Demonstrating NVIS communication from the bottom of a valley - with U01 Antenna
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- Опубліковано 5 вер 2024
- Demonstration how NVIS works from the bottom of a valley.
Also: Testing David´s new pole holder (DL1DN from QRP Lifestyle)
Contact David (DL1DN) at info(at)dn-performance.de if you want to purchase his Car Pole mount.
I've been hamming since the 1970's, and in nearly a half-century of playing with antennas I came up with the best non-directional antenna system... a quarter-wave vertical and an NVIS wired to a switch. The vertical has the extreme range sometimes needed, but leave much dead space on the way there. The NVIS covers the dead space and serves well for communication on the lower frequency HF bands. The vertical must be properly counterpoised and I'm not talking a couple of ground radials. Think a half-acre of heavy gauge chicken wire .
Thanks for your comment. This would be a good stationary setup at home. Best of both worlds.73 Manuel; DL2MAN
With my work on 2 meters, my Elmer has strongly emphasized getting my antenna above as much of the surrounding topography as possible. You have clearly demonstrated that the basis is different for HF. Thank you for the clear demonstration and the clarity of your presentation. Well taught.
It always depends on what you want to do. Usually an antenna needs a certain height above Ground. In our case, we want steap radiation, not flat.
Fantastic. This experiment replicated my location conditions of terrain. Thank you for the video and explanations!
Nice. My 11 and 14yr daughters are US General licensed. They are learning to use their NanoVNA and tinySA. I got them a 705 recently, and if there is another USA build of the tr uSDX id like to get them to build one each. Great videos!
That was a good demonstration of an essential ecom mode of operation.
Being a native of Florida, I'll have to wait for a vacation to duplicate your success.
However, I have had good success this past summer using 80m phone NVIS to check into the N. and S. Florida ARES nets with 20W consistently. Below 20W I would sometimes need a relay station to check-in.
My antenna was a 135ft 80m-10m EFHW deployed at about 25ft across a tree canopy and over a 5ft tall chainlink fence that seems to be a good reflector.
The EFHW antenna was a so-so performing antenna until I followed suggestions based upon experiments performed by Steve Ellington. He experiments suggest that grounding and choking at the antenna feedpoint provides about 3dBr improvement over other methods, specifically the most popular of grounding and choking at the transiever.
I now feel confident the EFHW is performing within -1dBr to -2dBr to a tuned dipole. With the ease of deployment of a EFHW antenna compared to a dipole the EFHW is now my goto antenna.
ua-cam.com/video/MzfQybYMlUc/v-deo.html
Excellent Video, I used NVIS on St. John, USVI after Hurricane Irma and just after H. Maria, on Bethany Hill above Cruz Bay, the antenna worked wonderful.
Excellent info, Thanks! A subject I've been interested in for many years. NVIS Skywave Medium range HF Comms. Greetings from Canada , Mike. VA7FYT
I can confirm: NVISon 40M just works. My setup for NVIS is a "dipole". Why I write "dipole"? Well, until now it is not a dipole as expected, but my 9m EFRW setup "abused" as a dipole with the 1:9 UNUN about 2M above ground and both 9m wires at the same height. Will build a resonant dipole without the UNUN just to save weight for portable use.
Great video and love the improvement in the audio, the new mic makes all the difference in the world. 73 from Texas KV5P
Thank you Manual. Very proffesional video with super audio. Planning on building my NVIS.
Nice audio to your recording! Thank-you. A pleasure to listen to.
a VHF/UHF radio operator's nightmare in that kind of topography no problem for NVIS on HF !
I spent 31 months in Germany during my enlistment in the army. The terrain is very much like north eastern Pennsylvania where I live. We don’t have cell phone reception here either.
Nice video... Great day in the woods! 73
Das sieht aber hier wirklich nicht so schlecht aus. Dieser Versuch sollte einmal in Lauterbrunnen CH gemacht werden. Oder im Wallis CH. Da wird es erheblich ruhiger. :-)
Pretty location, and excellent audio from the wireless mic. Thank you for getting it. I have often had difficulty with weak audio from your videos, and have sometimes had to wear the headphones and ride the audio gain in order to catch everything.
Excellent demonstration. Congratulations!
Very cool video-thank you. Reminds me of elk camp.
Best looking drive-over support I've ever seen. Nice video.
