Improvised Field Comms - The Jungle Antenna
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- Опубліковано 13 лип 2024
- In this episode, we'll take a look at increasing the performance of your HT with the "Jungle Antenna". It's a field expedient, quarter wave ground plane antenna.
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MATERIAL
* Cobra head - amzn.to/3JxcrAK
* 20 AWG stranded silicone wire - amzn.to/3DZwVhT
* 1/4" Ring Terminals - amzn.to/3Ytv5y7
* S-clip Carabiners - amzn.to/3DZ5Yev
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REFERENCES
* FM 31-20 Special Forces Operational Techniques : amzn.to/3RDdRff
* The Guerrilla's Guide To The Baofeng Radio: amzn.to/3jFOyws
* The Jungle Antenna: brushbeater.org/2015/10/15/th...
* Simple and Fun Antennas: amzn.to/3YbomZn
0:00 Introduction
1:34 HT Radio Test
2:34 First Jungle Antenna Deployment
9:25 First Jungle Antenna Test
12:07 Second Jungle Antenna Deployment
15:28 Third Jungle Antenna Deployment
16:03 After Action Report: Introduction
17:01 After Action Report: Why the Jungle Antenna
18:21 After Action Report: My Jungle Antenna Design
21:39 After Action Report:: Member Suggestions
22:49 After Action Report: The Antenna Build
29:07 Close
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#thetechprepper #hamradio #militaryradio #antenna
Moral of the story is the box it came in is a great place to keep the rubber duckie permanently
People don't realize, but the AAR is the best part for learning lol.
I agree, but the AAR was close to 20 minutes in length . Try being on the editing side of this. ;-) Personally, I learned a lot. Thank you for your contribution to the second half of the video. I need to work on the capture station (SDR) to gather better metrics...I just ran out of time.
@The Tech Prepper bro, 1. You just made a mental connection from one platform to another, kudos. 2. "When your plate gets full, sir, start eating lol" -advice from an old salty first sergeant when I was elbow deep in a task lol. 3. You are doing well at a break neck pace, us subs got you!? 4. Even doing AARs in the Army, dudes fall asleep 😴 and it's often an exercise in wagging the dog. Lol
@The Tech Prepper you got this! You are doing big things!
Nice video. A couple notes: 1. Any wire that has a jacket of it has a V-factor. It detunes the antenna. Makes it lower in freq. The 210 takes up the difference. and 2. the fold over even though it is folded at the 17.x" point, that extra wire is still included in the length unless you short it back on to the main wire. Cal from DX Commander talks about it in his videos. Again, nice video. Great idea on the 1/4 wave ground plane antenna. 👍
I really appreciate this insight, John. You win the "best comment of the day" award. This make sense. Thanks for being a digital Elmer!
Judging from the terrain stated in your video, I think you would have had better or a greater distance with a 5/8 wave for 2 meters…
SH 21-76 and FM 21-76 (Army Publications) explains this antenna. We also called it a Jungle 292. (Two niner two). Between the positive vertical radial and the 3 ground radials it looks like our Army 292 antenna.
Interesting video, 35 years ago we used the same antenna with a PRC-77 radio.
A much simpler antenna was the AT-984a long wire antenna..
The PRC-77 tuned 30-76.95 mhz freq.
The long wire must be 5 wave lengths long.. At 30 mhz the antenna must be 150'.
Higher freqs, works equally well with the 150' length. The key is the horizontal long wire must be one meter from the ground.
Super quick set up. Unreel the 984, point it in the direct of the distant radio set. Put the fork lug under the prc-77, 10 ft whip base scew down the AB-591 base. Again one meter off the ground with the long wire.
No AT-984a. Substitute 150' WD-1/tt commo wire.
GREAT JOB! I followed your VERY CLEAR instructions, and I built a VHF, 2m, 1/4 wave, ground plane "jungle antenna" using a 3-foot piece of bamboo, 14 AWG-stranded wire and all the other recommended parts. It works great with a SWR of 1.2. Mahalo Nui (thank you very much). WH6GTC.🤙🤙
Nice work. These are great performers. It's an added bonus that they're easy to build and repair in the field.
