Ham Radio - My second HF antenna. A stealth end fed wire for 80 - 10 meters
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- เผยแพร่เมื่อ 8 พ.ค. 2017
- I needed a second antenna for experiments and dual monitoring. Decided to try a stealth design.
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Hit me up on the echolink repeater down by my house: W9TE (Node: 519521) - วิทยาศาสตร์และเทคโนโลยี
Two things... You should be aware that there is (usually) high voltage at the end of the wire, and you should make sure it cannot arc to your roof and start a fire. ALSO you might try putting 5 or 6 toroids on the coax that feeds your unun. That might keep more of the RF out of the shack.
Excellent video I like how the antenna worked on my favorite band 40 Meters! 73 from KC9QVE Gas City,Indiana
Love that video and antenna idea Kevin! Thanks brother! 👍📻⚡️
Great presentation, many thanks for sharing.
Thanks for the videos Kevin! I enjoy watching you.
It looks like you have metal gutters around the roof very close to your antenna wire.
Very informative. I have the same radio, a classic.
Kevin, I lived in apartments for years. I have used this type of antenna in every configuration you can imagine. I was mostly stuck on 80 meters until I got smart. In older buildings, I used the screw on an outlet or a water pipe. I finally ran a counter poise around the base boards or outside like you did. As you say, you have to have somewhere for the return path of the RF to go. When operating like this, the counterpoise is more important than the antenna itself !
So, this is really just a dipole, not an end-fed.
@@denelson83
that's exactly my thought too.
@@denelson83 He was going for a “non-resonant” antenna length though, to use it as a multi-band antenna. Not a balanced antenna.
Kevin, Thanks for the great info. New ham here just got my tech and general ticket 3 mo. ago. I have been running on 70cm on a baofend hand held with a homemade J-pole. I live in a HOA and I'm going to put up a end or DX Commander vertical. I have about 100' of roof eves to run the antenna. I just purchased new ftdx10 and a used MFJ 949e tuner really looking forward to getting a base unit setup. KN6Tux 7 3
I have a soft spot for the end-fed wire, it's presently my main aerial in our small garden and 14 metres of wire does the business on all bands from 60 mtrs up to 6 mtrs. I don't even use a feeder, the wire and counterpoise come in through a small hole (25mm plastic pipe) in the wall of the spare bedroom, and hook straight onto the KX3. I do have a vertical as well, 20 feet aluminium tube in the garden, but the end fed does the main hauling.
I enjoy the YT videos Kevin. Well done. Hope a job shows up for you soon. 72/73, Les g0nmd
Thanks for watching Les. My main antenna is another end fed. You may have already seen that video. It's about the best all around solution in any limited situation.
@@loughkb I have moved to a different part of the country so this antenna might be up my alley. I didn't notice remember hearing what gauge wire you used on both parts of the antenna. Thank you in advance! I am a new follower and loved this video!!
73
KJ6IHZ
Thank you, Sir. Well explained and highly educative.
I'm running one of these as my main HF antenna from a tripod on top of the house to my only tree out back. Mine is roughly 63 feet long with the feedline acting as the counterpoise(shield grounded as well). I get roughly 4:1 on 80 meters, 2.5:1 on 40, then 1.5:1 or less on the higher bands with no tuner. Of course I use a tuner to bring them all down to acceptable levels. I'm planning to build another.
+KD9EAS adding an actual wire counterpoise of half the length or more will help it and get some rf off your coax
Great job Kevin! I am always amazed to see how little noise you have at your house overall. If i were to run an end fed in that fashion, i would have S9 of noise. 73
I've done a lot to reduce noise. I've wound my ethernet runs around torroids at the ends, the same with wall wort power supplies where I couldn't eliminate them. The netbook computer at my ham station takes 12V power on it's input, so it runs off the same linear supply as the radios. etc. I still get hash from neighbors TV's though.
Toroids! Many hams use them but never say which one they used unless they are describing a kit build. I never know which one or ones to order. Kevin can you help with that? Do your neighbors have plasma TV's? The wire that you've used for the two end fed's is stealthy. I wonder if you've considered a loop. From pictures you've shown from your first end fed it looks like you could put up a 40m loop and still be stealthy. Are you being stealthy due to neighborhood restrictions or city restrictions?