Yeah, David did a great job and really deserved the money, I paid him for it.
I loved living in Baumholder, Germany for 4 1/2 years (Rheinland Pfalz). For my NVIS I use one from the PRC-104 radio set.
The LiDAR image shows numerous small craters that’s clearly from artillery impacts during the wars. Most likely it’s American artillery since it was rare for us to use air burst rounds which Germany used often and with good effect. Thanks for sharing.
Baumholder is a very nice area. I like the terrain and forests there. The craters on the LIDAR Image are not from artillery, they have something to do with ancient harvesting of stones. In Bronze Age, they collected stones for their grave hills. Up to medival times, they harvested stones to build their homes. This area here is not known for heavy bombing in WW2. As mentioned: Middle of nowhere ;)
My mother's family emigrated from the RheinPfalz many years ago, never was able to get back for visit. That's quite an antenna.
@@dl2man my goodness! I had no idea they harvested stones like that, thank you for telling me, I’ll keep that in mind now. I went to Bastogne and St. Vith Belgium a couple times a year (except when I was in Iraq for 15 months) and the forests where the battles occurred are still peppered with small holes and craters, most of them are foxholes the Infantry dug II hated digging foxholes but thankfully I only dug a couple in my 26 years of service….in the Infantry, lol. I own a couple dual band radios but I’m very nervous about getting on the air, even after I get my license. I don’t want to interfere with professional radio techs like you and embarrass myself. I can easily communicate on the radio for my job in the Army when I coordinate indirect fire, friendly troop movements or close air support. We have strict formats we use for support missions so protocol is critical. So for now I DX with a couple SSB radios to listen in and admire the long distances. I’m also aware of our current Grand Solar Minimum and how it’s affecting various bandwidths. I wonder if you’ve noticed any degradations from the solar minimum while operating? You’re up closer to the polar region where our “shield” generates and I heard the aurora has shifted farther south towards northern Germany, must be beautiful.
I was also posted in Aschaffenburg, Germany for a couple years when I was 19 (1984-1985) and it reminded me of my home State of Oregon so I enjoyed walking through the local forests and I came across HUGE craters that’re slowly filling in by the forest. You have an amazing country and it pains me to see “refugees” and “immigrants” flood into Germany while paying no respect for actual German citizens that need the help more.
One thing to keep in mind is if the Russians and NATO fight each other, you can expect a broad spectrum jamming in certain areas and the wattage those jammers pump out can fry the radio finals unless properly protected. It’s great to meet you.
SFC Kevin M. DeVos
San Antonio, TX
Infantryman. Retired
great info
Super Sache, ich teste damit auch viel herum bei meinen Aktivierungen. Und ich bin erstaunt über die Ergebnisse. Ich hatte bei meinem letzten Aktivierungen nicht mal eine Mast dabei. Ich habe die endfed einfach im Wald in circa 2 m Höhe über die Sträucher und Bäume gelegt.
Mit dem FT 818 / 5w am Ende über 117 QSO mit durchschnittlich ziemlich guten Rapporten… das ganze auf 40 m… 73
Das kann ich nur bestätigen, ich arbeite sehr oft mit 1m tief hängenden Antennen und es funktioniert super, gerade auf 40m
@@QRP.lifestyle absolut ! Und es macht Spaß zu schauen, wie weit man gehen kann und dass es noch funktioniert. Die meisten probieren es gar nicht erst aus. Mein dipole auf der letzten Burg hing nur in 1 m Höhe über dem Boden… auch wieder nur mit 5 W, knapp 90 qso im log und auch wieder geile nvis Stationen die grade mal 30 km entfernt, waren aber durch sehr viele Berge unmöglich über Bodenwelle zu Stande kamen… 😀
@@dd6fm geade gestern noch für den Notfunk Test auf 1m gehangen und mit 2.5W gut durchgekommen auf 40m. Die Leute machen es einfach nicht "weil es ja nicht gut gehen kann:
@@QRP.lifestyle ja ganz genau, weil es halt überall heißt die Antenne muss hoch hängen… wer dann nicht die Möglichkeiten hat, der lässt es ganz. Mir macht das Spaß mit QRP .. es hat einfach seinen Reiz, wenn man sieht, wie gut es doch geht. Und es spart eine Menge Gepäck und Gewicht 😅
Hallo zusammen, ein befreundeter OM aus meinem OV hat bewusst seinen Dipol für 80m in 1m Höhe aufgehängt und getestet. In der Höhe ist das ein nahezu 100iger Steilstrahler, was ihm in den Abendstunden und Nachtstunden völlig überraschende Verbindungen gebracht hat. Und was für 80m geht, geht natürlich auch auf 40m. Ganz klar dabei: So niedrige Antennen werden nicht das DX einfahren. Aber wenn man das gar nicht will, eine top Lösung für nette QSO!
