Nelson Antennas End Fed "Random Wire" HF Dipole 9:1 Antenna
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- Опубліковано 6 лют 2022
- A full review of the Nelson Antennas END FED "RANDOM WIRE" HF DIPOLE 9:1 ANTENNA.
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#hamradio #pota #parksontheair - Наука та технологія
9:1?
So 50 ohm in, 50/ 9 = 6 ohms out?
It wont work with a shorted feedpoint.
Whoever made this video knows NOTHING ABOUT RADIO.
This is literally one of the dumbest comments I have ever had on the channel. You should maybe think about turning in your ham radio license until you learn a little more about antennas, and a little less about being a keyboard commando. I'll wait for your apology when you realize how stupid you are.
@@hamradiotube this made me laugh for 1 week, just wonder how long it takes him to realize
SO every antenna you put up is perfectly matched?
A 9 to 1 unun is 450 ohms converted to 50 ohms they can actually work on odd and even Harmonics when you get the length right usually fairly long.
A half wave works on odd Harmonics and has very high voltages at the balun but also work well
But needs a 49 to1 or a 64 to 1. A 16 to 1 can work better than a 9 to 1 and will need a shorter wire.
Chuck AA4CP
@@hamradiotube His ignorance shouldn't really be an excuse for your, mildly said, inappropriate response. Ignoring it would have been much better.
My Nelson matchbox has been in constant service and out in the weather since 2016. It's been through hurricanes and killing sunshine and rain, etc. And, it's survived it all. The last hurricane, Ida damaged it and I had to glue the case, etc. But, it's back in service and gets every band I need. Great little matchbox!!
5:22 Love the part where your neighbor comes out and thinks "What the hell is Mike doing now???" LOL
nah, they're used to it.
That was no neighbor. He was an alien that teleported away once he knew the cosmos was not in danger.
@@Aimsport-video Maybe it was an alien doing POTA - Planets on the Air
Thanks Mike from Sth East VK . I have 2 of these, one paired with a 71 foot wire and 16 foot counterpoise. Anything from 40 metres to 10 works really well. Australia is a long way from Europe and Nth America, but I've already managed good contacts with both continents using about 90 watts. Nelson Antennas are onto a winner with this little product.
Nice video Mike,
Another fun video, I was impressed with your MFJ tuner that was cool. I have an LDG here at the shack that I really enjoy, so I look forward to seeing what it will do.
That was also very nice of Nelson Antennas to give you that promo code.
Again nice work, thank you for the shout out but I'm happy to help the channel. 73 🤘😎👍
Thanks Jose. The MFJ tuner is amazing. I love it. LDG's are prob even better. Unfortunately I took the antenna down and will be sending it back to you tomorrow. Thanks again and 73!
Your a bad man for your videos. I have followed you for a year. I have bought or built many antennas. Keep up the outstanding job Mike.
Talk about perfect timing ive been wanting to buy this for portable ops!
I own two of Nelson Antenna's 9:1 UNUNs, one with a UHF female connector and the second with a BNC female connector. The former I used for QRO ops at my home ham shack; the other one with the BNC connector I used for portable QRP ops. I used some junk wire I had lying around for the radiators. The 9:1 UNUN's build quality is truly excellent and the purchase price is very reasonable in my opinion. I heartily endorse this product. Random wire lengths I have used with this UNUN are: 41, 65, and 71 feet. Note that 65 ft is in EFHW country on 40 meters yet works well with the 9:1 UNUN with 25+ ft of counterpoise (shield of the coax or a separate 25+ ft of junk wire). 65 ft also works very well for me on 75 meters with the counterpose. I have no financial arrangement with Nelson Antennas other than being a thoroughly satisfied customer. 73/72 de AE5ZX
Thanks for sharing... I like antennas like this. I've been quoting the following out of the Antenna Handbook Chapter 2 and this video fits the quote --- " Please recognize that an antenna need not be resonant in order to be an effective radiator. There is in fact nothing magic about having a resonant antenna, provided of course that you can devise some efficient means to feed the antenna. Many amateurs use non-resonant (even random-length) antennas fed with open-wire transmission lines and antenna tuners. They radiate signals just as well as those using coaxial cable and resonant antennas, and as a bonus they usually can use these antenna systems on multiple frequency bands."
This was my very first permanent installation antenna. I overloaded it once; the SWR went off the charts, and then the enclosure cracked. After I gave it some time to cool down, it worked fine. I've since installed his 1kw+ EFRW antenna, and it's a beast! I love Nelson Antennas! They are reasonable, have quick shipping, and are reliable.
