One more comment to add to this video: if you use stubby omni antennas, they aren't giving as much coverage behind you as they could, because your head blocks the RF signal. You'll get better coverage with omni antennas that have a long stalk and stick up closer to the top of your head (but they'll be harder to pack).

My dad had taught me this when I was 4 (His dad did radar and radio in ww2 and my dad did many broadcasting transmitters and equipment rf measurements for many different types applications) he passed away a year ago. In lockdowns I cared for him towards the end along with my sister. Anyway, he told me that it better to have a match for the transmitter than the focus, unless I want to go to the moon in a very straight path. I then put gave him some goggles and took him for a few flights around the house and garden ( he was almost bed bound ) he was then facilitated by the miniature cameras vtx systems and once again explained the focus pattern of receiving the best possible results to have the widest possible unless you are going for distance. Thank you jb , I only fly whoops but have really enjoyed your videos and the help that you provide.

@LittleMissRollerCoaster

Жыл бұрын

You gonna always learn something from your Dad! You made me miss my Dad too! Well, at least his legacy lives on through the knowledge and wisdom that you have gained from him! 👍🏼👍🏼👍🏼

I only fly long range & I'm often surprised by how many people aim their patches at the same exact angle. I use 4 high-gain patches all at slightly different angles in case I misjudge my position/aim.

@andrewa837

Жыл бұрын

Unfortunately many lowend goggles only have two antennas. I run omni + a DIY helical 3 turn and usually can turn/angle my head to receive.

@fpvflyriding

Жыл бұрын

@@andrewa837 Yeah I have a hard time knowing where my head is pointing!

@Vousie

Жыл бұрын

@@andrewa837 It's not low end. It's analog. The more expensive analog goggles are nearly as expensive as DJI or Walksnail goggles, but they only have 2 antennas whereas DJI & Walksnail each have four. It's because of how diversity works differently in digital than it does in analog.

Same goes for people that look at the ground with patches on.

@Voyajer.

Жыл бұрын

Yup, that's why I have my patch angled up to compensate

I basically had this happen the other day in a different way, I was flying long range and my pepperbox antenna came loose and swiveled to the side l, I didn't know what was happening at the time but my video went to crap, I was just barely able to fly on the Ragged edge of what the Omni antenna would pick up, almost had to activate GPS rescue but I ended up getting it back without it, it was a close one and a good learning experience, make sure you antennas are snug

Fantastic analogy, Joshua! 😃 Thanks a bunch for the explanation! Stay safe there with your family! 🖖😊

Always appreciate a quick explanation

I love how creative your videos are! ❤

very valuable knowledge! many people buy antennas thoughtlessly for a lot of money, and then they are surprised that they work badly. Because they don't know how these antennas work ;)

Nice job JB! Happy Holidays buddy!

Ayyy I'm early to a Bardwell video.

@nikkifleurackers3866

Жыл бұрын

same

I'm also an electrical engineer. Everything Josh said is perfectly accurate, and it's refreshing to see a KZreadr talk about a rather complex and technical topic without even a tiny amount of error. That's not surprising though, since Josh is an electrical engineer before he is a KZreadr. The principle he is talking about is that the sum of the gain (technically, directivity) has to be equivalent to an omnidirectional antenna. Because an antenna is a reciprocal device, like he mentioned earlier--it works exactly the same in the transmit and receive case, different designs can only change the distribution of where the antenna is most sensitive at, but the total amount of energy it receives is always equal. It's just conservation of energy in different terms.

I totally had a flashback feeling of Bill Nye the Science Guy and I loved it!! Awesome video JB 👏🤟👍

I'm still using the factory antennas for my DJI v2 goggles. Great penetration and great coverage.

Great Demo JB! Always giggle to myself when I see high-gain antenna pilots looking at the ground.... ALSO! I've used the RapidFire OSD in Analog with Patch and Omni to located downed quads... Omni signal osd gives you a distance and patch signal osd gives you a direction to conduct your walk of shame.... Helped me find my quad tons of times!

Knoxville , Tennesse represent!!!!

Love the video, JB!

This is a great update to the video you made several years ago.

Great f-invite explanation love it! Thanks J

Your flashlight example to explain gain was a great explanation, very helpful thanks.

You read my mind...I was really curious about this exact topic a few days ago with those patch antenna on DroneNation.

Great presentation!

Those stubby omnis are useless for flying behind yourself, I use a lollipop long which stands way above my head.