What was the distance of your longest contact or how many miles?
@@digitaldreamer5481 With this setup about 32 miles on simplex. I was pushing 50-80 watts and I have about 1000' elevation advantage over the other station.
Former army radio guy just getting into ham. Love you channel. Love to try and make contact with you from here in Oklahoma.
OK here learning the same. send me your info if you want to try some field tests some day
@medicjbh any updates?
This is a great skill for any Ham to be able to construct a make shift antenna for any band. The flash cards are an awesome idea to prompt you also.
I 100% agree. Making your own antennas is a game changer.
After watching the member video, I mocked one of these up quickly, and have an option. If you switch from 20 gauge wire to 14 gauge, you don't need the spreader(s). It is stout enough to keep a 45* angle without any support, and makes a stronger hanger/radiator as well. S-clips can be eliminated too. A bit more field expedient
I use an Abbree 42 inch antenna up a tree with a 20 foot SMA cable to my UV5R, hooked to a Baofeng mic for more gain, a 19 inch counterpoise wire hooked to the UV5R back screw, and custom squelch via CHIRP software for max sensitivity. Still experimenting with what little I have, but so far this works excellent.
Great series! I haven't built one of these style antennas in probably 30 years! Now I want to again! Thank you Sir!
You didn't mess that video up at all! We all have our low trees !
Our trees are lower than most. In the end, this video was a success. There were lots of valuable lessons learned. I'm happy with the final design that came out of this exercise. Have a great weekend!
My winter field day dipole was only 15' high inverted Vee. I put a video up...see what you think of my WFD. Success for me for sure especially compared to not being on HF much the last 2 years. 🙂 Have a great weekend too!
Love this video , amazing job
Cool project. I am going to give it a try. Thanks for the accurate information.
Excellent building from your first field expedient antenna. Job well done. Looking forward to more.
Thanks. The design was dead simple. It was a happy bonus that I was able to tweak the design for my environment and operating requirements. More on the way.
@@TheTechPrepper I’ve built a jungle antenna with 3 radials but didn’t think about just 2 legs instead of 3. It’s good to know that works and less work.
By using the same cobra head, I built another simple receive only antenna called a LOG or Loop On the Ground. Just a 60’ length of wire made into a 15’ square. It’s receive only but pulls in some clear reception on radios that can tune into SW stations.
@@Rowsey63 Thank you for mentioning your experience with a RX-only antenna. That has been on my list for awhile. Cheers!
You really do honest evaluations. I am Impressed.
Thank you. I'm a fan of experimenting. Some are winners, and some fall on their face.
Great video man! Appreciate the effort to capture every aspect and the after action breakdown!
Glad you enjoyed it!
1000% a proper crimper and crimps make all the difference. I like the one that have a little adhesive in them too. Here's my trick for using smaller gauge wiring in terminals too big, strip double or triple the length length, fold accordingly and then crimp.
I'll try that next time. The right tools make all the difference.
Well done putting theory into practice Gaston, great results yet again.👍
I'm gonna have to start measuring up body parts now.🤓👍
Happy measuring! It's great seeing how the theory stacks up against the real-world. I am a "two radial with one stick" guy coming out of this exercise
Adjustable Trekking Poles, I have the Black Diamond Alpine Carbon Cork 130-100cm when separated gives you three light weight pieces to work with, instead of tree branches. They have measurement markings on them and you could add more for more detailed lengths. I am a ultralight camper and I think a little bit of research within that community you could really benefit from weight savings and improvising the trekking pole sections with a little electrical tape. Just a thought, hope this helps. Thanks for your work on all this!
Great video. I'm happy to hear that you are getting your GMRS licence and will be making this antenna for those frequencies. I'm attempting to assemble a manpack radio using a GMRS radio for my own use. I'm sure your video will be a big help. Thank you. Jeffrey C.
Good work, great video Gaston! Thanks!
Thanks, Brian. I'm happy with the final build. It will be interesting to compare it to my new Ed Fong roll-up J-Pole. Cheers, bud.