Hi Terry, No, no restrictions in my hood. However, I know many have them, so I was showing a way around it. For the UNUN I used T50-2 powdered iron core torroids. The noise elimination projects required larger diameter, almost 2 inch versions.
Okay Kevin, thanks. I thought I had a book on toroids, an ARRL publication. I can't find it. Must still be packed away from last move 12 years ago. Probably why I'm so dense about toroids. Hi
I like your videos. I had a license back in the 60's and early 70's. My call sign was K3MSX. I am studying to take my test in February. I also hope to get my old call letters back again. Your videos are a great break from my study time. They also keep me motivated. Thank you. Tom [ at one time K3MSX] 73's Update, I am now a licensed Ham with call letters KC3MZP. I have applied to get my original call letters back. The FCC said that they were available.
Just waiting now. I also purchased a I com 7300. Again, 73's, Tom 😊
Did you end up getting your original callsign back?
@@colonial345 just checked and as of 1/2/2024 he did get K3MSX, congrats to MSX for gettin his sign back. 73's - KO6BBM
That was interesting - Thanks!
However, since I have around 2 acres and no one to complain I don't have to worry about stealth! LOL
I have an OCF Windom and have a bit of a problem getting a low SWR at 3845, I think I have a flaky antenna tuner. Busy cleaning and re-arranging the shack this week, but plan on working on it more.
I wish I had space, and trees.... With that kind of room, I'd put up a full wave loop!
Thanks for watching.
Kevin, you might want to set up a test bad to compare antennas. Have WSPR set up to switch between two (or more) antennas every five minutes. Since the propagation isn't likely to change that much in a few minutes, the coverage you get from each should determine which is better and even which is better in certain directions and distances.
Hi Kevin, thanks a bunch for this video. This and your other video on your end-feds have given me hope that I can make an end-fed work on my small lot. Hopefully this summer I'll have the time to put it up.
Quick newbie question, though: If you have a random length of wire and a similar length counterpoise, how is this electrically different from a dipole? What makes it "end-fed"? If this is too big a question to answer in TH-cam comments, feel free to ignore me. :) Thanks!
When you said roundabout 3 minutes in that the turns need to be nicely parallel, that got me thinking, Kevin. When I was making mine a year ago, using the exact same schematic you have with the blue red and yellow wires, it kept unraveling and I got very very frustrated with my (lack of) handiwork. My daughter was on vac from uni so I asked her to plait the three wires together, which meant that winding the toroid now became just one action and was easier to wind for klutzy me. It has worked perfectly like that for a year.
BUT as I said, your comment got me thinking, and I posted on our local forum asking if the parallel vs plaited wiring would make any difference to the performance, and 2 out of 2 answers so far say "no". I'm not saying those are definitive scientific answers, but it might be that keeping the wires all nicely parallel may not be worth the effort, and certainly in my case I would never have finished if I was being graded for neatness, hi.
I'd be keen to hear your and others' comments on that.
Great video: one of the better ones I've seen. Well thought out, well presented: kudos.
73 de Jim ZSJMB in Johannesburg, South Africa.
Oops: ZS6JMB not ZSJMB
I know of one local guy who just wrapped them around. The wires crossed over each other a few times and it looked a bit messy. He'd used stranded wire. His performance wasn't great. It worked, but he had a hard time tuning it on a few bands.
He re-wound it using solid wire. (solid wire is easier since it keeps it's shape as you bend it around the torroid) He also kept it nice and neat, similar to the drawing.
It tuned up easy on all bands and his noise floor was a bit lower. That latter point could be other factors though.
great job 73s KF5AXY
When you get through playing around, try an old offset feed Windom from the 1930s. Works from 80 down through 2 meters with NO tuner. I've even ran a CB off of it ;) SWR rarely above 1.5 on any band. If your finals can't handle that, you need a radio first :) As to RF in the shack, I could care less! I can hold 200 watts LOL! Use to work on an old Comark and RCA television transmitter with 1 megawatt ERP (were talking twin Klystrodes). So much RF in the building the florsecent lights always stayed lit!!!! RF off a radio? That's a non-starter. AE4YW
This was awhile ago. I'm now living in an RV and traveling around. I've settled on a 120 ft. doublet as my main antenna. Possibly the best and most agile wire antenna I've ever used.
