Ham Radio - Quick and easy field antenna
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- Опубліковано 24 сер 2024
- My portable antenna for field day. Quick and easy to put up, great performance, and cheap. What could be better?
Here is a link to the commercial UnUn that I used in the video.
www.balundesign...
Also check out my 40-15 meter remote tuned magnetic loop:
• Ham Radio - Magnetic l...
And my 160-80 meter 6ft. magnetic loop.
• Ham Radio - 80 160 met...
This is exactly what I was looking for. I'm getting into CW QRP as a new ham, I live in a house with a tiny garden where I'd struggle to fit quarter-wave radials, and I wanted to get on the 17m band. This is perfect, thank you very much for sharing your insights.
Kevin you're a good man! Thanks for all your vids from an unlicensed viewer friend.
Awesome! Not only a great antenna but a great presentation as well. So tired of UA-cam videos where the presenter is hand holding it. Kevin you do it right. Stable video + good audio = a pleasant video to watch multiple times. You have a new subscriber. Thank you so much!
The icom ic-745... my first rig 😊
Loved it and today I am looking for one.
Great video Kevin, just made a 9-1 myself so will look into doing this myself, love portable operating and doing things on the cheap!
Thank you for sharing a local ham and I speaking of this type of antenna a few days ago. Great to see it explained and put up. Thank you again.
KJ6IHZ
73
You're welcome Myles. Give it a try, you'll love the performance.
If not He will Suck.Your.Ham
Thanks for this video. I built one, strapped it to the post of a 6’ privacy fence that is around my Hottub and wa-la..I have worked stations from Florida to Arizona to Wa, Ontario on ft8.30,20,17,15 and it is usable on 10 meters as well. Was using my 891@ 30 Watts. Nice application.thanks.
KEVIN, I did add 3 radials.
This gives me great hope. I recently bought an SDRplay RSP1A receiver which I have attached to an indoor slinky antenna. Not real happy with the results but out in the garage I have all the parts to build what you have made. When the weather dries out I’ll give it a shot. Thanks de N0WDM
Sir kevin its good to know that kind of antenna..wish more info of those for my 1st rig as a foundation class ham operator..
I love this, thanks! It's exactly what I'm looking for to do some SOTA work. I will definitely give this a try.
You won't be disappointed. Make the radiator 16' and it will be just a bit better on 20 and still good up on 15 without a tuner. Does ok on 30 when using a tuner, but you need a longer radiator for 40 for it to be efficient.
Just made my own version of this using 17 feet of wire and a 9:1 unun with 33feet of coax feed line. SWR as follows: 40m 1.8 across the band, 20m 1.3 across the band; 17m 1.3 across the band; 15m 2.2 up to 2.5; 12m 3.5 across the band; 10m 5.0 across the band; 6m 4.5 up to 4.9. So with an external tuner with my 857d I think I should be able to work a lot of bands! Many thanks for the guidance Kevin 73s.
CT 2116 Tim what wire did you use in your setup?
Simple single strand electrical wire
God improvisation! I love those"bulldog jaw" clips. I use them to jumper my mobile whip to my endfed antennas for semi portable operation in my yard, as you can see on my YT videos and QRZ.
Great video and presentation. I'm a EFHW junkie and this config is nice. Well done.
Excellent presentation, thank you. I've been tinkering around with verticals, masts and guys and just figured I'd experiment with a plain wire in the sky, as high up as I could get it, so I'm working on a small helium balloon lifter and two to three thin guys to keep it stable during wind. I mean, if you free the wire from the mast, you can go really high, and we all know what that means for takeoff angle. I haven't seen much on balloon lifts for antennas, so I'm having to improvise a lot. KG7OIY
I heard a guy who uses a balloon to lift a long wire antenna every night! He is able to operate on 80 meters, and beat his HOA!!! ;)
Great video and antenna Kevin, thanks for sharing it and keep 'em coming! 73, de KO8S
Great video and nice work!
Very fascinating and detailed! Wish I knew more about it! I've seen some field day videos and they seem like fun events!
