. 73's Its more fun in the Philippines!
That should offer some long term protection. Please post a video response of your antenna if you can. Thanks and 73! :)
Hi Dave i have watched all your you tube clips and think their brilliant, i love them hi, favorite is the J pole antenna for CB, i am a licenced Ham G4VVQ, UK amateur, have you thought of doing clip for Doublet antenna, i gave one made from 2 pieces of wire, no joins, spacers are about 3 inches, goes to ATU with 4 to 1 balun, it's 115 ft long, that's as long as i ca get it, works on 40 and 80mts, prob on 160 as well, prob all the hf bands...Fred g4vvq Nr London.
Dave first of all thanks for the video. I'm going to run something by you. I have a 50 ft telescope mast that I run a Imax 2000 on and I've been playing around with a long wire
antenna and it actually works decent but what about a horizontal J pole antenna using a mix of PVC and wire for the 1/2 wave length? Wouldn't it be quieter then a vertical?
I've always wanted to tinker with a J pole but I haven't as of yet. Is the bandwidth decent on a J pole? Once again, thanks for the video.
After connecting the coax and SWR is good, fil the gap on the coax connection with silliconpaste, so its waterproof and prevents shorts
Chlorine atoms have a resonant frequency near to 27.275mhz so the pipe might flex more as the pipe softens from heat generated from the vibrations of the Chlorine atoms.
That's great Dave, will defiantly be trying to make one of those
Great job Dave, how would you ground the CB J-Pole?
I don't think they need it.
Hi Dave, I have what looks to be smaller gage (cheaper) 300 ohm twin lead that I bought at ACE Hardware. Do you think it would it be ok to use something like this? Or does it have to be a certain gage in order to work properly?
That's a great idea! :)
@radiozendermerel It may take some experimenting. Make the wires 103" then tap 6"-12" from the bottom. Move the tap up or down to find the lowest impedance. After that you may need to trim the wires 1/4" at a time to find the best SWR. A ham built one for 10 meters using coax instead of twin lead and there is a link to his project on my web site at amateurradio.bz
Hope this helps. 73 :)
Hi again how does the ground hook on the twin lead to ground rod that's what I missed thanks.
Kool how can the twin lead have the ground run beside it w/ out messing it up wow !! The driven element has a reflecter all the way up?? I Stil have a lot to learn thanks KC9YQZ 73.
twin lead does not ground
Make the top part the same as the aluminum tubing, 206". PVC pipe will probably not support the top section. Instead you can use fiberglass tubing, a wood pole or if you have a tree branch high enough you could hang it from a tree using an insulator and an extra amount of wire to attach the insulator. A 1-1/2" wood hand rail 17'+ with the top section taped to it may work best. The same size wood hand rail also makes a very good stiffener to place inside 1-1/2" PVC pipe. 73! :)
@TheZeke1974 After posting my first few ham antenna videos I received many request to do a CB antenna. This was not a problem for me as I like building antennas for all kinds of radios and am always glad to try to help anyone who asks. The CBers all patiently waited and were perfect gentlemen. The one person so far that had a problem with me making this video was a ham and my videos are no longer displayed in his RUclips searches. 73 and good DX! :)
Hi Bob, Visit my website and click on Ham Radio and Other Links. Then click Antennas and it's currently the second link listed. The other antenna builder used RG-213 with a 66% velocity factor. Using RG-213 will make the matching section shorter (1/4 wave free space times 0.66) and should handle more power. Thanks for watching and I look forward to seeing you on Facebook. 73! :)
DUAL BAND J-POLE ANTENNA HAM 2 METER 70 CM CNC MADE
HAVE YOU TRIED ONE LIKE THIS, AND IS IT POSSABLE TO DO ONE. DON
It should handle 200 watts. The aluminum tubing will handle it but I wouldn't run more than 300 watts through the twin lead cable. The bottom half of the antenna can also be made with coax and would handle more power. I've posted a link on my web site to a 10 meter version, too. 73! :)
I want to build one!
@zerozedzed Damn, I liked this concept because I hoped the pvc would allow me to get my directional FM antenna further up my mast.
I'm trying to figure out how you calculated the length of this Antenna Dave. When I punch in 28.500 MHz into a jpole calculator which is almost in the middle of the 10 meter band, the antenna lengths come very close to the dimensions of yours with a 24.76Ft long side and a 7.8 short side.
www.hamuniverse.com/jpole.html
Subbed!!!!
very nice
@HamRadio2008 If you build it like this then use lots of tape on the connection between the aluminum tubing and the twin lead. The weight of the coax may cause the wire to break. See my web site for more construction notes. 73 and have fun! :)
Whats up on d'Superbowl? I created one of these with twin lead many years ago. Pulled it up a tree with fishing line. Was an interesting experiment. Imagine the dimensions for a 40 meter version. :) 101 feet long at 7 MHz. I bet it would work very well for DX. Just need a very tall tree! I have trees near me that could host it. Perhaps I will try this someday. I would only have to waste 40 feet of twin lead. :)
1993 The Same year I got my ham license. Unfortunately I got sidetracked from 2 way radio and let my license expire. Now I am preparing to get back into radio and will try to get my old call sign back... ( N8YPS )
@scottsbad383 It will do 4 watts output all day long, friend.