"Honey it's really cold and the heater is busted what are we going todo." Cranks the house antenna to 400w.
I am new ham living in a neighborhood where a stealth antenna is the answer. Thanks for your clear and concise explanation on how you built your antenna. I have looked at multiple plans for a 9:1 UNUN and none of the plans I have found have a listing of a part number or size/type of torite to use. I have a 100W transceiver, can you provide me with the part number, size/type of torite to use?
Go have a look at my video on winding the 9:1 unun. I think I linked the page where you can buy them in the video description.
Madison Indiana here and I really like this video. Do you have any opinion of how it would effect this it put in a townhouse style second story attic ?? height good ?? bad ??
To make it even more 'stealthy' use aluminium welding wire for the radiator. When it's up there, YOU won't be able to see it and YOU know where it is! WITH GOOD BINOCULARS!
U want some fun a 70 cm moxon antenna is a good build for the ft 817
Thanks for this informative video. I am installing a BBTD whole house antenna as shown on the HFLink website a Bonnie Crystal design. I'll have 190ft of wire and it will all be out of sight. There is a 1000ohm terminating resistor at the midpoint and a 16:1 Palomar Engineering Balun at the feed point. Do you use a common mode coax filter on this rig?
Hey Kevin, how did you decide on counterpoise length? I have a 30ft End fed I use on 40-10m, I also have a counterpoise wire, but unsure of exact length (rougly 12ft). Seems to work well, tunes up fine on manual tuner.
Ideally, it should be about the same length as the radiator. I just used the space I had.
First, I want to say how much i appreciate your videos. They're very well done, and because I'm recently unable to work for a time (it's been a month already, going to be out another month at least), I like the fact that everything you show is a great example of "what you can, with what you have." I first got my Tech in 2012, fell out of the hobby, and came back about a year ago. Started SWLing, and now have my General. I built a 9:1 unun last summer to see if it would help receive when I was listening with my RTL & long wire. your video has me curious about using that same antenna for transmitting. What gauge wire do you recommend for the 9:1, and with that given gauge, what would do you think the power rating would be?
Thanks, & 73 DE KD2CXU :)
+Bullfrog89 I'm using doorbell wire on my unun, not sure of the guage
It has no problem at 100 watts.
In case anyone else is interested, I just looked it up. Looks like 20 gauge is most common door bell wire. Also saw a couple references to 18 gauge.
Oh, sorry, I did go look at the spool last night. It is 20 gauge.
Thanks for the video.
How did you get google maps to draw a straight line from your location to the other stations location.
I used Google's measure distance function. Search for the other stations address, and in the map that appears, right click on the station and select measure distance. Then go click on your location, and it will draw the line and show the distance.
Got it.
Thanks for the tip
I'm a little confused on the counterpoise wire does that need to be grounded or just ran along the ground anywhere or does it need to be ran along the ground underneath the antenna in the air and should I ground the counterpoise to A rod in the ground
Brilliantly informative Kevin, especially for newcomers like myself. Would this type of second antenna be useful for an sdr type receiver used together with my g5rv or would the output on the g5 when transmitting be too much? MW6WHL
You could damage your SDR. You'd need a way to ground the SDR's antenna input when you're transmitting, to protect it from the transmitted RF coupled back to the receiving antenna.
Thanks for the heads up, Kevin. So how does one use an SDR with a transmitter? Is grounding the SDR input when Tx the only way? Also, logged into 519521 earlier but nobody about. Hope to catch you soon. Great videos too by the way, I find them very very informative, so many thanks for taking the time to make and upload them sir. MW6WHL
You could use a double pole double throw relay or switch as a transmit/receive switch. It could both switch the antenna between the SDR and the transmitter as well as ground the antenna input to the SDR. If you use a relay and your transmitter has some sort of keying output plug on it, you could automate the switching.