Thank you
I built a similar antenna from an old CQ Magazine article. The article I read was called "The Ugly Ground Plane". I built it for 2 meters, and it worked! It was a design similar to what you built. Knowing how to do this in an emergency and having the equipment on hand could save a life someday.
That's great. Based on my experience, I am not surprised that you had good success. Do you recall what year and month the article was published in CQ Magazine?
@@TheTechPrepper I scanned a copy into my computer. I just looked it up. It was in the November 2011 issue of CQ. If you can find it, I think you will like it.
@@davidsradioroom9678 Perfect. Thanks for digging up the year and issue.
@@TheTechPrepper I sent you the wrong link. I did find the Ugly Ground Plane Antenna article, but I couldn't find the issue and page number. I will try to email you the PDF file. I kept it, and I think you will like it.
@@davidsradioroom9678 Received. Thank you for sending it my way. I am going to build one for 70cm and GMRS.
Great video as always.
Did the cobra head connector experiment to create a 6m dipole for my HT that works on 6m. It set off the emergency lights in the building. Lol. But at least I won't have to buy a 6m ht antenna since it hits the repeater well and the reports say it's not full clear, but very readable.
As far as wire, one of the ways I get a lot of wire is looking out for people throwing out vacuum cleaners and floor scrubbers. They're usually 20ft in length, and in most cases you get two wires. The issue however is that you may need to test them since they maybe broken (hence them.throwing it out) and if you need a longer wire, splicing (or soldering if that's your thing) will be needed.
I have a vacuum that just died. Great timing! It's time to strip that bad boy of its wires.
Really good stuff mate many thanks.
Glad you enjoyed it. Cheers!
yes the wirefy stuff is great stuff. They make a bunch of stuff and they work very well.
For a lightweight support system, try using some fiberglass flex rods for the radials. Powerwerx also a terminals that have heat shrink material. Picked some up at a ham fest last year or the year before, can't remember, but they work great.
Great stuff Gaston. 2 radials with a stick to me meets the KISS requirement and fast at the same time.
Yes, KISS for the win. This also allows me to still have a shelter!
@@TheTechPrepper Shelter is good.
I found the same with the "standard" calculation when I built by 6m jungle antenna. It was originally resonant around 46 MHz. I had to shorten it considerably to be resonant at around 52 MHz.
Man, this was 👍 👍 great. Thanks G.
Glad you enjoyed it
I love this kind of tests. 73
Great video as always! I am gathering the parts to make one of these to take for Parks on the Air and emergency communications. 73
Have fun! There are so many possibilities with these simple components.
bit history here: I'm not a HAM but my experience is when I was LURP in Vietnam I had one of those antennas made from telephone wire in my jungler kit in case we could not make commo with the regular antenna. Lots of memory there.
Thanks for sharing your background. Do you recall roughly how high (on average) you deployed your jungle antennas? Thank you for you serving our great country. Take care.
If you work out the base area of the groundplane you could use thin PVC pipe and attach it with that. As long as it is rigid enough to keep them at a 45 degree then it will be a good setup. Also a holder for the wires as well during transport.
Loved this one! I just keep wondering how you might use those trekking poles to help raise/manage that antenna...
Great video. I was looking to buy an antenna for field deployment but I will build one now. The reason using 234 to calculate the 1/4 wave length is to long is that number is for bare wire. With insulated wire you need to consider the velocity factor.
Yep. I found out that the insulated wire is introducing capacitive loading when folded over on the ends. Thanks!
The first dipole i made; the 468/Mhz, gave me readings that the elements were too long. I eventually realized that the space between the banana posts (.75 inch) was something that needs to be taken into consideration (ie the two 19 inch wires plus the .75 inch= longer than the frequency desired).
Materials also are a factor that prevent the universal formula from being perfect and thus why you should always cut long and snip your way to your goal.
Cut long and snip short...that should be a t-shirt.