Awesome video. I always figured that was the case but now I know.

Well said

Great video as always. What about doing a deeper dive video on the radiation pattern of different antennas. Most patch and chrosshair style antenna have a squarish beam and the double crosshair or pepperbox style antenna have higher grain but make a wide short rectangular pattern

I love your videos its like vsauce for drones so therapeutic how you break down all this knowledge i appreciate you! (:

you are a genius, a week ago my most trusted quad have lost video and crashed and i couldn't figure out why... it was at the same location i always fly, and it was a 360 flight all around me. the only thing that was changed was the AXII patch antennas i've just installed on my goggles before this flight, when i flew behind myself the quad suddenly lost video and crashed. thanks.

It would be nice if goggle manufacturers added a compass to the headsets that would allow beta flight to talk to the goggles and give a turn your head indicator, you could add the gain and it would draw a box representing your signal.

@bugsy742

Жыл бұрын

That’s actually a really good idea mate 🤝

Thank you jb

Question - Will the HAPPYMODEL 2.4G ExpressLRS ELRS Micro TX Module ES24TX fit in the Frsky X9 lite module bay

Can the dji goggles 2 antennas be upgraded??

Shoulda done this one closer to Halloween lol Thank you for the info!

This is a great comparison and while some understand this there are still many that have no idea and that can have potential for lost craft or accidents if not careful.

Given that all of the digital systems out today use 4 antennas, is there any reason that you couldn’t use four moderate gain directional antennas (say, antennas that have a 90 degree beam where their reception is at least equal to an Omni) and still have full coverage all the way around you by just aiming them at each spot? Or, for DJI and Walksnail, would there be an issue because not all of the antenna connections on the goggles are capable of transmission? (Also, do the systems even function if the goggles can’t transmit a signal to the quad, or do they basically just go into spectator mode? E.g. if you were to put an rf absorbing cap on the transmitting antennas, would the goggles even give you video from the quad?)

i saw a video from whirly bloke on this subject i remember he exlained the antenna gain coverage range as a baloon

What about the difference between 4 stubby Omni’s or 2 stubbies and 2 patches? I need to run my own tests to see what works for me but curious on your thoughts.

Could you use a patch pointing to a different direction? if you have option for 4 antennas you should have a 360 degree cover, Am I wrong?

We need a way to connect multiple patch antennas to one vrx.

Spread the gospel, preacher. The jist of it is there's always a better setup for every flight. Omnis or high gain are tools to get the pre-planned job done.

put a patch antenna on a gimbal and mount it on the quad....infinate range :)

How about a goggle design where there is an Omni and directional behind your head as well?

No pain no gain

i like the josh face in the dark. werent you in the band queen or something?

Slightly off topic but...Gorilla Link has a new set of 900mhz ELRS TXs. If you have Xfire gear, could you compare their performance? 900m ELRS could be a great option in long range with a better product refresh cycle than Xfire but there isn't much info out there. Thanks!!

@JoshuaBardwell

Жыл бұрын

It's just a FrSky R9 module with 2 watt mod. People have been doing it since way back. They just slapped a logo on it.

So if a person attached 4, 90-degree, high gain antennas to his goggles/receiver, pointing 90 degrees from each other (or 6, 60-degree antennas, etc), would he have a 360-degree "high gain" pattern?

A few years ago, VAS had a video where he talked about needing a wider radiation pattern because people tend to do the "Stevie Wonder" while they're flying. The TrueRC X-Air and VAS Crosshair antennas are supposed to have a wider pattern to help with that, so I was definitely surprised when you completely lost video at 90 degrees. But I guess if you were at the edge of omni coverage, that would be expected. Maybe you mentioned turning down the power and I missed it. When I flew VAS stuff, I could fly pretty far behind me through trees and buildings. I only switched to primarily omnis( Singularities) for the form factor when I'm not pushing range.

Like a wide angle lens vs a narrower, you can see further with the narrower. But you can see more with the wide angle.

4:00 Perfect! Knowing what the pattern of the antenna is and matching it to your flying needs is the perfect answer. The flashlight concept does not show what is really going on, the manufactures radiation map explains what the antenna is designed to do. RF is magical, put a LHCP and RHCP high gain patch on your goggles then fly the multi level parking garage.

I think the VRX could display an arrow or something 2D like a radar map to guide the user turning his head.

