W8TJM

Пікірлер

@bduff5004 16 күн бұрын

Great explanation thank you. I am going to attempt this. N4STS 73

@gam67 26 күн бұрын

If you ever decide to sell the 10m version, please let me know. Unfortunately, I can't build antennas myself.

@W8TJM 26 күн бұрын

I did sell two of them locally. If you can find someone still stocking the MFJ Moxon, that is a pretty good deal at 160 USD.

@gam67 26 күн бұрын

@@W8TJM I'm very interested in your design. If you have one available for me next time, please let me know. I'm not in a hurry.

@skyl4rk Ай бұрын

Do you think there would be an advantage to angle the driven element up to increase the takeoff angle?

@W8TJM Ай бұрын

It seems keeping it horizontal works the best. You might try modeling it with EZ Net to see what you find. Usually you want a low take-off angle.

@user-bq5yz5fu1l Ай бұрын

Дуже гарне виконання, креативний підхід! 73,DJ5RG=UR5RG.

@Gabaab Ай бұрын

how does this compare in losses to a decent autotransformer or "unun" like 49:1 commonly used for end fed antenna?

@W8TJM Ай бұрын

Quarter wave transmission lines are extremely efficient so the loss is extremely low. No ferrite or winding coupling losses to consider at all. Big disadvantage is that it is single band, but it does give you the most efficient half-wave antenna possible. Those 49:1 all band solutions are a compromise, but they do work once you tune them in.

@Gabaab Ай бұрын

@@W8TJM i will try one for 10 meter band honestly, lower frequencies seems like too much hassle adding the extra 1/4 wave twin lead makes things much longer and unwieldy. do you have the correct 10 meter measurements?

@W8TJM Ай бұрын

@@Gabaab Send me an email on my QRZ.com page and I will send you the most up to date dimensions.

@nickkendall3764 2 ай бұрын

Grate video I look forward to more from your new channel you did a grate job antennas are one of people's main obsessions in radio me included I look forward to more

@harryszwergstatt2879 2 ай бұрын

Very good ! 👍

@W8TJM 2 ай бұрын

Thanks Harry! Hope to see you on the bands.

@harryszwergstatt2879 2 ай бұрын

@@W8TJM Maybe with this antenna ;-)

@harryszwergstatt2879 2 ай бұрын

Amazing! A really good antenna solution!

@JohnMcIntosh-io3fe 5 ай бұрын

Just built this antenna and put it on the air. First contact was New Zealand, 8449 miles. Easy to build, and works great!! Thanks for sharing this plan Toivo

@genoa1979 5 ай бұрын

I want this for 17 meter 😊 good proget IU1RZX 1AT227 livio

@johnsonstechworld 6 ай бұрын

Nice video. Hope to see you on band some time. 73 de VU2JO

@W8TJM 6 ай бұрын

Thanks Jon! Would love to work you this summer as conditions peak. Take Care and keep having antenna fun!

@johnsonstechworld 6 ай бұрын

@@W8TJM Sure!

@martindavies6640 6 ай бұрын

Hi could you please give me the wire length for the driven element in feet and inches,and also the reflector best regards Martin

@W8TJM 6 ай бұрын

Those lengths are in the video under the wire assembly instructions in meters. In inches, the reflector is 194 inches long and the director halves are 91.3 inches long. I hate doing English conversions so always use metric. 73

@barrygkx 6 ай бұрын

Great video. I really enjoyed it. Easy to follow instructions and some neat tips along the way. Barry, KU3X

@W8TJM 6 ай бұрын

Thanks Barry! Coming from someone as experienced as you, that is a big compliment. 73, Toivo

@michaelrogers3078 7 ай бұрын

Your video is interesting, your presentation skills are quite good, and your video production is very good. Well done! 73 N4MJR

@DK5ONV 7 ай бұрын

That Moxon is a beautiful Antenna and works great

@W8TJM 7 ай бұрын

Thanks Guenter. I've been surprised how well it works only 6 meters off the ground. Just busted a pile-up with 8G15S in Indonesia on the second call! Hope to work you soon.