Great video! I ordered mine a few weeks ago and have it in hand, just haven't had the time to put it up yet.
When you were standing on the roof we can see a transformer on the utility pole behind you. I would definitely make should that isn't your noise problem. Thanks for the video!
TeamReplay for the win!
Looks like a great setup. I feel ya on the noise floor
Dude, I thought my noise floor was high...wow. at 10:23 Going to look into Parks on the air in my area with an icom 7100 as my home station; using it as a portable speaker wire. Still learning this art with something new to learn every day.
Wow! Looks good! Thanks Mike for sharing...
You bet
Great video Mike! I ordered one after your last video. It's on its way to me now. 73, George K2WO
You might want to check with Josh Nass on that noise issue. It appears to be similar to his neighborhood's power line noise. He got the power company to come out and fix it.
Nice antenna. In addition to adding some glue lined heat shrink to the end of the wire, I would suggest that they paint those white "dog bones" black. That way the whole thing virtually disappears when put up. I do that on all my homemade antennas.
Hey Mike, nice video... My noise floor is pretty loud, I'm running about 175 of coax fm shack to box, I have it set up as a slope w/ para cord at about 30 feet to my 2m poll.
The box is about 4 ft off the ground, I have a choke, about 5" diameter w/ an excess of about 4 ft just hanging off... Should I take out the choke and just stretch out the coax?
One more comment Mike. Let me just send you a 65' 40-10m end fed half wave (no tuner needed) and the 80m add on resonator kit eh? Free of charge, just give an honest review?
If you send me one. I'll give an honest review
I have 2 EFHW antennas from Nelson. I bought an End Fed Long wire from Palomar Engineering. It works great, 155 ft long and able to tune on all HF ham bands.
I own 2 of those. One installed permanently as a vertical about 30 feet. The other for camp/POTA with various lengths.
Hey Mike. I have one of these. It's been in my shack never used for 2 years. 1st time last week I got it out and mounted it as a secondary antenna off our BBQ area so I can sit make contacts. THIS ANTENNA IS BRILLIANT. It actually out performs my centre-fed ladder line dipole - which is my main shack wire - off my tower !! I cannot congratulate Nelson more. Excellent. Love your review. Cheers. Kindest regards Mark, NSW Australia.
Thanks for sharing
Having a blast with mine.
Worked North east China today on FT8
Add to that Antarctica, Australia now and setup in less than ideal conditions with a wire fence on one side and plenty of wires on the other.
I actually have two, one in the car for parks etc. and a permanent sloper at home. I've had to move a lot in recent years and was able to get on air so easily.
I have the opposite problem, I’m down in a deep valley and struggle to get my 40m EFHW more than 20 feet off the ground and the antenna is nearly deaf. Low noise floor, barely any reception except a handful of NVIS stuff
I would add some attenuation to the radio with the noise level you have. It would help some at least. I think your rig can add 6dB or more with the attenuation settings
right? I know it's not the best way but it should help.
I just ordered this antenna. I plan to deploy the wire through a window, straight up the outside wall to an antenna pole then straight out to the back yard keeping the box inside my room “ie Shack”. Do you see any problem with that?
I love mine. I do primarily ft8 and the website says its limited to 25w digital. I have run about 60w with no issues. When i was driving truck i would through it up between trailers. It worked great. Now that im retired (thanks to Covid-19) i have the box inside my bathroom window (in the bathroom for my bedroom that we dont use) with 99' of copper wire in an L formation up about 8 feet. I can tune it all 160-6 but there are some spots in the 80m band that will not tune. I have a high noise floor on 80m. No idea why. Im going to hook up a battery and kill the ps to see if thats it.
Do you have a choke before the shack? My understanding is that there is a minimal amount of coax required for any given antenna length and a choke is needed. I would strongly recommend that you watch Palomar engineering's video on dipoles and the second part of his video goes into detail on this type of antenna. If the antenna wire is below a certain size it has a hard time tuning the lower bands. Once I recover from this surgery I'm going to try a 213 foot antenna though I might have to wait for the fall for the leaves to drop.
Please, can you tell me where I can but this antenna, again thank you.
maybe a silly question but whats the diference between end fed "random wire " and "the" endfed?
can anyone tell me what the wire thinger mabobs are at 1:20?
I know this video is a couple of years old, but what length is the wire?
Also, how many folks around you have solar panels for their houses?
Could this be used on my deck railing? Thats 25 foot high my roof is metal and I live in a apartment
nice video! so what was the actual length of the wire?