We already know this because we all have our amateur radio tech licenses 😊

How much of high gain DB should i put in a Omni antenna to get same directional range but in 360 deg.. may be a ratio?

@JoshuaBardwell

Жыл бұрын

High gain omni antennas have a flatter pattern more like a disc than a sphere.

@AfafPrinceOSH

Жыл бұрын

@@JoshuaBardwell so wouldn't it be better if companies use a 1 patch and 1 Omni and puts a mini rssi tracker? It would be more beneficial

@spikester

Жыл бұрын

@@AfafPrinceOSH Antennas in a line-array config would do better horizon. EDIT: of course this needs relevant tx gear equipped with the timing system for directing the energy.

Until I switched to DJI a month ago I was using the immersion RC dual patch on my hdo1s and experienced this all the time.

@Vousie

Жыл бұрын

I initially had my analog goggles with two patches 'cause that's what they came with and I thought that given they're pretty low gain antennas the angle would be wide enough for me (I always fly in front of myself). Turns out they were not, and I found the signal dropped out really easily if I didn't aim my head really accurately - which took too much concentration that I needed for flying. So I bought an omni and swapped it with one of the patches and got much better signal.

@livelyfpv4870

Жыл бұрын

@@Vousie I did find if I went behind myself my range dropped drastically but always had way more range out in front. What I ended up doing is sitting where I was always flying in front of myself. U are right thou having a pagoda antenna does give you more all around range. Although I do still fly my wings on analogue and have no issues. Wings easier to track thou.

Just in case my subversion of algorithm didn't work, what are your thoughts on the "SoloGood 5.8Ghz 2W VTX FPV Transmitter Over 20Km Range TS582000 5.8G 2000MW 8CH Video Transmitter with 5dbi SMA Antenna for FPV Racing Drone Quadcopter" on amazon?

@JoshuaBardwell

Жыл бұрын

I would stick to a known name brand like Foxeer Reaper, Rush Tank Solo, or TBS Unify.

@cwwisk

Жыл бұрын

@@JoshuaBardwell I agree, but 2W sounds too good to be true. Do you think it is? Regardless of the legality, do you think the output could be that high and give a decent enough flight time to make use of the extra power?

Hi! Vsauce, Joshua bardwell here!

One Love

I run 4 omni as 75% of the time I'm in front of myself and 25% behind. how much extra advantage do I get behind myself with 4 omni vs 2. Would I actually benefit from going 2 patch 2 omni. I fly all mostly DJI O2, a little O3.

@JoshuaBardwell

Жыл бұрын

I think you'd benefit from 2 patch 2 omni.

@Jonsbasecamp

Жыл бұрын

I go 3 patch 1 omni with DJI goggles.

@doccock100

Жыл бұрын

@@JoshuaBardwell Thanks dude! will try

Jokes on you Josh I fly from a 360° spinning roll-ey chair 🤪

Sometimes high quality lab-level testing is superfluous in FPV. Real-world experimentation has a lot of value because that's where we fly. I'd much rather see results like this in your yard than just straight data.

You can tell you grew up with out a cell phone. Love how you used the flashlight.

@darrenmay2508

Жыл бұрын

Why, does your phone's flashlight, or rather the illuminated flash bulb have an adjustable focus beam?

I covered this on my channel years ago with animations. You are welcome to use those animations or anything from my channel that you like.

0:41 Hey VSauce, Michael here

Or you go with a bigger antenna to get higher gain. I make my own antennas for ham radio stuff, including 2.4ghz and 5.8ghz. Yet, having a giant antenna mounted to the goggles isn't comfortable. When doing longer range stuff, I tend to go with antennas mounted on a tripod. I love my VNAs and antenna modeling software.

@jgrudnicki

Жыл бұрын

What cable do you use to attach the antenna to the goggles? How much signal do you loose due to the remote installation?

Did everyone forget what directional antenna are or something? I doubt it

That's why I always use omni-directional antennas when I use a head tracker.

What are the Ukrainians using for there drones Joshua ??? What is the max range of the unit Sir ?? Nice video

@JoshuaBardwell

4 ай бұрын

If you're curious, they're taking volunteers. Let me know how it goes.

@victoryfirst2878

4 ай бұрын

Well I will have to pass right now. Can you answer the question asked Sir ??@@JoshuaBardwell

@JoshuaBardwell

4 ай бұрын

My impression is that the Ukrainians are using whatever they can get their hands on. If you don't feel like volunteering, you can donate at: www.dronesforukraine.fund/ As for the max range ... it depends on too many factors to give a single number.