Wenn dann noch ein Bach durch das Tal fließt und der Boden großflächig schon nass ist, ein wahrer Traum...
Gruß Stefan
Excellent video, thanks for putting it together.
Thank you for this demo
Danke! Excelolent information.
Well done! Thank you
Very interesting test.
Thanks
Great job!
Manuel ... fantastic demonstration of NVIS Sir! tnx & 73 - KF6IF
Nice setup, I usually just throw my wire in a tree with a arbalest line and bean bag. I do have a couple fiber glass masts I can setup with guy lines if there aren't any trees. But that's just me, I'm lazy. Subscribed btw, 73 de AI5DD tschuess.
Very nice vid, and very informative! thank you! 73 - KA0NCR
Every one needs a satellite text messager garmin inreach mi . Great video
Yes, the Garmin InReach Mini with via satellite texting is marvelous in a wilderness emergency where you may be so badly injured stringing up an NVIS antenna would be impossible.
Nice video! Thank you for sharing your knowledge. 73 BretC/AC0AE
Looking good .. . 💯👍🙋♂
I wonder if your vehicle aids in signal reflection?
With long distance results to the East is that in line with the antenna? NVIS bouncing upwards with the shallow slope or merely pushing through and up the valley - what was the orientation of the antenna (transformer to mast and also the valley?)
Hi, I explain the setup of the antenna very detailled in the "lidar picture" segment. Transformer was in the west. End in the east. The valley runs roughly west-east. I had no contacts to the east. 2 Contacts further away west, and the remaining contacts were mostly nearby north (where the hill was blocking )
Are those LiDAR identified shell craters from fighting in WW2?
Most likely the craters are signs of ancient "stone harvesting". Do a google picture search for "Jura Kalk" and you´ll see what they "harvested". 73 Manuel; DL2MAN
amazing!!!
What antenna was that ? What balun , what lenght for each resonant band? ZS6AF
It was the U01 Antenna. I have a Playlist on my channel around that Antenna: ua-cam.com/play/PLcV-YqR57ZGNZNwQ8D9BFD8ieTa3aWhc_.html and a Page with all the Details including Gerbers and Print-FIles: dl2man.de/u01-emergency-communications-antenna/ Check it out ;) 73 Manuel, DL2MAN
Great video I find NVIS very interesting I assume the 705 was not full power using the battery so maybe 7 or 8 watts?
The initial QSO (SOTA Sation in France) was with IC705s own Battery (5W) and the following QSOs were with full 10W using external LiFePo4 Battery.
Excellent video! Could you share some information on your obviously 3D printed IC-705 frame/cover? Is this a self developed 3D print or can the print be downloaded somewhere? Any information would be very much appreciated.
73, Johannes - DL1JRM
Hi Johannes, The print files are from thingiverse: www.thingiverse.com/thing:4709792 credits to ON4VH for sharing. 73 Manuel; DL2MAN
Thank you very much for your quick reply, Manuel. Very kind of you!
73, Johannes
Middle of nowhere 🤣
What transceiver is that?
ICOM IC705
I'm interested in nvis. What height was your antenna above the ground?
Hi, I´ve set up a page with all the information about this Antenna: dl2man.de/u01-emergency-communications-antenna/ and there´s a lot more videos to watch, if you´re interested in that antenna: ua-cam.com/play/PLcV-YqR57ZGNZNwQ8D9BFD8ieTa3aWhc_.html
If you are in an area with tall trees like that, do you absolutely need an antenna like that? I have a uv-5r and I can't hear anything from it.
uv-5r is VHF/UHF (much higher frequency) compared to HF, which is what I was doing. Antenna Size is determined by frequency used. I suggest to gather some basic knowledge about radios and frequency. If you would visit a course in preparation for your ham radio license, you learn stuff like that, and I can only encourage you, to do it. Knowledge is power ! 73 Manuel; DL2MAN
@@dl2man The book for my technician license is arriving today. I know I don't know enough right now to point myself in the right direction.