There are two versions of the jungle antenna that have semi-self supporting ground radials. One uses bicycle cables. Guitar strings/paino wire would be smaller. The other version requires slipping soda straws over the ground plane elements. You would need to McGyver something at your cobra head to support the radial from cobra head outward. Perhaps bottom of water bottle over the vertical element with radials through sides of bottle.
Another measuring tool is your cards. Print a ruler grid on the edges of each card, inches on top, mm on bottom, then you can put your cards end to end to make a ruler.
I’d skip adding numbers so any card in any order will work. 1/4” marks would probably be detailed enough for any field work.
I will be formatting and printing my cards as 3x5”, so that in itself gives you 2 known dimensions.
This is an excellent tip. I think I'll add ruler to the edge. Thank you.
I love your videos and I am a subscriber! I wanted to add that I think, but I am not sure, that the wire you wrap around at the end does add to the electrical length of your wire assuming you use insulated wire. I think when you fold insulated wire back on itself the true electrical length is somewhere between the length of the total wire used and the strait portion of the wire. It is somewhat complicated but it is sort of like a folded dipole. However, if you use lengths that are checked with an SWR meter you are good to go. This might be why your antenna seemed to work well but seemed to be a bit too short with the 234 formula. I am a bit unsure of myself with this though. Robert K5TPC
Thanks for the support, Camille! This makes perfect sense. This is where the DOPE card with the precalculated lengths pays dividends as I won't always have an antenna analyzer. Cheers!
Two or one ground plane radial may introduce some directionality. Normally that is not a desireable characteristic of a vertical ground plane antenna. However, directionality may be an advantage in some situations as +1dBr to +2dBr may be a make or break difference.
The 2 ground radial design might actually offer better directionality depending on orientation. Conversely, it could affect lower radiation on the "null" sides. Nothing like a Yagi, but it might be a benefit in some circumstances. Great work as always. KC8OWL
Good information, will give these a try. Also, next time you get to Ikea (or any store) pick up one of those paper tape measures that are hanging around the store for you field kits.
Great idea. Putting a layer of scotch tape on both sides would weatherproof it, too. IKEA is about 90 miles from us. I'll be sure to grab a stack when we hit the city.
You might want to consider using a stud hook terminal instead of the ring terminals to attach wire radials and dipole elements to your dipole adapter with the captive binding nuts.
That’s sufficient enough for emergency use. Barely readable is still readable to get help if needed.
Your test worked out very well. Not to throw shade, but unless I need an ultra compact kit (and there may be times), I just carry a 2M/70cm roll up J Pole as my primary field antenna. Three reasons. #1 Speed of deployment. #2 The ability to get the antenna up without building something if I am injured. Last, in some areas, there are only 70cm repeaters or you may have both and once again, it saves time if you can not get into a 2M repeater, but can access a 70cm repeater. There would be no need for second set of wire radials with the J Pole. Yes, you can shorten your 2M radials, but again, more time. With the J Pole, I'm not worried about having the correct length of wire. To me in most instances, it just does not make sense for VHF/UHF. Having a kit like you have made does follow the two is one, one is none principal, so yes there may be a need. Now a similar kit for HF to improvise an antenna with whatever you find as to wire in the field (or what you carry with you) also makes a lot of sense and this kit with a couple other items fits the bill for that also. This is why I said, I'm not trying to throw shade. These small kits can be of great value. I'm betting you already have a improvised HF video kit in the works. Thanks Gaston.
I am happy to have any counterpoint. I actually have been carrying a J-Pole for a couple years now. It's the N9TAX Slim Jim that was used on the receiving station. However, I just acquired a much lighter and more compact Ed Fong that will be replacing the N9TAX in my pack. It will be fun to benchmark it against the 1/4 wave ground plane that I built. My only issue with the roll-up j-pole is that it is not quite as easy to build or repair with scavenged parts. Either way, both are now a permanent part of my portable gear.
I’m looking forward to a comparison to the Ed Fong J-pole. My guess is the J-pole will have an additional 1+ dB of gain over this design, but as you stated the jungle antenna is much more flexible in an austere environment.
