Dave, I have been a ham since some time in 1971. Those days you built what you needed! Recently retired, my ham radio hobby is once again an interest. Its a breath of fresh air to see someone "build" something! You don't always have to buy it. Build it! Thanks for ALL your videos! Soon this balun and other projects of yours will be in use here! Thanks! 73's Don Wb9hzx
Hi Dave, Really enjoy your videos and your running commentary. Got me back into Ham radio and am gathering bits to construct my own baluns. Thanks. VE3WNS and M0CEL
Great video Dave. If I might make a couple of suggestions. Instead of drilling out the SO-239 to a clearance hole, drill and tap it to eliminate the nuts. Another idea is to put the side eye bolts in the body of the tube spaced down a little to clear the cap. That way you don't have to notch out the tube (body) of the balun and connecting the leads is so much easier. It ends up a little longer but much easier to build. At least that is how I have been building mine. 73 N8REZ
I like using fine grit sandpaper for cleaning off enamel-coated wire. Can an organic solvent also be used to do this? Obviously, this is to be done neatly without slopping it all over other wires. Acetone ? Ethyl Acetate ?
Hi David. I am a bit confused. If its 1 to 1 Balun its 50 ohms in and out is 50 ohms. So how does it match centre fed aerial impedance. l am also assuming its un balanced to balanced Balun you have made. I am still learning shouldnt it be a 4 to 1 balun. Before I start making one of these can you confirm. I am just getting back into radio. Cheers from old George. 🤠🇬🇧👍
I wonder if it would be better balanced to have the two wires that run at right angles to the coil not so close to each other but one on one side and one coming up the other side of the coil? But maybe this is how you have seen or read about it and that's why you do it the way you did. To the people that are worried that it is a dead short, just remember it is a coil. A quad antenna or a loop antenna or folded dipole has the inside of the coax connected to one end of the element or wire and the brade of the coax to the other end or the element or wire. You could think how can that work as you are shorting out the inside and outside of the coax, but it works. In DC it would be a short but it is AC so it's not a dead short.
Hi Dave - Nice work! I especially like how neat your work area is. Unfortunately I can't say the same about my own. Please explain the reason why, when you took the ends of the wires and crossed back over the top of the wires making up the coil (the wires wrapped around the coil form), you left a small gap bridging the wrpped wires. This can be seen at the 2:19 mark in your video. Is it because thge enamel coaing is not sufficient to insulate?? Thank you in advance...I just want to make darn sure I do it correctly when I make one of these. 73's
If I wanted SO-239 on both ends, I would use the same connections as on the first end you made. Same center conductor as the one side and shield the same. So would end up with the center conductor reading short and the shield shorted or some amount of resistance I assume? Thanks! Bill
Hi Dave, because you folded the center end over and soldered to the others isnt it all one long wire now ie the balan is shorting out the + and - of the feed? Cheers Tim
Great videos! I run a fan dipole for 160, 80 (75), and 40 meters, and pick-up a lot of electrical / atmospheric noise, and do occasionally get some RF on my shield, will this balun cover all three bands (and maybe a 4th band)? I am going to rebuild my dipole very soon and build this balun. I'm still quite new to the hobby (2012) and am always looking for a better way to build my own antenna. Thanks again for the great videos. 73 de AD4GC
Probably not a good idea. It would no longer be an air core inductor. Also leave a gap between the middle wire leads and the coil, as the leads run across the coil. If the gap is slightly too wide you can push the wire down as it is inserted into the PVC pipe body.
I wish he would answer this question. I'm also confused how it works. I built one and I'm actually afraid to use it until this is explained. I would really like to get on 20 meters and I'm stuck waiting on confirmation. PLEASE ANSWER THIS DAVE!
+Micah Haislett Test it before using it. Here's how: th-cam.com/video/nvlQ25hTTXg/w-d-xo.html Be sure to use 14 gauge enamel coated magnet wire to make it with. Regular electrical wire will not work. 73, Dave
ola, tenho uma g5rv, com acoplador militar manual, fiz um balum com coaxial após a descida de 400 ohms, qual balum fazer para ela? 1:1 , 2:1 ,obrigado!
I tried it using all the precise measurements, but it seems like 9 turns wasn't enough to make the wires fit snuggly between the drilled holes. I think I would have drilled them at least 1/16 inch closer (end to end). So instead of 1 and a hair over 15/16 of an inch, I think 1-7/8 inch might have worked better. Also... my last hole was much closer to the end of the pipe than 1/4 inch. This made everything look off center. I think drilling the holes 1-7/8 inches apart would have made it both fit better and appear more centered on the pipe. Just my opinion.
I think someone needs to start using a liquid flux to clean their solder connections to make soldering a little easier. This would be another good chance to use some heat shrink on yet another connection and even some more flux
Dave - interesting to follow and build my own - a couple of thoughts (that I just trusted as I went along believing the internet guides.) Firstly outside of Continental USA discovering what thickness or international (ie rest of world) 14 Guage wire is - google has solutions from 0.63mm - 0.81mm I suspect that it is over 1mm given the video for reference. Secondly your video build results in a dead short, (as I suspected) since both the centre and shield from the SO239 are connected to the centre enamel coated wire making up the Balun. Please rectify this
You'll probably need to find a wire size chart to compare the 14 gauge AWG wire. I bought some from Amazon. Yes, it is a dead electrical short but this is RF and not electricity. See the video Testing a 1:1 Air Core Current Balun. Thanks & 73.