+539 Productions Thanks. It is fun. Field day started as an emergency preparedness practice activity, way back in the late 40's or so. Now it's an annual contest. Operating radio in the field is kind of fun anyway. Being able to talk to the world from anywhere.
Kevin Loughin Even a few off-world! I've heard at the right time you can contact the ISS!
539 Productions Yes, you can. If you want to listen, use any ISS tracker, many on the web, and figure out when it will pass over you next. During the pass, tune any VHF capable radio to 145.8 Mhz, FM.
Kevin Loughin Awesome! Thanks for all the info!
I'm running a 9:1 unun end fed from my rooftop to a tree in the back yard. It tunes up from 80 up to 10 meters low SWR on all ham bands. The long wire is somewhere between 50-60 feet. I've got a couple QRP versions built but untested at about 36 feet. I may chop one down some and send it up on my painters pole.
Should make a decent DX antenna with the lower angle of radiation due to it being a vertical. You've probably seen this SWR vs length chart for the 9:1 unun.
2.bp.blogspot.com/-zilWk4agBjI/V6OoepSNrKI/AAAAAAAADDY/gUVf8E6OsZ07mPzdO83lIBZsyMCdRTZgACLcB/s640/UNUNwires.JPG
I actually haven't come across that. Thanks for the link.
I got a chuckle on your QRZ page... Sitting in that Mustang holding on to a non-existing steering wheel??
Kevin Loughin its there lol. It's just blocked by the front A-Pillar so you can't see the wheel itself. I really need to update that page. A storm took out one of my two trees killing my dipole, this the end fed.
Hi Kevin - one thing I need to check with you. Is the pole you use fiberglass? If not is it steel/aluminum and if so I suppose it doesn't de-tune the antenna?
It's fiberglass and non-conductive. You couldn't use a steel mast, it would detune the antenna. Unless you isolate the bottom of the mast and just use it as the antenna.
Great video Kevin, I learn so much from you videos man.... trying to build a Mag loop now, thanks again KD9GRP
Thanks for the video and I'll be passing it on.
73s
+Dennis Petersen Thanks Dennis. Positive feedback encourages me to do more. And thanks for sharing it, that helps me. 73
Hi Kevin, I been looking for a project to use my 9:1 unun that I build , I can
now put it to some use. Roger
Hey Roger, great! Let me know what you think of it after you play around with it a bit. BTW, If you add about a foot to the wire, it will favor 20, but still be fine on 15.
Would this work well if I were to put a wire up about 40 feet vertical into a pine tree for 20, 30 & 40 meters?
Yes! Shoot for 42ft or thereabouts. It would probably also work on 80, but not quite as well as a half wave dipole. If there's room along the ground, bury a radial or two, about as long as the radiator and it will also improve it.
Hi Kevin, Feedback on the antenna project. I now build it and is working great, work US on it on 20m on QRP 5 watts in the afternoon (my time GMT).
I live in Cornwall -UK. Use 16' of wire with 35' of coax cable on a 26'/ 8m flagpole. The SWR is 1.2 on 20m. It will tune OK on 40m/80m with a ATU ,but as you pointed out it a little short for 80m ..Roger MK6RIU
Hi Roger, thanks for the feedback! I've worked across the pond QRP on it several times. 73.
What radio were you using with your antenna? Wondering if I could use my Anytone D878 UV with that set up for remote contact Bob in WV. KE8QMW.
This is a brilliant video, well done! Can you tell me the type of wire you used as the 15 foot radiating element plus the wire you used for the 27 feet needed to work 40m? Great job. 73s Tim
Hello Tim, Any wire will work. I had some multi-wire cable laying around so I just tied all the conductors together and used it as the radiator. The extension was some solid wire I had on a spool. I think it was for wiring up doorbells.
I use some leftover Ethernet cable, works great.
Great video!! Check out the TRX communications 392m
Thanks for the great video. Question. How do you configure the 27 foot section of wire for 40 meters after connecting it to the 15 foot section?
I use a rock to toss a line up over a tree branch and pull the wire end up.
If I understand correctly than the 15 foot of wire goes vertically up the pole and the 27 foot section goes at an angle out to the tree.