Dont apologize for the quality the info is what counts. I learned a bunch and my bank account hates you....😉 that was very enlightening for me. Thanks
You're right. I'm done apologizing. Running two cameras was a pain. They were 400m apart, so I was running between two radio camps.
I am curious though. I am a newbie as well. Why would the length of your wire needing to be exact matter in a field enviorment for a spefic frequency? The rubber ducky antennas cover a wide range of vhf and uhf but are short?
@@79attaboy For the best performance, you want your antenna to have a good match with your transceiver (50 ohms) with the lowest SWR. This is done by tuning (trimming) the antenna to the frequency where it is resonant. When you have a good match, the antenna will have less reflected power coming back the radio making it more efficient. Broadband antennas like the rubber ducks don't do this very well, therefore there performance suffers.
Ahhh.. gotcha. That makes sense😉
One idea I had to improve a jungle antenna was to tie some cordage to the corners of the sticks, tie off above the radiating end and hang the hot end from the knot at the top. This was you aren't using the antenna itself as the support to hang from. I haven't tried it, just an idea.
Interesting... A member on BMAC suggested attaching a length of cordage to the hole on the Cobra head and running it vertically with the radiating element to add strain relief.
Good experiment GMan. My experience with the ground plain was about the same. Improvement, but not significant. The roll-up J Pole crushes it. Having the skills to build the ground plain from scraps in the field is important. Good excercise! 👍
Thanks, Dick. I just acquired the Ed Fong roll-up J-Pole. It's very compact compared to my Slim Jim from N9TAX. I also found that the coax that comes with the Ed Fong eliminates the need for the BNC coupler. It has a male BNC on one end and a female on the other. The kit is still improving.
@TheTechPrepper GMan, antennas are fun to play with. Understanding the basics opens up a lot of field expedient Gerryrigging that is very functional. Your video on the terminated dipole and the military manual you referred to have sent me down a rabbit hole. The manual shows a doublet with a twisted pair feed line converted to a terminated sloping V directional antenna. I am now experimenting down that trail. First testing on the doublet with twisted pair feed line is a success. Now some better weather for more extensive testing will be nice. Your creative approach to problem solving is infectious! 73 OM
@@owlcricker-k7ulm Glad to hear that you're infected. The twisted pair is very intriguing as it eliminates the need for the coax and can be improvised in the field. That is on my list, too. If you find any good resources, please let me know. By the way, I experimented with a 6m Jungle Antenna last night. I actually used 3 radials and went back to my guy system since the elements are around 47". I am trying to hit our closest 6m repeater...it's 40+ miles. No luck yet.
It occurred to me that a right angle adapter added to the cobra head would eliminate the curve in your coaxial cable. It won't make any difference in performance and is another piece of gear, but it will reduce the strain on the coax connector.
I'm very curious how this or other variations of the jungle antenna compart to a 1/4 wave whip with a counterpoise. I'll have to do some testing.
If you use almost the same components, but make a 2m Delta Loop, it's quicker to assemble and very easy to make a triangle shape frame with 2 sticks. It performs great!
Great suggestion! I'll try it.
I’d like to see how a quality 1/4 wave whip antenna compares to the improvised antenna and the stock one
Havin 2 radials makes it slightly directional but that mich of a short distance the repeater must be deaf but the flowerpot antenna i said about in another video is the antenna ya want being a vertical dipole
You know under the cover of darkness, you're going to have to replace all the short trees in your AO with taller trees. Lol. Sorry. No need to call Tech Prepper security, I'll see myself out. Thanks for your hard work and sharing your thoughts, tips and ideas with us. KC3UEE.
Yeah, I know. ;-)
Thank You for the information. The last time I was out in the woods I didn't have ring terminals, or most of the things that you used. I understand that we need to have some of the things with us all the time. But can you make an antenna with just a length of coax?
Yes, you can. We'll do that with this series.
To take strain off the top element you could hang off the cobra head then at the right height throw a alpine butterfly knot in your line to hold the element straight, then the weight will be hanging off the cobra head.
Also saw your Instagram post about making one for 6m. Interested in that since I have a 6m capable mobile I need a portable antenna for.