@@coolbeanzs Great move ! We´ve all started somewhere. What I did in my Demonstration was HF or Shortwave. I transmitted in Modulation SSB (opposite to AM/FM, which you might know). Frequency was in the 60m Band (Frequency around 5MHz). This should give you plenty of words to search for on youtube or google. Start with something like ua-cam.com/video/Ow1hxClR5J8/v-deo.html And just to reply to your initial question: Yes, for shortwave or HF, you need bigger Antennas compared to VHF/UHF, what your UV-5R can do. On VHF/UHF your range is basically limited to line of sight, while on HF or shortwave, our signal is reflected off the ionosphere. 73, Manuel; DL2MAN
what is that antenna?
dl2man.de/u01-emergency-communications-antenna/
73
Why not erect V-DP antennas? It would be more efficient.😄😄😄
In englischer Sprache tu ich mir nicht an!
Alles kann, nix muss ! Danke für den Kommentar. Das hilft mir für den UA-cam Algorithmus.
Eine höhere Antenne würde natürlich noch besser funktionieren
Eben nicht. Hier geht es um Steilstrahlung. Dazu brauchen wir niedrige Antennen, weil der Erdboden als Reflektor genutzt wird ;)
@@dl2man Das ist doch Unsinn, so ein geringer Abstand wäre viel zu wenig für einen Reflektor. Das Problem ist jedoch die Absorbtion durch die Bodennähe, die zieht den Antennengewinn in den Keller. Maximale Steilstrahlung auf 60m ist mit einem gestreckten Dipol bei einer Aufbauhöhe von 9m erreicht, einfach mal mit EZNEC simulieren, das Programm ist ja inzwischen kostenlos.
@MrTalaue Das ist kein Unsinn. Das Problem ist, daß wir bei "höher" unterschiedliche Dinge meinen. Wenn Du von höher redest, denke ich in n x Lambda. 9m liegt durchaus in einer möglichen Aufbauhöhe, aber eben als Inverted V. Entwicklungsziel dieser Antenne war eben ein möglichst einfach zu realisierendes Standard-Setup zu finden. Diese Antenne funktioniert super als Steilstrahler. (wie hier aufgebaut als Inverted V mit 7m Mast. Einfach mal simulieren ;) Oder -mach´s wie ich: Probiere es einfach aus. Das macht eh mehr Spaß ;) Dann siehst Du irgendwann auch, daß die unterschiedlichen (echten) Böden mehr ausmachen als 2m mehr oder weniger Aufbauhöhe. Dann stellst Du aber auch fest, daß ein gestreckter Dipol in 9m Höhe ein praktisches Problem darstellt, weil er aufwändiger aufzubauen ist. 73 Manuel; DL2MAN
NVIS communication is not magic. It only does what the law of physics tell. It just seem like magic.
There are no special gizmos needed either. End feeding directly on the trx or ATU is fine. Better still is getting some height
over the ground with a low loss feed line. Not terrible important as the antenna can be set low = short feed line.
Safety reasons advocate nobody getting caught walking into the wire. Even a lower wire works well.
A lower than optimum height lower QRM at the cost of some tx signal strength. Closer towards optimum height increase
your tx but might give you more QRM on your rx.
I feed my field antennas with a ladder line (Hühnerleiter). On 80 mb even a 20 meter (1/4 wave) wire do the job good enough.
To top it it of I only run 5 W. There is no magic involved. NVIS is really perfect for a KISS approach.
(Keep it simple, stupid!)
DL2MAN: I like that you don't try to act "tacticool". I think you delivered the message about NVIS.
de SA3BOW
Thanks for the comment. I agree, there is no magic in NVIS. What I wanted to demonstrate in my Video is simply how it works. And what is better for demonstrating vertical radiation, than preventing the possibility of flat radiation by terrain. I think this is quite a powerful demonstration, when the average joe knows: You need to go to the top of the hill for best radio range..... And I think this demonstration helps to let the NVIS Concept sink in..... At least I hope so. 73 Manuel; DL2MAN
AFIU you've used 10W?
I´ve used 5W for the first QSO to France and 10W for the rest, as far as I remember. 73 Manuel; DL2MAN