@14KiloWhisky 7 ай бұрын

Nice 😃

@lilbump406 7 ай бұрын

Are there any gains from this design over the normal rectangular moxon?

@W8TJM 7 ай бұрын

Modeling it with segmented arcs, it behaves like a rectangular one with slightly more forward gain and a more complicated back-side pattern. I've been super happy with how it has worked out with practical on-the-air performance, as it has gotten me to 166 countries worked, mostly on phone, from an HOA.

@trevorhaines2274 7 ай бұрын

Hi Toivo. I think your design is very clever. Re the interlacing affecting 10m VSWR, given you have seperate coax feeds, why not lift the 10m antenna higher on the mast to get some vertical seperation to the 15m antenna. I’ll bet as you lift it there will be a point where the VSWR starts to return to levels like the independent readings you got. Worth a try? Cheers Trevor VK3DCQ

@W8TJM 7 ай бұрын

Trevor... That is a solid suggestion! I think it would indeed get the antennas to be a bit more independent. Only negative is that it adds weight with the additional boom and bits needed, but it is certainly worth a go.

@jasonash9121 7 ай бұрын

This is such an excellent video, Toivo. Bravo. I've been poring over your video on the 10m Moxon in recent days, and gathering parts I will need to replicate it. My wife keeps asking why I would ever need four fishing poles when I don't even fish. Now I fear she might be wondering why I am burying a PVC pipe in the yard and very delicately snipping bits of wire of the end of a ladder line in the driveway. I'm so grateful to have HAM operators such as yourself providing such valuable information on KZfaq. In my small community, I don't have any elmers to lean on, so information provided by those such as yourself is invaluable. Cheers and 73. Jason W2ASH

@bg7jaf 3 ай бұрын

For making moxon antenna I bought a lot fishing poles and after that I am fishing man now😂

@foxman362 7 ай бұрын

can i make one theses for 11meters.

@W8TJM 7 ай бұрын

Sure. Just make the wires a few percent longer.

@shortwavesurfer7222 6 ай бұрын

Hi Toivo Excellent antenna build!...I am currently using a single element 10m elongated rectangle loop and it works great...have been thinking of converting it to a moxon using the same footprint..your video is motivating me to do that👍 73 Steve W8SAW White Lake

@jasonash9121 7 ай бұрын

Great video. I'm curious as to what kind of rotator you are using. I've priced a few and they seem pretty expensive. 73 W2ASH

@W8TJM 7 ай бұрын

Thanks for the compliment Jason! I bought the RCA VH226E rotator two years ago and have been impressed with how well it works. It is around 120 dollars at Amazon and 109 dollars in other places. I have given it a lot of use and no issues. The push button direction setting is very convenient. For light antennas mounted close to the rotator, it should last quite a few years.

@jasonash9121 7 ай бұрын

@@W8TJM Thanks for the quick response. The price on the VH226E isn't bad at all, especially considering how expensive some of the HAM-specific units are. I think I'll pick one up when I try a Moxon build this spring. Cheers and 73. Jason W2ASH

@imoldovan 8 ай бұрын

Has anybody eznec these different arrangements?? I am curious to see how the results differ from actual measurements.

@W8TJM 8 ай бұрын

Analyzed them (21 segment arc approximation) before building them and the performance is very close to a normal rectangular version with some parameters life forward gain actually better. Turns out the length of the elements is more important than the shape.

@wildbill1 8 ай бұрын

Thanks for the video. Great job too!

@W8TJM 8 ай бұрын

Thanks! 73

@kf7bws 8 ай бұрын

For two and a half years I have used a fixed Moxon at 68 deg 20 feet off the ground for 20 meters. I have worked from New Zealand and Australia to Greenland and Finland, Indonesia, China, Japan, East and West Russia, Europe, Africa, North and South America and all 50 states. I am convinced that the Moxon Antenna is the best simple wire antenna available for hams. You have inspired me to remake it so I can rotate it. In all I have confirmed 76 countries, 6 cotenants, all 50states and 730 US counties. Thank you from KF7BWS.