+Wallace Sheaffer or almost vertically, if you find a tall enough tree.
OK, Thanks I think I got it! Great project. It is sure less expensive than a Chameleon CHA Mini. Of course that is not exactly apples to apples.
I'm thinking about this for the Jamboree On The Air (JOTA) on 16 October 21. Would you be able to share how this design could be modified for 100W use? I can turn the power down to QRP, but what would need to be done to use more power?
Just wind the 9:1 on a larger core and use heavier wire.
You'll probably also want to run a counterpoise wire off the ground side at the base of the antenna and install a common mode choke to keep the RF off the feed line shield.
Kevin: Where did you source the fiberglass pole support and pole?
KC1NRJ
Greg
That was one of those telescoping sign poles like you see in the yard in front of fast food joints and small shops. You can find them by searching for telescoping sign pole.
Good nigth , that the only probem that I can see was that noseen the pregesive talation step by step wuld be fine like this way. Thankyou. Brother
There a old big tv antenna on roof with rotating remote, would this work for beginner listen only then licensed talk ham radio?
Yes, but not very well. That antenna is going to be resonant on the analogue TV bands in the VHF and UHF range. Also, it's going to be horizontal and directional at those frequencies.
It might work well enough on the 2 meter ham band, but most activity there is done with vertically polarized antennas and signals would be reduced by the horizontal TV antenna.
Do you have the info on the "advertising pole" used?
I have bullet 55. 55ft ant and 9:1 .. will add wire lower swr. ...
Great presentation! Could tell me more about the optional antenna tuner you showed briefly and was contained in your antenna go bag? I am a new General class ham and plan to build this antenna for portable operations. I would also like to become familiar with portable antenna tuners and maybe even build one at some point. Thank you.
The tuner was a kit. It's a Z-match tuner. It has a pretty broad range of impedance matching, but may not be as efficient at transferring power to the load as a simpler L-network tuner. I might do a video on that tuner this weekend.
Ok. I look forward to that video. Thank you for your response.
Nice video. What I have is a "cut for 10 meters" antenna. I was thinking of using this way of putting up my antenna as a vertical. I know...10 is dead, but it's all I have for now. supposedly on this mono-band antenna, I don't need a tuner. The manufacturer says it is tuned for 28.3 to 28.5. Any further use of the band of course would require a tuner. Any suggestions?
I guess I'm just not clear on what you're asking. You can mount a 10 meter antenna vertical if you want, it should work that way.
You might be able to load it up with a tuner on the lower bands, but it's not going to be very efficient and not going to work well.
Hi Kevin
Have you checked if your feedline is radiating? You would proably have CM on the outside of the shield. No HF in the shield of your rig? Nice video though.
+SM7FBJ I did walk the line with a field strength meter and didn't see much until I got closer to the antenna. I'm sure there is some radiation, but not too much. I probably wouldn't want to run a lot of power on this configuration though. My use is a field antenna, and I usually am QRP to around 30 watts max in that scenario. Thanks for bringing that up, I probably should have mentioned it.
+Kevin Loughin
Ok working QRP. So do I when /P with my K2. My "portable" antenna this summer will be a delta loop, 2 fishing rods 20 feet each making a "V" and fed with open wire with my QRP Z-match. It will be rotateable and maybe I'll get a T1 ATU from elecraft.
When changing frequency / band doesn't the VSWR meter need to be re-calibrated to show accurate reflection?
Not if you're using a cross needle meter. It has two movements and needles. One shows forward power, the other shows reflected. The point where the needle cross each other shows SWR.
Hi Kevin. Thanks for an informative video. I'm just starting out and have been gifted a second hand Kenwood TS 570DG - but no antenna, so I'm doing some research and came across your vid.
I have a theory question if you're up for it? I understand the coax impedance and I understand the unun turns ratio to get the impedance transfer of 1:9 taking the 50 ohm coax to the 450 ohm wire. But..... where / how does the antenna wire get a 450 ohm impedance - it's just a wire, so what's the physics that makes your particular wire exhibit a 450 ohm impedance. (Apologies for the 101 question.)