Great!
Anyone have any ideas for a smaller antenna, and i mean small that can handle 500 watts. I live at an elevation of 2800 ft. with very high cross winds and have lost 2 A99s and an older astroplane to the winds off of a 20 ft. mast. thanks in advance. 11 m DXing.
Robert Neff You can go plenty small. The issue is going to be efficiency. You can get a dummy load that can handle 500 watts; but it wont work very well as an antenna. You can always shorten an antenna by using a loading coil. But it makes the antenna less efficient. Something else to consider is the power level. Why do you want to run such high power? I normally run low power. 5 watts on ham; and 4 watts AM, 12 watts SSB on CB. I have 100 watts at my disposal for HF, but I rarely use it.
purplemutantas to answer the power question , I originally bought the amp to screw with the coal bucket drivers round my parts .Ever hear a jake brake popping off at 4 am,it's not cool. Then one night I started talking to a dude in Honolulu , then next contact was London and another in Panama. I live in Pennsylvania so you could say I was pretty stoked. Got Q cards from a few peeps and now I'm hooked on 11m DXing . I can run from 4 to 500 watts but nothing gets me the range like full power. If I had my way (married) I would love to get my hands on an older Centurion 1000 watt amp and shoot for Beijing or Moscow. Most of the contacts I've made were on 3A Am between 1 - 4 am.
Robert Neff You don't need an amp to talk to people in other countries. From the bay area in California I have made to Japan on 5 watts on 10 meters. Of course I was using a digital mode that is good for weaker signals. But even with phone you can do impressive things when conditions are good. If you want to boost your DX performance work on your antenna. The antenna is much much more important than an amp. If you can't hear the other station it doesn't matter how much power you're running. If you have the means; build a yagi or some other type of beam. I have been thinking of doing a 10 meter beam for a while. If I can make a beam that works on 10 and 11 that would be cool. If space is an issue you could try a moxon beam. That's one I have been eyeing. Even a rotatable dipole can be good. For DX antenna polarity doesn't matter since the polarity of the signal will shift when it bounces off the ionosphere. For local contacts vertical is the way to go as Dave points out in the video.One last thing. If you get a ham license you can run an amplifier legally. You also have access to a bunch of other bands and modes. CB is limited to a few channels and AM or SSB phone only. On ham one of my favourite modes is the digital mode PSK31. It's great for long distance contacts with low power.
***** Thank you for the information . Since my original post I ended up co-phasing a pair of 102" whips from my chimney( windy days they smack into each other), this cpole design though looks like it is definitely what I've been looking for .
+Robert Neff what kind of swr do you get hows the performance since you have done this
I like that antenna mount build me one
This is very nice! Wow! Does it work on 11 meter?
Yes it works on 11 meter. The band we use as “cb” here in the US is 11 meter.
@@jcglessner Someone on another jpole youtube says they work as good or better than the SolarconA99. He used 450 ohm ladder lead on his.
I have found the aluminum on ebay for 10 bucks a tube but not sure of the thickness required so that 7/8 slides snugly inside of 1".
They have .050 thickness.
1/16" = .0625 which would be too tight so maybe the .050 is good?
I’ve never messed with Aluminium personally. I have used 3/4 and 5/8 copper. I get copper in 20’ sections from a local wholesaler.
I won’t say that a j-pole works better but I have noticed a decent drop in general noise.
@@jcglessner Thanks! Does 5/8 copper slip inside 3/4 with a snug fit?
try 27 foot for the long side 1 foot longer then a 10 meter j pole i built i think it was 9 foot and a 10 foot and a 102 inch fiber glass cb car antenna the short side was arround 9 foot i had 1 inch space between the 2 elemnets
Nice Microtana power supply!
I made all kinds of antenna systems but the 11m J-pole make a double J for 11 lol i made triple J's for 2M I like the J-pole ant. they work great and fun to build oh I have a real nice 6M J pole it's awesome.. DE..N3WYZ 73S
Horizontal ant is some what quieter. And a good suburban antenna that gets by the hoa.
Still use my cb radio
HI DAVE MAKE ONE FOR 1240 MHZ JPOLE
nice job from hillbilly bob / kb3ufb in pocono mt pa.
I wish you were my neighbor, lol, I am disabled and not able to make such of an antenna. I live in north Texas, we have lots of activity on CB.I would politely ask if you could help make me one of those antenna's. :)
+Scott Castille Hi friend. I live in Joshua Texas. I'm with the American Legion. Send me an e-mail, will see what we can do.
gman76103@yahoo.com