@KP68videogates 8 ай бұрын

Very cool. I love to see this. Nothing wrong with buying station equipment, but building what you need from materials you have on hand is what it's all about. Thank you for sharing sir.

@DXingTV 8 ай бұрын

Thanks for the informative video. Could you give me some specifications on the toroid that you used for the choke please. I will need to order one in. Thanks, Frank VK4FEM

@W8TJM 8 ай бұрын

I normally use 12-14 turns of RG-58 on an FT240-31 toroid for 20 meters, and 10 turns of RG-58 on an FT240-61 for ten meters. 73!

@W8TJM 8 ай бұрын

Frank.... Also, Google "G3TXQ chokes" and you will find some charts on how to select the best torroid for a given frequency and coax.

@che59v 8 ай бұрын

After years of trying out simple antennas the one element delta loop topped them all, not to mention the big decrease in QRM.

@W8TJM 8 ай бұрын

I am a big fan of delta loops also, but they end up being a bit too large for the area where I live. Had one back in 2015 and it did indeed work well.

@che59v 8 ай бұрын

@@W8TJM Too large on 10m band? should be more or less the same size (had them both on the same pole, not at the same time that is, lol) but then again, what do an old radio ham like me know, lol Anyways, the delta loop was fed as a vertical and most times did much better than the Moxon without the need for rotator. Enjoy Ham radio testing is all part of the fun.

@Labatts22 8 ай бұрын

Great job!

@michaelrogers3078 8 ай бұрын

I really like your design, and your video making skills are excellent. 73, N4MJR

@W8TJM 8 ай бұрын

Thanks Michael. I finished this one up fairly fast so appreciate the comment!

@dougtaylor7724 8 ай бұрын

That is the easiest Moxon to build and acquire parts I have seen. Nice work!

@W8TJM 8 ай бұрын

Thanks Doug! It was a fun project.

@MirlitronOne 11 ай бұрын

Just discovered your channel, but this video ticks all the "yes!" boxes for me, especially the benefits of the half-wave vertical and the use of the excellent RigExpert analyser. Nice clear explanations too, no fluff! Oh, and adopting the metric system makes wavelength conversion easier... 😉👍

@eduardopower5254 11 ай бұрын

Great design but I think you said "I used 3 telescopic poles" I think I need 4 right?

@W8TJM 11 ай бұрын

Ah ha! That does sound confusing on the video! Should have said: "I used FOUR 3-piece telescoping fishing rods......" So yes, you need four of them. Thanks for the comment. It is a very worthwhile project as it works so well when mounted at modest heights. Mine is normally at about 16-17 feet. 73 -Toivo

@kennethblackwell1137 Жыл бұрын

Great looking antenna. Lightweight and physically manageable.

@dougtaylor7724 Жыл бұрын

Excellent presentation!

@KWHaraburda Жыл бұрын

Very clever design. I am going to take this idea and improve on it I hope. I would like to reduce the weight. It looks like the antenna does not line in one plane, but droops down on the sides near the 2 separators. Is it safe to assume this did not affect the performance?

@W8TJM Жыл бұрын

There is very little change caused by the shape or the droop. Have modeled it quite a bit and used it extensively. I like your idea of making it lighter, and I have been looking for plastic channel material for the boom and rod supports as well. Have fun with it!

@don_n5skt Жыл бұрын

Thanks Chuck. Really looks like some fun projects.

@DK5ONV Жыл бұрын

I am really blown away. I put this Antenna on my personal DIY to do List. Tnx for sharing. 73 & happy Humpday de Uncle Günter 💯👌🙋‍♂

@W8TJM Жыл бұрын

Danke for the comment! I will email you some further detail if you would like.

@DK5ONV Жыл бұрын

That Antenna looks sweet. 💯👌

@K1QS_Radio Жыл бұрын

Best vertical video everrrr! Seriously. Nice to keep it simple. Thank you and 73. K1QS

@franciscolopez3229 Жыл бұрын

Can it also be done for 10 meters?