Thanks 👍 jaison terrific 💯 Job
Looks like there is a transformer on the pole behind the house. I wonder if that could be the source of the noise.
Feel for you on that noise man. Damn I’d be so frustrated. Might it be the electrical lines along the yard? Also, I feel my antennas makes the best efhw antennas. Even their non hw works nicely.
gracias Jeisom Micke ud es numero uno
Si!
I have 2 different 49:1 efhw antennas. They are resonant from 80m-10m. I do not have to use a tuner at all (wire is cut to 125' for 80 and 61' for 40m). The SWR on either unun is always under 1.5 (usually
Yes, it's not an end fed half wave but rather a end fed random wire antenna.
The one I got about a year and half ago was 50'. My 7300 tuned it pretty well.
I didn't measure it. It could be 50'
Im kinda stupid still for antennas, so the point of this build is to have the whole cable out in the open, or only the end of it matters?
Im looking for a solution, that i can use with my handheld on field, and both at home, even with SDR, but the problem is im on the 4th floor, but there is 0 chance they will let me use the top of the building for my antenna, so my only solution is the windows :/ In the capital of my country. So yeah, pretty bad chances, but i had a couple of success with mobile antennas already
Nelson made a great looking product .
If it helps ,NG9D has a video on finding bad transformers .
Great video Mike , I will never complain about my noise floor again 😞 If you want to get a tune direct with your IC7300 on 80m just try make your wire longer the length for End Feed random wire is not really random at all for the best results try these lengths 29 35 41 58 71 84 107 119 all in Feet. I don't know how long your house is but you said you thought the element was about 40' you seem to have room to extend it, if you could get 84' or 58' if not I think that will give you a tune on 40m and 80m. It wouldn't cost much to do do a tempoary extension and try it, before you try loading coils.
I was thinking about that but took the antenna down to send back to Jose. I'm getting another antenna from Nelson the is a 40 meter EFHW with an add on kit for 80 meters. I still like the idea of a 9:1 with a longer wire though and may go down that path eventually. We shall see.
How long is the wire, how many meters? Thanks a lot DL1STJ
looks like a Antron 99 in the back ground. great for 10,11,12 and 15 meters. 17 with a tuner.
Awesome dipoles, I bought that one the very first time, now I have the 1500 watts one works amazing DX everywhere from here Massachusetts I really recommended! 73 N1CRP!
Great to hear. I'm getting the 49:1 with the 80 meter add on. We'll try that out on the channel as well.
I ONLY use Nelson antenna (EFHW8010 in the park and EFHW4010 in the park (3x as much use) and have 3000 contacts since Sept 2021....and seem to get all those contacts form NY to Alaska, PR, CA UK.. and all with 50 watts on G90 and AT100 external amp...so.. I kinda say..IT WORKS... (49:1 EFHW)....these are all that I use...and seems pretty good....also support the shrink wrap on the final solder connection.. mine broke twice but that is because of my wrapping onto a spool..and accidentally using the WIRE as the anchor point...oops.. But, your mileage might vary.. I am only 3yr General license..so. I might be goofy...(and remember, your next car is gonna be an EV)...-KD2PWB
You should try a LoG for receive. Definitely improved things for me 160-20, but you do have a higher noise than me at S6-7 on 160-40.
Fantastic video, thank you. How do you take the coax into the house?
My pleasure. Thanks for watching. I just drilled a hole in the mortar and pass the coax in that way. There are also windows passthroughs as well.
The icom 7300 has a 10 to 1 tuner at 50% duty cycle in emergency mode. Wont hurt the raido.
After that vid Nelson Antennas should let you keep it, well done!
Hi, when it was mounted above your house what direction was it, north to south , east to west?
It's radiating east and west.
A bad power transformer on a pole nearby?
Hey namesake,
can't you use a QRM Eliminator for your malfunctions. great success has been achieved for malfunctions at home.
Greetings Mike from Almere the Netherlands.
Just a thought, could you not run your wire in a rectangle to get 160m-80m? Maybe some comapny would send you some fiberglass poles to test.
I really can't do anything but a dipole or end fed. I could do a loop on the ground for RX but that's about it. I have nowhere to put anything else up. Can't do (or won't rather) fiberglass poles either. I would love to put up my DX Commander but the power lines there are just asking for it to fall into them.
I got a my antenna 9 to 1 it did ok but requires a tuner, the efhw doesn’t require a tuner and worked much better. Of course it’s like 120ft longer.
Yes, I am keenly aware of all of these things.
How far off the ground at coax end? I just got one. (As a sloper)
It's horizontal at about 30' for the whole antenna.