Hi Kevin - have you ever tried more than one radiating element when using a 9:1 unun? I wondered if it could be made so that the second element is tuned for a different band, similar to a fan dipole concept? I have no idea if this would work, but would be interested to hear your comments.
I think it would work fine. Just like in a fan dipole, the RF is going to choose the element that provides the best match/load.
Had a friend that used to come over her neighbor's toaster (literally) back when the CB craze was on in the 70s :) Person thought their toaster was possessed at first lol. Also another neighbor's hearing aid (bahhhd!).
AM is the most notorious mode for such stuff. I used to hear a neighbor on my electric stove years ago. The contacts on the heating elements were dirty enough to act a little like diodes and rectify the audio out of the RF.
Unfortunately spurious emissions are the norm for unapproved equipment commonly used on CB bands and 99% of those folks have no idea how to rectify the situation (and some don't care). I did plenty of that BITD before i discovered ham. A neighbor of mine came through my SS guitar amplifier, with it unplugged. No telling what my voice resonated on-from my mobile setup of the 90's. Now of course, we talk much much further, more reliably, with less power (and no superbowl).
I'm testing a 9:1 balun that i made with an antenna analyzer. Can i use 'any' type of 450 ohm resistor or must it be a carbon non inductive type?
Non inductive.
GEEEE HOW MANNY BNC ELBO CONNECTORS DO U HAVE ON THAT FT 817 BATMAN
+jerome grzelak let's the cable come from the rear.
Yes thats the best way hi hi kg6mn
Kevin - How does it transmit on 80m?? I need something for that band and don't have the space for anything like a dipole or other tuned antenna on that frequency.
Not too well, but that makes sense since it's a somewhat short antenna at those frequencies. A longer end fed wire would work better, if you have any trees at all on your lot and can run something straighter upwards.
No trees unfortunately, I could run around on a fence and some hedges for quite a ways. I don't know if that would work. Can it go around 90 degree corners? I figure the best I can do on 80m is NVIS. There's simply no way to get it up to even a 1/4 wave length.
What software were you using which produced the map with the line drawn between your contact and yourself? Thank you for your help. I appreciate any help which you can offer.
Google maps. Right click on one spot and select "Measure distance" from the menu, go and left click on the other spot.
Thanks. God bless.
From an SWL’ers point of view, is the counterpoise needed?
Richard Coward
For SWL? Probably not.
Ham since 1958. Listener since 55-56. Pirate since.. I'm not telling you!
Would you be willing to tell me the lengths of antenna for 40 through 6 m I have limited antenna experience with end feds
I've experimented with a lot of things since this video was made.
Lately I'm a big fan of the end fed half wave design using a 49:1 match at the feed point. A half wave wire for 40, about 65 feet, would do what you ask.
Occasionally?..... Im always wanting to monitor 2...or 3....or 4 frequencies 😁
I have a metal roof. Would the metal preclude building an antenna inside the attic?
Likely...but then I'm not antenna expert.
What were you scanning for to tell if the band was open? A beacon?
People transmitting anything. 👍📻⚡️
@@Tommy_Boy. get into digital modes, you can just call CQ on say, JT8 and then check the online sights that report contacts.
thats a nice radio..440?
Yep. It was gifted to me in a hardly working state. If you go way back a year or so in my videos, you'll find one or two where I repaired it. It works perfect now and has one of the best receivers I've owned so far.
What wattage are you running on this set up?
Usually less than 30 or I'd start annoying my son by buzzing on the TV.
Why not feed it in the middle?
that configuration is more dipole then endfed.
will this work with a metal roof
Probably not very well if the wire is at all within proximity of the roof. You generally want to keep your antenna wires a fair distance from large metal things.
The best receiver is computer spkrs kg6mn
Hey Kevin, thanks for an inspiring video! Question for you and/or other hams - How do you think the performance of this end-fed 9:1 UNUN antenna would compare to a Broadband Butterfly Terminated Dipole (BBTD) using a 16:1 BALUN with both ends tied together via a 1200 ohm resistor? That antenna can also be wrapped around the edge of the roof (credit to K4SFC - th-cam.com/video/a-vbdO-mUDM/w-d-xo.html) I'm trying to decide which one to try first. Thanks very much, Greg KJ6ER