What is SWR (in layman's terms)
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- เผยแพร่เมื่อ 10 ส.ค. 2015
- In this video I explain What SWR means and how it works. Of course my hose and rope demo are similar to what you would see in a 5th grade science experiment, but it really shows how it works quite well and you can try this at home.
- วิทยาศาสตร์และเทคโนโลยี
THIS is a great example of what TH-cam instructional videos should be. Smart guy, no hoopla, to the point, great explanation that resonates (pun intended) with all audiences. I’m new to ham; this totally cleared up SWR for me. Thank you!!
This is, hands down, the best actual layman's explanation of SWR currently on TH-cam (That I am aware of). Very well done.
This is the best explanation SWR on TH-cam. Hands down !
Thank you for that demonstration with the rope. That was very helpful to understand what radio waves look like. Thank you.
That was a really smart and simple visual demonstration for simplifying these lessons! Well done!
Alex, I've got a degree in e.engineering, and must say your tutorial is the best I've ever seen.
Hands down the best and most well described explanation I’ve come across so far. Thanks!
Wow... Thx for that explanation:)
I am 15 years old and from Germany and understand it really good;)
This video was fantastic. I want my 8 year old to watch this.
Amazing video. I'm studying for my ham radio license and got stuck on SWR. This video clears it all up for me. Thanks for this.
I've had my HAM technician license for 6 years and never understood VSWR. Thanks for putting it in simple terms!
Awesome! Went fom murky grey kinda get it, to flat out "gotcha!" concerning VSWR and it's place in antenna specs. Thank you very much for taking the time to make and post informative videos.
Great tutorial.
You were able to simplify this concept by comparing it to things that we already know. Good job !
oh man how long have I been here? I must have fallen asleep? Seriously thanks good stuff some of your vids helped me pass my ham test.
Good stuff Alex. Part of the problem when we go out and do the "right thing" and get a FCC license, is that we are usually only memorizing test questions. I found myself wanting to understand WHY this or that answer was correct. These kinds of tutorials are great.
This is such a great explanation. Well done.
Great. Best explanation on the intertubes. Now if I could just get my indoor antenna situation sorted
This is what I've been trying to tell everyone. Good video well put. Thanks
Great explanation.
I’ve had very talented and knowledgeable engineers try and explain this to me only to further confuse me. You on the other hand can be excellent at teaching to laymen .
Excellent explanation. Very simple to follow.
Confession time, I was all geared up to make disparaging comments, however your video seriously surprised me. All in all a down to earth and HONEST explanation that just about covers what people need to know.
Thank you! Admittedly it took me a long time to figure out how to explain it in layman's terms.
Video Aerial Systems , yes, there are many "teachers" who seek to impress the audience more than they want to pass on knowledge. I did smile at the rope between the RV and the tree. (What ever could go wrong now?"
Awesome video man. Great info
Great video with awesome information! I probably watched your dog for about a minute and a half and need review now =)
Thank you for an explanation that makes sense the first time. :-)
I wish there was a these kinds of easy to understand videos for all RF related terms, since RF can't be seen, heard or tasted without an oscilloscope.
YES! ANOTHER VIDEO! thank you
it has been years since I was a field tech. While I didn't work in these wireless realms of rf, much of what I did is lateral to your specialty. I miss the work. I loved being in the field, and I loved to geek out on this stuff. I would bore the hell out of everybody around me and I never understood why everyone would roll their eyes.
Brilliantly explained! I am preparing for my Ham test and this is sure to help a lot.
Cheers!
Good luck on your test. KJ4RIV here ;)
@@CAGreve1231 Thank you and 73
Great demo and information Alex. I've learned more from your videos than i can remember. BTW, your dog wants his x5c.
Ed Arenz - I think that's what she was waiting for. She assumes I go outside only to play with her.
Both matter always. It doesn't matter the direction of the power transfer (into or out of the antenna), both the center and ground play the same role in the antenna radiation plot.
Consider it as a reference voltage. Electricity cannot flow unless there is a different voltage path for it to flow. Without the ground, there is no reference voltage (zero volts) to which the electricity can flow.
Very good explanation there, sir
Like the video - use of home made props was nice :) With the Vector Network Analyzers for testing SWR ..... its true professional equipment is hell expensive but you can buy decent budget testing devices like the MiniVNA products for a few hundred bucks.
... perfect demonstration, Alex :-) ... SWR so simple as that ;-)
Man great video!!
Thank you. This video is helpful.
very good explanation!
Very helpful thank you!
It all makes sense ! Thanks
Excellent!
Wow great video!
IT IS THE RATIO OF THE GREATEST VOLTAGE AMPLITUDE OF A STANDING WAVE ON A TRANSMISSION LINE TO THE LOWEST AMPLITUDE OF THE STANDING WAVE.
A lot of hams need to see this.
AS a HAM myself, I understand the confusion many HAMs have with SWR. Many just increase power to get the output they want.
Nice job... makes sense now
Great job thank you
verry verry nice explanation!
Got it. Thanks.
Great vid
Great. Thanks a lot.
Hi, I Would use on my Frsky XJT one antenna to have 6 or more fly km range. Which antenna do you recommend me?
All that and total radiated efficiency and realized gain.
do external wifi antennas on routers have to be swr tuned?
Thanks for this tutorial, I am an airline pilot and ham radio operator mostly CW, I learned in both scenarios that at least for HF antennas one should always look for a 1.0 in one of the many available meters for those frequencies. I understand the radiation pattern and particular needs are also clue factors, however I must say that regardless of those two factors a low SWR is always desired, not only to obtain the best possible signal but also to prect your equipment unless you are using an antenna tunner that tricks the transceiver?
svsoftair - In most cases and SWR of 2.5 is acceptable for most situations unless you are running up against the limit of your transmitter. Of course tuning devices are excellent for multi-band antennas and always a good idea. Ideally you have the radiation pattern you want and good SWR for a good system.