Looks good need to get it out in the first get out of the city
KQ4CD Paul ⚓️
Hey Mike thanks for doing about the Nelson antenna it would actually fit in my backyard. My question is do you know the power rating? I have a 600 W amplifier I just wondered if it would be able to handle that. Thanks for showing the antenna I’m very impressed take care.
WD5ENH
Steve
Thanks for watching. The power rating is 150 Watts PEP so you would be fine if you are looking to melt an antenna lol! I don't know if he makes a high power version.
I have a QRO power handling unit listed. They are beasts ;-)
Use liquid Electrical Tape where the missing heat shrink is at the solder joint. That will do the job.
...noting that the 9:1 is 50 ohms to 450 ohms.. sooooo wondering why you can't dispense with the balun/matching xfrmer and feed it with balanced 450 ohm ladder line directly into a tuner? Have an MFJ that supposedly tunes balanced feeders...Seems to me all the xfrmer does is make it convenient to feed the antenna with 50 ohm coax.
Umm, because there are about 800 quintillion ways to make an antenna and this is just one.
Holy noise floor! Maybe it’s the transformers nearby or something? It must have something to do with your nearby environment.
K8MRD RADIO STUFF- How far should my insulator be from a tree?? I have one one connected to tree and insulator arrpox 12 inches from tree. Too close? Newbie here
It shouldn’t really matter at all. Not noticeably anyway.
Try a B&M folded dipole. 80 to 10 your tuner in the radio will tune it easily . I can also use it on 160 .
Hi Mike,
That's a well made antenna. Don't know if you mentioned it was rated for 150W.
I did in other videos
Lost me at the SO239 connector. For me, it's N type or not at all.
The fewer connectors you have, the less adaptors you need and the easier life becomes. SMA for small stuff, BNC for "scope (and IC-705) and N type for big power / outdoors stuff.
I just seen ya vid,what ya need is a carabeena on each end of ya paracord but also havin a tilt over base dyna bolted to ya chimney so ya will have a pole of say 3 or 4M on it u can use to hold up ur feedpoints
That's a good idea but I'd be hesitant to attache anything to the chimney. I've heard too many horror stories.
@@hamradiotube u could always use a sat tv dish mount and usin some 5mm steel plate weld a bit each side of the mount pipe and put a bolt through that and ya steel pipe goes inbteween and then at the bottom of the antenna support pipe another bolt goes through as a lock
Nice video Mike. Think you’ve got a bad power transformer close to you, real close. Power companies usually have a section that runs down interference like you’re experiencing. FPL in Florida does, might be worth a call. KM4SON
Also solar panels and smart electric meters!
...power line buzzies are a QRN pain... if you can find one, get a portable AM radio and go hunting. Noise tends to peak at line cross junctions... a sledge to bang a pole or two to see if you can note any change... lotsa times its hairline fine arcing down a corroded insulator that has a carbon pathway. That's why when it rains the buzzies sometimes go away, then return when things dry
been there, done that.
I used the nelson code to buy a 220 antenna!
sweet
Something you should know. You need a coaxial line isolator from my antennas read the reviews Air chokes and ugly baluns won't do it. It will cut about half or more of all that noise about 90ish $ you put it right before your radio and if you need more run another back to back. Good shielded coax helps and a 100ft coax is a great counterpoise for more bands and ALWAYS ground the coax to a great ground rod before it comes into the shack right outside not at the antenna.
Do this and it works like magic for all RFI
NO BS .
Chuck AA4CP
Well now you tell me!! I'm about to put up an 80 OCFD in hopes of eliminating some of the noise. EFHW's are notoriously noisy so I'm hoping that helps. My other EFHW at the house isn't as noisy but it's running in the opposite direction as the power lines. My coax is as good as it gets. Messi & Paoloni. All kinds of shielding on it.
Nice review. And nice 10m opening! 73 de K2CJB
Hey thanks Chris. It was a miracle. Playing with an awesome new antenna and 10 meters is open at the same time? That never happens. I even worked Costa Rica on 10 that day.
i like your tshirt icon
Mike, have you experimented with the 41’ 9:1 by mounting it vertical? It is pouring rain here or I would try it to see how well it works for dx.
Not Nelsons but I have done a 9:1 vertically yes. Works great. You can see it a little in the beginning of this video. This was before I discovered shooting B-roll lol. ua-cam.com/video/U1bqp3C3s9Q/v-deo.html
@@hamradiotube Awesome Mike! Thanks for the link. I will try the Nelson tomorrow. Hope to log you again soon!