Dave, I love the video! I’m pretty new to the hobby and I wanted to build a balun, but when I built the balun I discovered a continuity problem. It seems that the balun is shorting our, or is that what is supposed to happen. Any advice? Thanks KC9ZHU
did you ever figure this out Bob? It really does not make sense to me to have continuity across all leads. Please let me know before I hook this thing up to my equipment haha
Hi Dave, I posted on Facebook on the Ham Radio Homebrew group a picture of my 1:1 air core balun that is modeled right after yours. my coil isn't exactly neat meaning I goit some gaps that I couldn't quite get straightened out. Do I need to start over or am I in the clear? you can respond to me on Facebook or through here.
You probably can't help but to get one or two small gaps in the coil. Place a 50 ohm resistor across the leads at one end and check it with an SWR meter or analyzer. I'll look for your picture on Facebook. 73
ZERO reason to put a balun on a dipole. Baluns are not for antennas, they are transmission line couplings ( Lines, Waves and Antennas, PHd Authors .None of mine have baluns and I work 5,000 mile CW contacts with ONE WATT regularly. .They are 1:1 match and two of them are 1:1 match across the entire band. .This video is just repeating 80 year old fables.
Dave, I have been a ham since some time in 1971. Those days you built what you needed! Recently retired, my ham radio hobby is once again an interest. Its a breath of fresh air to see someone "build" something! You don't always have to buy it. Build it! Thanks for ALL your videos! Soon this balun and other projects of yours will be in use here! Thanks! 73's Don Wb9hzx
I'm hope you're still doing it. I'm a younger man and I love building the things I need!
Hi Dave,
Really enjoy your videos and your running commentary. Got me back into Ham radio and am gathering bits to construct my own baluns. Thanks. VE3WNS and M0CEL
I have built a couple of these and they work very well.
Great video Dave. If I might make a couple of suggestions. Instead of drilling out the SO-239 to a clearance hole, drill and tap it to eliminate the nuts. Another idea is to put the side eye bolts in the body of the tube spaced down a little to clear the cap. That way you don't have to notch out the tube (body) of the balun and connecting the leads is so much easier. It ends up a little longer but much easier to build. At least that is how I have been building mine. 73 N8REZ
This looks like really nice coils . But I am not flowing in my head what this looks like. Do you have a drawing of this?
A schematic would be super helpful in determining those connections
Any chance or uploading one?
What size PVC pipe is used and how many mm of enamel wire and how many turns...?
MNY TNX
I like using fine grit sandpaper for cleaning off enamel-coated wire. Can an organic solvent also be used to do this? Obviously, this is to be done neatly without slopping it all over other wires. Acetone ? Ethyl Acetate ?
Hi David. I am a bit confused. If its 1 to 1 Balun its 50 ohms in and out is 50 ohms. So how does it match centre fed aerial impedance. l am also assuming its un balanced to balanced Balun you have made. I am still learning shouldnt it be a 4 to 1 balun. Before I start making one of these can you confirm. I am just getting back into radio. Cheers from old George. 🤠🇬🇧👍
hello, how to check which radiator in the case of a dipole? since it is unun electrically shorted ?
Hello, have you ever done a video on making a mini-whip antenna? If not, what is your opinion of them?
What is the thickness of winding wire or swg?
Put the flange on the inside of the cap and put a washer and nut on the SO-239 on the outside of the cap. Four less holes that could leak water.
I wonder if it would be better balanced to have the two wires that run at right angles to the coil not so close to each other but one on one side and one coming up the other side of the coil? But maybe this is how you have seen or read about it and that's why you do it the way you did. To the people that are worried that it is a dead short, just remember it is a coil. A quad antenna or a loop antenna or folded dipole has the inside of the coax connected to one end of the element or wire and the brade of the coax to the other end or the element or wire. You could think how can that work as you are shorting out the inside and outside of the coax, but it works. In DC it would be a short but it is AC so it's not a dead short.
Hi Dave - Nice work! I especially like how neat your work area is. Unfortunately I can't say the same about my own.
Please explain the reason why, when you took the ends of the wires and crossed back over the top of the wires making up the coil (the wires wrapped around the coil form), you left a small gap bridging the wrpped wires. This can be seen at the 2:19 mark in your video. Is it because thge enamel coaing is not sufficient to insulate??
Thank you in advance...I just want to make darn sure I do it correctly when I make one of these.
73's
Thanks for sharing this excellent video and you thoughts..
73 Steve AA4SH
If I wanted SO-239 on both ends, I would use the same connections as on the first end you made. Same center conductor as the one side and shield the same. So would end up with the center conductor reading short and the shield shorted or some amount of resistance I assume? Thanks! Bill
awesome dave good job
The videos are very good, but I can't find the measurements. I would greatly appreciate if you could provide them to me. Thank you!.