Hear me out.. A 3 axis servo mounted patch antenna that is able to use the signal quality to find which direction to point the patch antenna in so that the patch antenna is always facing in the right direction 😮

@ctvxl

4 ай бұрын

what you are describing exists (sorta) - It is called an antenna tracker, but I don't know of any that can be goggle mounted. They are for ground station setups, and typically use GPS to always point at the craft. A good antenna tracker combined with a very, very high gain dish antenna can go very far even on low wattage. Back in the day, there were guys flying 100+ kilometers on 25mw using a setup like this.

Karen just paid me a visit telling me I have to stop flying my drone because she doesn't like the sound it makes . She also stated its illegal for me to fly at nite and I have to be FAA licensed. I told her she was harrasing me and to leave . I wasn't even flying my FAA licensed 5 inch racing freestyle drone I'd been flying the nite before. The one with the Larson scanner programmable LEDs for flying at nite 🤔😱🤣🤣🤣 I prefer 2 omni 📡 😁

. . . and snow is white . . .

Always thought this was common knowledge. Quick tip, you can use this to find a quad lost in high bushes and you can't hear the beeper. Just pull out the Omni, run only the high gain directional, turn in different directions till you pick the quad signal and go in the direction the signal is increasing in. Works kind of like a beacon.

The flashlight is a perfect example. RF is light and light is RF, just different frequencies. An antenna infact works very much like a light bulb with a reflector.

But this is just common knowledge… The more high-powered patch antenna, the smaller, the beam… Unless you’re using a pepper box lol

Dbm= Absolute Power... Dbi= Directional Power..

Goddammit I literally just bought those antennas lol

For some reason Joshua reminds me of Michael from v sauce

This is actually my specialisme.. and theres nothing "hidden" about it.. Just unknow to many People. So your title is correct" nobody talks about"

@JoshuaBardwell

Жыл бұрын

I think a lot of people either 1) don't know about it at all, or 2) assume everybody knows about it, and so they don't mention it. That's the intent behind the title.

But Joshua, how can we have our cake and eat it too?

Well presented with the flashlight illustrating the downside of a directional antenna. Perhaps it wasn't mentioned recently perhaps, there are definitely other KZreadrs who have talked about this downside and that you can't get this signal gain without giving up on something in return. Like this video by Bruce from NZ: kzread.info/dash/bejne/dKxrya-Op5Szd9o.html where he uses a balloon that he squeezes, to illustrate the changes in where you still get decent signal if using a high gain antenna

@Vousie

Жыл бұрын

Well, there's efficiency as well... So you can have directional antennas that are just not made that well and then get omnis that actually have better range 'cause they have better efficiency (though a case that extreme doesn't really happen much 'cause antennas are generally quite well-made). Then there's cross-polar rejection which also has some effect... All I'm saying is there's a lot more to antennas than just the gain.

I used my patch to fill in my blind spot ( I think it’s my Wi-Fi causing it )

@spikester

Жыл бұрын

You can use the higher channels on DJI I believe to avoid most wifi bands, but of course nearby wifi could always blow out any RF frontends.

@nuffpropsfpv3870

Жыл бұрын

@@spikester don’t use dji but thank you . My dad built transmission equipment for the bbc ( they own the tv broadcast in the uk ) I’m a whoop guy so analog for me still but again thank you

@spikester

Жыл бұрын

@@nuffpropsfpv3870 It does apply to analog, Bardwell & MadsTech both have channel graphs somewhere showing bandplan of which 5.8ghz channels to mostly avoid. A chunk of that ISM band depending on country is lesser used by modern wifi equipment.

@nuffpropsfpv3870

Жыл бұрын

@@spikester thank you 🙏🏻

Liked the flashlight explanation. Relevant from 1947, -> kzread.info/dash/bejne/fHyHsrScgsrTf9o.html if you want basics to start building your own antennas. To be fair, you can really go wild and build a 6 or 8 way patch splitter+amplifier and just have them in every direction at long range, but the goggles would look weird. Maybe too much

2:00 i will see you in my nightmare tonight thanks...

If you use the Wez Varty style of dish plate antennas you better not get a cramp in the neck. :D Check here:kzread.info/dash/bejne/d46I26R9Y6bSlrA.html at 09:57

This is a secret??

I thought anyone who thinks about changing antennas already knows that.