Those power lines right behind your house don't help your noise level and I cold tune up on all bands, I did find that the antenna was a litle sensitive to where it was installed.
Tell me about it.
@@hamradiotube I need to find a ham in Cleveland GA. I'm thinking about moving to the area and the house I'm looking at appears to have an Electric distribution site about 200 yards away. I'm afraid that may cause some RF interference for me. I have a friend going by to check out the area tomorrow but he isn't a ham. All I have at the moment is a Google maps satellite view.
You roped your neighbor in on this? good for you! Everybody!!!! Make friends with your neighbors. Help them and they will help you. Be kind!
Also, would love to see how those feedlines enter your house. I only ask cause, I'm a crazy noob and want to learn.
I've asked before about surrounding metal objects ... will your other antennas have an affect on this new antenna?
Its simple. Drill a hole in the house. I talk about it on my next Monday Mailbag video that will be out this Monday at 12pm Central. Metal can and will have an effect on antennas but these are far enough away where I don't really notice any changes. Plus they are all going different directions which helps.
At 2:59 "...and this is the 49:1..." What? The title of the video says "9:1". Please un-confuse me.
It is a 9:1. I misspoke.
@@hamradiotube
We’ll let you get away with it THIS time …😂
i figured out where the Rf noise is coming from. i see an electrical transformer in your back yard. report the disturbance to your power company.
Why 9:1 why not 49:1 ?
When it's all done it's closer to 49 feet.
Try again. I left a comment but it did not show up. I was sending links for photos. Try without the link.
I have had this antenna for one year. The antenna is 71 feet and the counterpoise is about 25 feet. The reason for the counterpoise is that I have common mode choke next to the UNUN. A icom 7300 into a MFJ-939 tuner with 50 feet of coax up the antenna. It tunes from 160 meters tp 6 meters with low swr.
Yeah UA-cam doesn't allow posting of links. Your wire is a lot longer than this one. I tried a counterpoise and that didn't do anything. Though I just picked a random couple pieces of wire and soldered them together to see what would happen. Still couldn't tune any better. I'm gonna try another one of his antennas after HamCation so there will be more videos for Nelson Antennas.
Every Ham radio operator should constantly repeat out loud to himself: "The most important thing, idiot, are the antennas."
My knightly noise floor is insanely loud. In the 80, it was quite low. But it got worse over the years. After sundown, radio is worthless.
Turn off all your LED lights. Most are very RF dirty . Turn off every non crucial circuit in your breaker box one at a time while monitoring waterfall and see what circuits are throwing hash. Then start checking objects on those circuits such as led lights, TVs, appliances etc. Might have to run isolation RFI beads on those and your radio power cords to cut down on RF hash. If you can not find it in your house it might be LED street lights or bad Power company transformers..
been there done that.
Ugh! That's some bad noise floor you have there :(
have you tried switching everything off in your home to see if it helps ?
Every once in a while i trip my mains breaker and run the radio of battery to see what noise is my own and what is from out side.
See you on the bands. 73
been there, done that.
Btw that noise could be from a corrosion on ya powerlines right over ya fence
It could be many things. It comes and goes. I've had an RF Field tech out and couldn't isolate it to anything other than a crappy location.
It might be worth goin for a walk with a radio,ive got constant noise unless the power goes off in my suburb but ive found noise peaks every 25M but its quiet inbetween
Its 43' mm Mike. Ive got one.
To test the antenna you must not use a tuner. This is ment as a non tuner antenna.
That’s not the case per the description on his eBay listings….
2:58 - No its the 9:1 , isn’t it? 😉
Need to waterproof your coax connection to the box
Yeah let me do that for an antenna that I'm reviewing and then taking down.
The good: They work awesome. The bad: weak housing box. Better boxes would make a great system bulletproof.
Meh, you can't please all the people all the time. I think it's plenty fine.
Please please do a video of how to set this up for an apartment.
you may have a drug house in your area with that interference. I've been dealing with that with FCC for two years now with no help.
Grow lights 😂
Is this on ebay? And by the way, if my wife asks, I going to say that Mike forced me to buy it.
Per the several times I say in this video, yes, this antenna is on Ebay.
Dude, I'm curious, Why do you hate cops?
No wonder you go portable in so many of your videos.... If I had that noise floor, I'd sell my equipment.
Yeah
I would guess you have a bad service transformer close to your house, call the electric company to do a study, or find a battery operated am radio and walk to each transformer and you may find your noise.🖐🏻73's🎙🎧 KD9OAM 📻
Never have I seen that much noise. You poor man.
I’d move!