Alex Greve thanks a lot for your clarification
HI Alex, eating up all your info like free hotcakes... can I make a small suggestion though? you seem to use the word 'system' to describe a wide plethora of things... It could be just me..
So I understand what poor SWR does on the transmit side but what is its effect on the receive side? Does it just receive less of the signals power thus needing a more sensitive recover?
Wyll Surf Air Good question. It is the same thing, but in the opposite direction. In the case of a receiver, it receives a signal from the antenna. Thus you have the exact same system, but the exciter is the antenna instead of the antenna being the load. Basically it is me swinging the rope from the end attached to my deck. it makes no difference.
Does anyone know how the Taranis works out SWR? It feels like the number is displays are worked out differently. For example I have an antenna with an SWR reading of 17 and one with a reading of 32. Presumably the lower reading is better but how do those figures compare to what we normally see?
put a dummyload resistor( i assume its 50 ohm )across the antenna terminals and look at the measurement. That should be the 1:1 value anything higher would an unknown fraction worse but all relative to that.
Great demo Alex, shame the dog didnt get into it...Thanks...
please keep the dog on your shows We miss her...
Good
Great Alex. SWR being zero whould mean impdedences are being matched, and no power is being wasted. The signal plot gets into directionality, gain, and stuff. Right?
1.0 is perfection where the impedance is matched perfectly. The radiation plot tells the rest of the tale, yes.
Video Aerial Systems Thanks Alex. I guess the output power is a metric that needs to be examined. It sounds like some people did the antenna model themselves, got a SWR of 0 (On Taranis), but had no range. They probably killed the circuit. One way of treducing VSWR is to ruin the transmitter. LOL
So let me see if my thinking is right. If your swr is bad then your tx has more milliwatts used for getting the swr right and therefore means less range.
Kurtis Towery - Almost, but not quite. if you have low SWR, your transmitter wastes more power generating a standing wave and less power gets out the antenna.
3:46 dude feed your dog! Jk aside, this layman understand it much better ! Thank you!
Swr really matter in case of receiving only antenna??
I
Yes, it actually does. Remember that the only difference between a transmitting antenna and a receiving antenna is the direction of power flow.
So we've established VSWR is not exactly the ratio of the power coming out of the antenna compared to the reflected power. For example, an SWR of 2:1 with 100 watts input, with a lossless transmission line, would mean about 11 watts is reflected back. So that's a ratio of 89:11, or for easier comparison, 8.9:1.1 which = about 8.09:1. Anyway, that's hardly 2:1.
I was explaining in layman's terms, not reading from a textbook. Few people understand textbook language, but most understand basic demonstrations.
@@CAGreve1231 but it's not right though, is it? It's a different ratio. What is VSWR, and it's the first thing that comes out of your mouth. Yet all these people are saying, oh, I could never understand SWR and now I do. And, it's the best explanation I've ever seen, and I've had it explained to me by professors.
But it's fundamentally wrong, from the outset.
@@CAGreve1231 oh and, I don't think you've read it from a text book. You should give it a try. What's wrong with my definition, the language?
Background music/noise is distracting.
like
You barely explained why a low SWR may be desired, too busy tying a rope to your, um, deck.
And you said something about hitting resonance. Antenna resonance and SWR are two separate things. And then you jumped to antenna pattern which was somewhat irrelevant to the subject unless you explain why. And you did not mention resonance as an important factor either. I think you have just misled and even confused a bunch of people out there. Was this intentional because you don't really know what you are talking about in full?
I explained that if you were listening. I gave the rope an impulse and explained that the response was the resonant frequency.
Yep totally layman’s
If you paid more than $200 for a VNA then someone royally screwed you over. I dunno, maybe you got a really good deal on that RV, lol.
Why do you say that? Where can you find laboratory grade equipment for $200? I got these about 10 years ago and upgraded to vector voltmeter capability to measure axial ratio and emission power on my antennas. I don't know of any $200 device that can do that.
Jesus Loves You
This explanation is flawed people, but you'll lap up and praise anything on TH-cam.
Stop trying to take short cuts, read a text book and learn the right way, that is if you can read.
So what have you produced? Nothing? Oh my what a surprise! An internet troll criticizing a patented inventor. Do the World a favor and go play in traffic.
@@CAGreve1231 I'm not trolling at all, you are spreading misinformation and everyone is praising you for it. It takes for someone like me to keep this type of thing in check, I take my radio very seriously, and I worry about the future of it with so many like you on YT.
As far as my own production, I am not interested in doing that, and nor should I have to, it is irrelevant.
You need a lesson in manners, and if you were a real man, you'd own up to your mistakes and take it on board so things can progress without polluting people's minds with false theory. You could even thank me. But no, you go for the old troll routine and question what I have done in relation to radio. Mate, I've done a lot, including this.
@@CAGreve1231 and what's a patented inventor got to do with it?
I don't know what you've invented, and now frankly, I don't care. I hope it's not radio related. I know of a very popular antenna manufacturer with a prevalent yt channel, and he doesn't know about CMC, and he confused antenna resonance with SWR in his videos. Remarkable.
@@arconeagain - Dude, I am a patented inventor. You're an internet troll. Lot's of people like you. Go play on the train tracks.
@@CAGreve1231 that's a very poor attitude you have. Haha, and how many patents are out there? How many being used, sold, achieved?
Now tell me what Voltage Standing Wave Ratio really is without googling it. Tell me what we're really measuring here and why. First of all, what are standing waves.? I tried to point you in the right direction. I'm not a ham by the way, CBer here.
Excellent!