Why does everyone start to whisper or speak in hushed tones when filming in dark or night conditions? Kinda funny

I thought most pilots knew this.

@twinturbostang

Жыл бұрын

So did I. This is not new information. There have been many tests over the years showing the advantages/disadvantages to directional antennas.

@JoshuaBardwell

Жыл бұрын

Always new people coming into the hobby who don't know things. I see a lot of people saying, "why don't you use high-gain patches when you do tests?"

Why are we whispering?

The first company that creates a dynamic gain antenna will win the game. The patents exist (US20030122714A1). We have the tech. Why confine ourselves to a static gain?

You realize that the omni antennas don’t get reception, either when you turn around, right? Try flying without the omni antennas, behind and beside yourself, and I am sure you will see in real life world experience, that even though the physics say one thing, sometimes real life experience has variables that might not be known. I assure you the sideways and rear range and penetration of the 4 cross hairs is more than sufficient than you will ever need, and I bet you don’t gain much if any range beside or behind yourself by using the omnis. So, why not take advantage of the extra distance in front of yourself, if you are not losing any useful range or penetration beside or behind yourself? The way you presented your argument, you made it sound like you can’t fly beside or behind yourself, at all, and that is not the case. Now, if you look at the ground while flying, this all goes out the window. -- and they are not patches. Patches are not as good as crosshairs. X-air -> cross-hair I say this with all the love in the world, buddy. :) no offense intended.

@JoshuaBardwell

Жыл бұрын

I know that the stubby omnis don't give much coverage behind unless you have the extended ones that raise up near the top of your head. I think the argument you're making is that, if you're using stubby antennas, then the omnis aren't really adding anything to the relatively wide beam of the X-Air. I don't think this test supports that though. This test, as imperfect as it is, shows that with stubby omnis on the goggles, I could turn nearly all the way around and still maintain link, whereas with 2x directional antennas, I saw reduced bitrate at about 45 degrees and completely lost link around 90 degrees. In other words (as expected) having directional antennas gives a more focused coverage beam than having omnis. Realistically, it has to work this way. That's just how antenna gain works. The result would be even more pronounced if I had extended omnis that poked up near the top of my head. Your argument is that sideways and rear range of the crosshairs is sufficient. I think I acknowledge in the conclusion of the video that is going to be true for some people and not true for others. I distinctly remember flying analog at an office park with LZR patch antennas and being really frustrated that I had to keep turning to face the quad as I flew circles around myself. My range to the sides and rear was significantly reduced. I ended up switching back to omni+patch. I tried to be careful throughout the video to say, "significantly reduced range to the side or rear." I never said you can't fly to the side or rear, just that you'll get less range in that direction. I stand by that statement.

@LetsFlyRC

Жыл бұрын

@@JoshuaBardwell Crosshairs side/rear range/penetration may be significantly reduced in comparison with “its own” forwards range, yes, but I don’t agree that crosshair (which is different from patch - you keep saying patch) sideways and rear facing range is “significantly” reduced when compared to stubby omnis. I think we would both agree that you don’t plan to use long omni antennas on your goggles. But, even then, I don’t believe you will gain that much of an advantage. I am planning my own video - which is less scientific in approach than yours - to show some real life experience.

@vjaygroup8759

Жыл бұрын

I believe everything tested carefully in realife, not guess blah blah base on spec on website, or advertising of antenna manufacturer. If the test result like this like that then people try to find reason why this result not good. I prefer the one best with tested, the other thats should be better because of its good spec we see on website of manufacturer just leave it for them to prove by testing in real life.

I thought "nobody is talking about" this because everyone already knows this...

Hidden? Whaaaat.. It's like... really basic knowledge you gain by reading one thing about antenna gains.. I thought you'd say that receiver might overheat if you blast 1,6 watts into a satellite dish in close proximity or something, but this...

Didn’t learn anything today, again.

@JoshuaBardwell

Жыл бұрын

Cool! You're very smart! If everyone was as smart as you I could retire.

i thought this is common knowledge

"RF-ily" I just learned a new word today. 🥲👌

@mopar392ta3

3 ай бұрын

Radio frequency I love you😂

Hi @JoshuaBardwell Great Vid Cheers Evel-Knievel

As a long range pilot I can absolutely confirm that high gains give more range, but maaaaan, you BETTER know EXACTLY what the side range of your antennas is. Lol

Please someone donate me a fpv drone ! Budget short here..