Thanks again for making the video.
A resonant wire antenna will exhibit a higher impedance the further you go from the center of the wire. At it's resonant frequency, the impedance at the end of the wire will be quite high, maybe even over 1K. The unun brings that down to something lower. I find it works best if you use a tuner. the unun brings the impedance down to a range where the tuner can handle matching it to the 50 ohms at the TX.
@@loughkb Hey Kevin. Many thanks for replying. I really appreciate the help.
Hi Kevin can you possibly explain to me how the outer coax acts as a counterpoise ( how it connects to the unun ) Thanks Darren
If you look at the drawing of the UNUN, you'll notice one side of the transformer is connected to the outer shell of the SO239 connector. Electrically, the coax shield becomes the other half of a dipole. This is fine for QRP. However, if you're going to run power on an antenna like this, you would want to run an actual counterpoise wire away from the coax to draw off the current.
You should make and sell these!
Interesting! What length of vertical wire would you recommend using with the 9/1 unun, if I just wanted to work 10 or 12 meters without a tuner? ;)
Experiment! Start around 14 feet and trim back until you find a happy range.
Took your advice, and found that a 9:1 unun works well on 10 through 12 meters with around a 10 to 11ish foot long antenna! Used a tape measure for the antenna element in my experiments!! ;)
How did you determine to use a 9:1 unfunny?
Great vid Kevin. I am building a 9:1 right now. Gives me hope that my project will work. Where did you get those oval insulators? sub'd
Those are individual links from a decorative plastic garden chain. I bought 20 feet of chain for just a few dollars, and I've cut out individual links to use as insulators over the years. They hold up well outside.
Greetings. Kevin, Where do you get the sharp piece that you buried in the ground?
It came with the telescoping sign pole. It's simply a sharpened fiberglass rod. You could purchase a wooden dowel, or plastic rod and sharpen the end. Even a straight stick would probably work.
Thank you for answering so quickly. 73 de KP4JS.
Heya Kevin. Do you have a manufacturer and part number for that fiberglass stake to hold the pole? I like that it has a washer to stop it when you get to a certain depth. Very cool how the telescoping pole slides right on top.
Hello Steve. The stake came with the telescoping pole. I would assume that when you buy one of those poles, you probably get the stake along with it. If not, you might have to get creative. ;-)
Ahh, gotcha. I'll probably look into tree stakes and saw them up or something. Thanks for the great video! Nice work.
Small diameter PVC pipe might work, you could sharpen the end. You might also be able to get plastic rod from the hardware store and just cut a section.
If you build the antenna, you'll be surprised at how well it performs. I've used it a bunch.
Oh wow!! Look at your hair!!
wow you didnt spend 500 plus bucks on a store bought antenna 9 to 0ne ballun is the way to go kg6mn
Just to clarify Jerome, it's an UnUn. Unbalanced to Unbalanced.
great video thanks for sharing WA0AFB
Here is one more option, K3MT Grasswire Antenna: ua-cam.com/video/aSioSzSiScc/v-deo.html
It would have been more interesting if he'd gone down on the deck and setup with none of the wire hanging up in the air. He's got about 20 feet of it up off the ground, hanging down from that second story window. More than enough to be a very effective radiator on 20 meters, and somewhat effective on 40.
A wire on the ground is going to be an NVIS antenna, radiating most of it's signal almost straight up with the earth as a reflector.
QRP FOR LIFE xd
great idea have copied an works really well simple is best G0NVF 73
Thanks Dave, it's good to know. I often wonder if anyone else makes use of my ideas. I've used this little antenna a bunch.
2019
unun yes suree bob
73
you can vacuum around you?!!!
I'm sorry, I don't understand what you're referring to. Could you elaborate please?
Kevin Loughin at the beginning of your video is much dust on your radio if you wipe it be good for you
thanks
Ha! It's the maids year off. I guess I should clean up around here. ;-)
I went back and looked. I think you're seeing a little sawdust inside the plastic lens. I rescued that old Icom from my dads basement where it was completely covered in sawdust. I just haven't taken the lens off and cleaned in there yet.
Ham freak