Great info! Keep it up, 73
Or a small prusic loop instead of an alpine butterfly to be able to tension the element once it's clipped on
Great tip, Ryan! I like this design.
I wonder how well a vertical dipole would work. Thanks for the video
Good question!
Hey Gaston, Nice presentation. Only problem: you had a severe shortage of jungle to be testing a jungle antenna ;-)) What might be interesting is to compare the performance under identical conditions the field-expedient (i.e., "jungle") 1/4-wave and an Ed Fong "roll-up" antenna (which is a 1/2-wave j-pole). I suggest that as I think your intent is to test/experiment with lightweight portable antennas for deployment in austere field conditions. BTW: I think that probably the nearest jungle to you might be the north coastal redwoods in NorCal ...
I actually just received an Ed Fong in the mail from Ham Radio 2.0. I like the small size and lightweight nature of the roll-up J-Pole. After getting the Ed Fong, I am going to stop carrying my heavier and larger Slim Jim from N9TAX. The performance will likely be better than the 1/4 wave ground plan. The only issue is that I can't repair the J-Pole in the field or build it as easily. With the Jungle Antenna, I can pretty much find wire anywhere. Everything is a trade-off. I think you might be right, there are no jungles for several hundred miles.
Gaston absolutely a LOT to be said to be able to jury rig an antenna if a primary fails if/when operation in austere environments. Just ask the guys who were deployed outside San Juan Puerto Rico post Hurricane Maria.
Best regards!
@@jimpiper5297 Thanks, Jim. I can't recall if you're a member/supporter, but given your comments...check out the first half of next weekend's video. I had to think on my toes. This was not planned! ua-cam.com/video/3GhvXCQwIAo/v-deo.html
@@TheTechPrepper Look for supporter $ coming your way.
@@jimpiper5297 Thanks, Jim! Every bit helps.
Nice exercise. For a comparison in addition to the rubber duck I would be curious how your role up j-pole antenna performs compared to your home made antenna at the same height. Thx for the video!
As it happens, an Ed Fong roll-up J-Pole just arrived. I plan to try it again from that first location. I'll do a UA-cam short for that one.
Next, try ditching the cobra head. You can fashion a 1/4 (or even 5/8 wave) ground plane using only coax. Just strip 19.5 inches of center conductor and unbraid the braid. Lightly twist the braid into 2 (or 3) radials and POOF!
Secondly, the rule of thumb is to take off about 5% length for insulated wire.
Thank you for touching on this. That's ultimately the plan. This first pass is the "crawl" phase, I plan to jump into the "sprint" phase with your approach.
Gran trabajo... en lo personal... sigo prefiriendo la Flower Pot sin los caños exteriores, mayor ancho de banda y super liviana.. subiendola con un hilo de pescar y un gancho...
Saludos desde Argentina LW5DKN
Cheers from the US! I need to try the Flower Pot antenna.
I think you probably could have gotten very similar results with just an improved / better rubber duck antenna. It would have been nice to see a comparison of your field antenna to something like a Signal Stick which I use and have great success with.
Is a signal stick tri band?
I’m new to this, but my understanding is that having only 2 radials will make it slightly directional. It might be interesting to test it at 2 different 90 degree orientations to the repeater to see if it makes a difference in your signal.
In your application, directionality isn’t necessarily a disadvantage (could even be advantageous), but as a base station antenna in a FOB location, for instance, it could be a problem.
Thanks for jumping into the comments. The distant station was broadside to the antenna, so it may not have mattered. Without modeling it, it is hard to tell. I am still experimenting with 2 vs 3 radial designs.
Very fantastic, Gaston. I enjoyed the Full Lenght of the Documentary Video. I am wondering if I could built myself a Jungle Antenna for 40-10m Band in the same Design like you built yours for 2m and 430Mhz Frequency. Gosh...you gave me some good Input to try out something New. Tnx so much. Happy Saturday Evening & 73 de YFUG 💯🙋♂
Sorry...I know it was a bit long. I actually edited it down from the three hours of captured video. Happy experimenting.