@W8TJM Жыл бұрын

Moxons work very well on 10 meters, so yes, absolutely! Use the formula at the 5:15 mark for the driven element and the spacing should probably be a bit under 7 feet. Make the reflector 5-6% longer than the driven element.

@franciscolopez3229 Жыл бұрын

@@W8TJM Wow, thank you so much sir. You see, I am just new to hf starting with just an hr2510 and a rotary dipole. All the best to you sir and your family. 73s, DW1QEW.

@aarongriffin81 11 ай бұрын

@@franciscolopez3229 If you have a dipole, you can add a homemade reflector that is 5% longer than the dipole and 7ft away from it. You can also, add a director that is 5% SHORTER than the driven dipole and placed about 7ft in the opposite direction as the reflector and you then have a 3 element yagi. I built mine with romex wire inside pvc pipe mounted on a 12 ft 2x4 board. It is fastened in a tree and barely visible. Multiple antennas with an antenna switch act as a rotor.

@stylerxxl1 Жыл бұрын

i have already tried several j-pole antennas. unfortunately, i found out that the adjustment to the ladderline results in a significant loss of power. the only question is how much ;-) 73s de DL9HD

@W8TJM Жыл бұрын

Transmission line matching has very low loss so wondering where your losses may be occurring?? Currents are low everywhere except the shorted end which has minimal length so resistive losses are negligible. Mismatch loss should be very low if you do get the right tap point, matching section length, and resonant half-wave length. (Those are important.) I have found these antennas to be very efficient.

@kennymanchester Жыл бұрын

I stumbled into your video over a cup of Joe this am. So glad I did. I am smack in the middle of half-wave vertical experiments. Right now, end fed half wave graound mounted vertical feed methods are on the agenda. Looking to evaluate QRO opetions for convenience and efficiency. Coupled air core vs toroid core, vs tapped, vs difference capacitance options. What a blast I am having! Once I have my answers, I'll move to phased verticals using the results of previous discoveries. Anyway, I have a couple of questions: do you have any idea how much power this matching method will handle? I presume, full legal limit HF. I am curious if you've tried matching .05 wavelength instead of a quarter wave? That .05 Lambda length keeps popping up on me, and I'm just wondering. Also, do you notice considerable variation when antenna is closer to ground, say 1 Meter? I suppose you want to perform tuning at the actual location and height since tap point may change. I really enjoyed your presentation of this project. Thank you for sharing! 73, Kenny, NZ5i

@W8TJM Жыл бұрын

Kenny, Thanks for the comment and glad to hear from another antenna experimenter! I run a kilowatt with the antenna but have to be careful on wet days. The end of the matching section is very high impedance so the voltage there is in the thousands of volts. I have had arcing with sustained corona at that end, so I normally try to insulate the un-terminated end of the matching line and bend it away from the terminated end. I have not tried .05 lamda matching as I don't think that will transform to the extremely high impedance at the end of a half wave radiator. Also.... The antenna SWR is not very sensitive to height above ground, although the take-off angle does change.

@kennymanchester Жыл бұрын

@@W8TJM Very good to know. I guess weatherization needs to be a consideration to take seriously if operating in the wet weather. I am very curious how this feed method stacks up in the efficiency / bandwidth dept? This is turning out to be a bit of a shootout of sorts. No single method of coupling high impedance to low seems to be perfect. Each has pros and cons, I'm discovering. Anyway, thanks again! Great video

@W8TJM Жыл бұрын

@@kennymanchester Main disadvantage is that it will be a mono band solution. Efficiency is maximized with the transmission line method as there are no ferrite losses, and no mis-match losses. It is tuned resonant matching schema for a single band. Have fun with the shoot out and let me know what you find out. 73, and thanks again for the comments.

@kennymanchester Жыл бұрын

@@W8TJM Yes, a mononband solution is ok. It will be interesting to see how this match plays next to a air core, coupled LC. One more question comes to mind; what happens if we "roll up" the matching section and and place it in a box? A couple of the L-C combos I am messing with use coax for capacitance. Once it's cut, it can be folded up and put away. Of course this is not the same thing, but still wondering if the stub section can be bent with some tap/length adjustments to compensate?