Hi Dave, because you folded the center end over and soldered to the others isnt it all one long wire now ie the balan is shorting out the + and - of the feed? Cheers
Tim
How many turns did you use for each coil ? Was it twenty turns or something more or less ?
it will be the same in the comet cbl 2500 shorted on the ferrite core
Great videos! I run a fan dipole for 160, 80 (75), and 40 meters, and pick-up a lot of electrical / atmospheric noise, and do occasionally get some RF on my shield, will this balun cover all three bands (and maybe a 4th band)? I am going to rebuild my dipole very soon and build this balun. I'm still quite new to the hobby (2012) and am always looking for a better way to build my own antenna. Thanks again for the great videos. 73 de AD4GC
Hey Dave! Thanks for the many nice videos. However, I was wondering if it is possible to lay cables inside the coil, instead of outside?
Probably not a good idea. It would no longer be an air core inductor. Also leave a gap between the middle wire leads and the coil, as the leads run across the coil. If the gap is slightly too wide you can push the wire down as it is inserted into the PVC pipe body.
Thanks Dave, very nice work. Although, I don't understand how it works when there is continuity throughout.
I wish he would answer this question. I'm also confused how it works. I built one and I'm actually afraid to use it until this is explained. I would really like to get on 20 meters and I'm stuck waiting on confirmation. PLEASE ANSWER THIS DAVE!
+Micah Haislett Test it before using it. Here's how: th-cam.com/video/nvlQ25hTTXg/w-d-xo.html
Be sure to use 14 gauge enamel coated magnet wire to make it with. Regular electrical wire will not work.
73, Dave
These measurements can provide information about balun Do?
superbowl training video? LOL Another great one Dave!
ola, tenho uma g5rv, com acoplador militar manual, fiz um balum com coaxial após a descida de 400 ohms, qual balum fazer para ela? 1:1 , 2:1 ,obrigado!
I tried it using all the precise measurements, but it seems like 9 turns wasn't enough to make the wires fit snuggly between the drilled holes. I think I would have drilled them at least 1/16 inch closer (end to end). So instead of 1 and a hair over 15/16 of an inch, I think 1-7/8 inch might have worked better. Also... my last hole was much closer to the end of the pipe than 1/4 inch. This made everything look off center. I think drilling the holes 1-7/8 inches apart would have made it both fit better and appear more centered on the pipe. Just my opinion.
I think someone needs to start using a liquid flux to clean their solder connections to make soldering a little easier. This would be another good chance to use some heat shrink on yet another connection and even some more flux
qual seria o tamanho da delta lupe para o balun de 4.1?
Dave - interesting to follow and build my own - a couple of thoughts (that I just trusted as I went along believing the internet guides.)
Firstly outside of Continental USA discovering what thickness or international (ie rest of world) 14 Guage wire is - google has solutions from 0.63mm - 0.81mm I suspect that it is over 1mm given the video for reference.
Secondly your video build results in a dead short, (as I suspected) since both the centre and shield from the SO239 are connected to the centre enamel coated wire making up the Balun.
Please rectify this
You'll probably need to find a wire size chart to compare the 14 gauge AWG wire. I bought some from Amazon. Yes, it is a dead electrical short but this is RF and not electricity. See the video Testing a 1:1 Air Core Current Balun. Thanks & 73.
i am a newbe and when i used a multimeter on all leads the all had continuity is that ok.
this doesn't make sense to me either. Did you ever figure it out?
Dave,
I love the video! I’m pretty new to the hobby and I wanted to build a balun, but when I built the balun I discovered a continuity problem. It seems that the balun is shorting our, or is that what is supposed to happen. Any advice? Thanks KC9ZHU
did you ever figure this out Bob? It really does not make sense to me to have continuity across all leads. Please let me know before I hook this thing up to my equipment haha
Hi Dave,
I posted on Facebook on the Ham Radio Homebrew group a picture of my 1:1 air core balun that is modeled right after yours. my coil isn't exactly neat meaning I goit some gaps that I couldn't quite get straightened out. Do I need to start over or am I in the clear? you can respond to me on Facebook or through here.
You probably can't help but to get one or two small gaps in the coil. Place a 50 ohm resistor across the leads at one end and check it with an SWR meter or analyzer. I'll look for your picture on Facebook. 73
esse esta pelo menos completo o anterior nao tem dimensoes do tubo e tambem o tipo do cabo
Dave! Thank's for your videos! I just wished that you were my neighbor. KN4UXO
Look's like my 9:1 Balun
good
Thanks!
AMIGO ODRIGADO PW8BR 73
Solder gun is much better!
Go to Facebook type in 440 CB shop and read the reviews
Balun hf Istanto robot
ZERO reason to put a balun on a dipole.
Baluns are not for antennas, they are transmission line couplings ( Lines, Waves and Antennas, PHd Authors
.None of mine have baluns and I work 5,000 mile CW contacts with ONE WATT regularly.
.They are 1:1 match and two of them are 1:1 match across the entire band.
.This video is just repeating 80 year old fables.