@@TheTechPrepper Nah I wouldn't say that. You are really working hard on your Projects to make them work out fine. And the Thing is you can never explain or document Details just short and quick all the Time to make them understood for everybody.
Just to be honest Gaston, I could not do all this just as half as good as you do. That's why I keep saying" keep up your fantastic Work and never get tired of doing the Things you love to do." It's all for the Love of HAM Radio.
So now it's on me to find the right Day to bring my wrinkly old America down to the Work Corner of my Basement to cut some Wires to Size and with some Abra Cadabra Hocus Pocus and tons of Luck I might be able to play with a New Antenna soon.
73
Great test! I prefer that antenna over a Jpole as can easily be reproduced without test gear if you know the measurements. I've found three radials become more necessary on VHF Low , 6 meters / 10 meters. Yes, you are seeing knife edge diffraction and maybe a little multipath. Initially I thought the repeater receive was terrible, but when I saw the obstructions it made sense.
Last, If you use the traditional 468/146MHz (Frequency in MHz) and divide by two you get 19.2 inches. Multiply by 90% and you will end up at 17.3 inches. Pretty close to your results. The ring terminals or knots at the end of the wire add a sort of capacitive hat that shortens the antenna 5-7% plus 2-3% for insulated wire. At HF frequencies this stuff doesn't matter as much. At VHF and up it does.
Great videos! it is awesome to see someone out there practicing this stuff in the field! Keep up the good work!
Thanks for the confirmation on the Knife Edge Diffraction. I actually built four (4) elements for 6m FM last night to try out. We'll see how that works. The closest repeater is 41 miles. I always carry a roll-up J-Pole, but this antenna appeals to me as I can easily build or repair it with readily available materials. The J-Pole is not easily field repairable or constructable in the field.
@@TheTechPrepper If you haven't messed with 6 meters much you will like it. I'm in the Appalachian mountains and have found that 10-20 watts of 6 Meter FM simplex will make contacts through the rugged terrain where 50 watts of 2 Meters will not even break squelch. SSB is even better. All the old forestry and part service guys lament the transition to VHF and 800MHz for their radio systems. "the old lowband systems just worked better"
@@sixstringforge I figured that 6m would be a great for a bit more range on low power. Thanks.
That’s great Runner! I’m curious if I set the 1/4 wave beside my sheet-metal-sided travel trailer if it will tend to direct the radiation away from the trailer. I may have to do that experimentation myself, but it would be well served. 73s Tom KC3QAC
Please give that a try and report back. I'm on QRZ. 73 de KT7RUN.
I have seen this type of antenna built with hard wire on a table top for 70cm. it was tiny. Honestly 17 miles with any ht is pretty frigging good,. You wont get that range in my neck of the woods ever. Too many hills, trees and homes. you are lucky to get 25 miles with 50 watts in a mobile.
great video however 1 thing to note most of the military setups you would use typically function off of a mobile radio not a hand held, most hand helds i find need a LOS of 1 km or less whether it be a mobile or 40+ foot in the air antenna off a repeater..
Thanks. This is a good point. I plan to test this with my manpacks this weekend.
Great thing about handhelds is that it can push up to 5 watts depending on the unit, which is double the output of a PRC-77 UHF radio (mobile/manpack) which amazingly only put out 1.5 to 2 watts.
Cool. Beautiful desert area. But when working on 6 meter 2 and 70cm why not try a delta loop. Loop might be a tad large but really cool man pack..
Meant to say 6 meter might be too large
If you tattoo all of the formulas on your body, you can leave the dope cards behind 😊
I've been thinking about another tattoo.
1/4 wave jungle with 3 ground planes at least 30' in a tree will reach 5miles just fine with 5watts
Before I watch the after action report, I think the 2 or 3 radials are not needed. Your essentially making a dipole, so only 1 radil would be required. Now adding the other radials may improve things a bit, I think the improvement/slash effort pain ,of use in the field would be not worth it. This is based on some experimentation I have done also. WIll be interesting to see results.
you should hang the rubber ducky in the tree and see what happens. then try it with the radials. itd be nice to see if that works. also how about trying a 5/8 wave version?