@W8TJM Жыл бұрын

@@kennymanchester The matching section needs to behave like a transmission line, and it can have gentle curves or sags in it. Coiling it would cause it to couple to itself and its behavior would change drastically. It can tolerate some bends so experiment with it to see what works/happens.

@DARTHDANSAN Жыл бұрын

Do you use a tuner for this ?

@W8TJM Жыл бұрын

No tuner. SWR is 1.08 to 1

@DARTHDANSAN Жыл бұрын

Nice

@imarunner2 Жыл бұрын

I just found this video. Very interesting... have you modeled it? I wonder what the model would show. Does it appear to have directionality? How does it compare to other antennas you have experience with on 10M? Thanks for the video.

@W8TJM Жыл бұрын

Modeling shows it to have a much lower take-off angle than a horizontal Yagi or Moxon at the same height. It is the best 10 meter antenna I have used but a bit awkward to rotate. Keeping it fixed on Europe in the morning seems to work out well. Definitely is a directive antenna as it greatly attenuates signals and noise from the back side.

@dghuss Жыл бұрын

How much power will it handle? Thanks very informative on the 1/4 matching

@W8TJM Жыл бұрын

I use it regularly at 800 watts. The Common Mode Choke may saturate above that power. High voltages at higher powers also need to be considered as the bottom of the radiator is at a very high impedance.

@k0rc Жыл бұрын

This is a good, succinct video describing your installation. It's nice to see all the DX you have worked on SSB which helps confirm the radiation effectiveness, even at a couple dozen feet off the ground. 73 de Bob - KØRC in MN

@satelliteowner Жыл бұрын

Could you give some details on how to feed it from the end ? I am interested on the idea.

@W8TJM Жыл бұрын

The concept is explained here on this video. Send me an email per my QRZ email address and I can send you exact dimensions. 73. kzfaq.info/get/bejne/hdijZdyry52Vp4k.html

@satelliteowner Жыл бұрын

@@W8TJM Thank you very much 🙂

@b0r4t 7 ай бұрын

@@W8TJMI'm interested in building this as well, would be nice to have dimensions listed in the info for this video.

@jomf8929 Жыл бұрын

Nice work. very effective and simple antennas, especially for single-band dxing. I have a 15M version and it is simply fun to use -- your installation method on fiberglass poles is simple and effective especially for portable ops. It can handle legal limit too !

@9w8zzkmohamad59 Жыл бұрын

Thanks for the sharing mate. If use 300ohm is there any calculation formula? I have some 300ohm with me. I may use what i have

@W8TJM Жыл бұрын

The length is determined mostly by the velocity factor of the transmission line section, and your 300 ohm might need to be slightly shorter than when using 450 ohm. I hope to work you on the bands Mohamad! The 300 ohm should work fine.

@DXingTV 8 ай бұрын

Thanks Mohammad, I was thinking the same question. I have been unable to get 450ohm Ladder Line, but was able to get some 300ohm as an off cut from my new club. Frank VK4FEM

@JohnMcIntosh-io3fe Жыл бұрын

I would liketo build this in either a 10m or 15m configutation out of some 1/2' dia aluminum tubing radials off an old antenna. How would I connect the pieces of tubing, they are 6' diameter. being able to break itdown for portable use is my goal if possible. Looking for suggestions. Thank you from Ontonagon. Great videos.

@W8TJM Жыл бұрын

Thanks John. You would likely need a short piece of smaller aluminum tubing to go inside, or larger tubing on the outside, and then compress it with hose clamps. The normal way to do it is to use decreasing diameters of tubing (with slits at the end that allow the hose clamps to tighten it) that fit inside the lower section. I suppose you could even use copper tubing if it is only used for short periods. Copper and aluminum together will corrode pretty fast if held together, but fine for short periods.

Ең жақсы KZfaq

Пікірлер