Those are all valid option to try. Go and experiment and report back!
@@TheTechPrepper I already know it works. Im trying to give my favorite hamtuber content ideas.
You need to get with an 18E. I'll see if mine has any releasable material that's more up to date..
I'd like that. My email is on my channel page under the "About" section. You guys have all the cool toys. Thanks for your service.
Jungle… Palo Verde? Hay orejas de coneja desierta. Sonoran signal snagger? Dusty dx dangler?
Is there some inherit advantage to using that female to female adapter rather than just using a female cobra head directly???
Not having the Cobra heads in hand, just looking at the pictures, isn't there a couple of structural holes in the body of the cobra head? could you use some cordage thru one of those to both hold the radiating element and then use the cordage to support the entire weight of the setup???
I use the same Cobra head directly with my HT as well. With this approach, I can use it for both the HT and jungle antenna. Check out the first video in the series.
@@TheTechPrepper I have been kinda binging on several of your great videos, I'm still waiting to test for my general, but all things HF intrigue me more all the time. 73
It's a pretty interesting video and counterpoises certainly work but don't discount the effect of straight elevation gain. Somewhere there is a formula that covers antenna gain vs just elevation increase for vhf. With a relocation cable and a line on your rubber duck, you may still have reached that repeater after you raised it 12 feet.
Thanks for sharing. That's an experiment to try.
@@TheTechPrepper Keep up the good work. Experimentation is a large part of what being a ham is about imho.
I'm kind of surprised you didn't just cut a stick to length to put between the 2 radials.
Keep watching...did that.
Height = is Might. Perhaps a light weight, telescopic pole carried, atach the antenna you just made or the N9TAX antenna to the pole , 15' to 20' tall, perhaps pole is leaned against a tree or cactus for support, no need for guying.
Why not use the trekking pole?
It will likely de-tune the antenna as it's aluminum. I wanted something non conductive.
Could the antenna handle 25 watts?
Yes, it handles 25 watts perfectly fine.
What antenna analyzer is that?
It's a NanoVNA. I think I payed sub $50 USD several years baxk. I prefer the RigExpert, but they get pricey once you get into the VHF and UHF bands.
@@TheTechPrepper ah ok, thanks! I will look into that. Great work on the videos.
Wasn't the Antenna about 2.5 inches too short out of curiosity ?
Nope. I was resonant on the frequency that I wanted to work and I had a good match (around 48 ohms).
Yessir. They can be built using many many cheap items.
To me a good local hardware store is also an antenna super store.
Have fun sir. You may need the skills one day.
Yep. The only issue is finding the Cobra heads at the hardware store.
Great stuff. Quick, Trademark "The Desert Antenna". Cheers 73 JQ7BJB
That's an idea! I am happy that I tried three deployment options and found what works for me. The two radial system with the single twig is the perfect balance out here of: performance and ease of deployment with minimal components.
Also solves the problem of guylines being 15-17 feet long with the antenna deployed higher! Good fix.
@@the_mad_swimbaiter455 Yep. I wanted to mention that. I completely forgot. Plus, it allows me to still build my shelter.
If you put a splash of color on the card and use a similarly colored bead on the wire, you won't need to measure in the field.
That's a great tip. Thanks for the suggestion!
I came across a 6m/2m skeleton dipole antenna made from ladder/window line in this video from KM6JUR . There is a picture shown in the video of the dimensions of the antenna. I paused the video and took a screen shot of the image in the video and printed it out.
ua-cam.com/video/XLt9bp8W0Dc/v-deo.html
Since it is a center fed dipole, it can be setup horizontally polarized or vertically polarized.
I made one and according to my antenna analyzer it also shows a low SWR on 70cm.
I haven't used it very much to know how well it works yet, but it can roll up and may be a good portable option for a multi-band antenna for 6m and 2m, and perhaps even 70cm.
sell them!
I'm finishing a commercial dipole design for HF with another ham. I'm considering making a commercial version of this antenna next with slightly different materials. Thanks.