#278

[@w0qe]

Thanks for the nice comments Alan. SimSmith can solve a huge number of problems that are encountered in amateur radio and RF design in general such loss in antenna tuners, matching range of antenna tuners, RF power combiners and splitters, balun design and performance, crystal filter design, and much more. This a really nice time to learn these topics as reasonably priced test equipment and great analysis tools (free) are available. Larry, W0QE

[@yytvo212]

Really versatile "Love Smith Again" tool.

[@chongli297]

I love this. It's a little puzzle game! It becomes even more interesting when you want to try to build the network using components you already have on hand!

[@786jinga]

Never been soo excited about Smith charts.Your videos made me realize it's beauty 2 years after I finished my undergrad. Awesome Alan! loved d video

[@michaelmurray3422]

I added this program to my computer, and ran the 4 examples that you did, and WOW.... I like it. What a fun program, and very easy to use. Thank You for showing this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[@MichaelLloyd]

Alan, you and Larry (W0QE) have opened up a whole new world for myself and other Hams. Smith Charts used to be that thing you had to kind of know to pass the Extra exam. Now it's a genuinely useful tool. Thanks to both if you. NE5U

[@PixelSchnitzel]

Same here! This series from Alan just blasted down a barrier I've had in my RF learning progress. Alan and Larry, I can't thank you enough!

[@stevegilbert3067]

Learning to use Smith charts has been on my to-do list for a long time. Your videos about the Smith chart, along with the SimSmith program are a great help. Thanks!

[@Myke1576]

SimSmith has been a really nice, free, tool for quick matching networks :) It's been nice to see features added over the years and hope the project continues.

[@Radiowild]

That's a neat program. Makes finding the right network fun as "L", and easy as "Pi". Or was that Pi-L. Thanks for showing.

[@singlehanded12]

Great info, really enjoying this smith chart series, beginning to understand the need for a deep dive into antenna/impedance theory rather than just plugging into an analyser or tuner.

[@willhelmx8388]

Hi guy´s, this is a fantastic program to use, takes away much of the time consuming calculations and also gives you the possibility to analyze cirquits and to build your own "blocks" of data/circuits for later use... Excellent, thanks u all..

[@greghorine4995]

Thanks for another great video. I've been playing with SimSmith, between that tool, and your videos, I've actually learned stuff I can use!

[@harry4516]

1+++ for pointing us to SimSmith. I didn´t know this program, but wowww, thats really one of the best software I used for long.

[@w2aew]

And please check out Larry's channel, he has tons of excellent tutorials on the use of SimSmith. kzbin.info/door/KSyLSu4fm_1RHoO3Jvk4YQ

[@billmoran3812]

I love graphical solutions. SimSmith looks like a great tool.

[@Cptnbond]

Thanks a lot, making Smith charts understandable by practical examples, and SimSmith is great!

[@VikasVJois]

Thanks for introducing W0QE's channel. Awesome videos. Subbed

[@JoseSilveira-newhandleforYT]

Great simple video. I'm starting to like Smith Charts, thanks to you. Good job, as usual :-)

[@LaboussoleNano]

Hello, Thanks again for the video, I watched it twice. I have a question. Can the frequency of the inductance and capacitance influence the matching process? Same question for the quality factor. I see that in the SIMSmith table we have a part to fill in the frequency value of the inductance and capacitance. I also see in the capacitance data sheet that they have an impedance vs. frequency curve. Should all of these characteristics be considered when choosing the value of the matching elements? Thanks.

[@ornithopterindia]

👍Thank you sir.

[@nvrumi]

None of the material I've looked at explained the use of the Smith Chart until this series. Thank you so much! Now, what happens if we consider losses in the feedline? I am really interested in learning how to analyze the antenna system including the impact of feedline losses so I can understand how to design and build antennas. I am (and was) aware that the complex impedance of the feedline affects SWR readings at the input to the feedline. What I'm trying to understand is how to get from what the meter is telling me to how to adjust the antenna and feedline for best performance. Does that make any sense?

[@w2aew]

Actually, the length of the feedline does NOT affect the SWR, but is DOES affect the input impedance seen looking into the feedline. Loss in the feedline will make the SWR *appear* lower because the reflected energy is attenuated on it's return trip back to the transmitter (makes the trace approach the center of the chart).

[@Jackofalltrades837]

Wow what great videos, thank you for sharing your knowledge.

[@robertcalkjr.8325]

Very nice Alan. Mega thanks!

[@bblod4896]

Cool, have to try this out. Thank you.

[@daveturner5305]

Alan, I always enjoy your tutorials. They are well thought out with no waffle, little repetition and are not too long. Unfortunately I was not able to fully enjoy this video as there was insufficient contrast in the screen capture for me to see details in the chart. Perhaps you could find a way to improve this; or am I the only one having problems viewing this video?

[@richardlmontel]

In SimSmith there is very little detail in the on screen smith chart. Paper charts need the detail, as that is where you have to get the information. The program prints the actual numbers elsewhere on the screen, so you don't need to squint trying to interpolate the correct answer from the chart. The chart actually looks has that faded look in the program, and it is done on purpose.

[@wemme]

What ham radio/rf forum do people recommend? Also thanks for the smith chart content. Well done as always

[@w2aew]

Typically the forums on www.eham.net and www.qrz.com are fundamentally focused on ham radio - some sub-forums are more technical. There is also a RF, Microwave, Ham Radio subforum on the EEVBlog forum.

[@cescofran6165]

But this can be done at the transmitter output as well or is it another story? Bacause I usually see some kind of PI low pass filters but I can't undestand if they are also used for impedance matching.

[@wolleausmallo1]

Best program ever.

[@btouw8558]

Yes, i like the video and give you a big tumbs-up

[@CH_Pechiar]

Alan, could you show how measuring a load (an antenna) connected via a arbitrary lenght of coax affects the reading (if the antenna is not resonant)? I understand it does, hence the OSL procedure on some instruments. Thanks.

[@w2aew]

I describe the effects of a transmission line on the measured impedance looking into the line, in video #275, starting at 5:16. The OSL procedure is used to establish a new measurement plane at the point of the load or DUT attachment, by de-embedding the impedance transformation added by the line.

[@CH_Pechiar]

Thank you. Very clear, but if I'm not mistaken, if you measure the load with an arbitrary length of wire and the result of the measurement the VSWR is 1:1 then the load by it self MUST be resonant too, as the effect of the transmission line whould be rotating on the centre of the chart. I always thought that there was a chance of getting a 1:1 VSWR redout of the combination of the load and transmission line but the load by it self not being resonant (eg, measuring 1:1 at the transmitter side wouldn't imply a resonant antenna). Correct?

[@w2aew]

Don't confuse *resonance* for a impedance match to the system impedance (or transmission line impedance). *Resonance* means that the reactive component of the impedance is zero. Resonance does NOT mean a perfect 50 ohm impedance, nor does resonance mean a 1:1 VSWR. Many people think it does because most antennas are designed to have a resonant impedance of 50 ohms (but not all of them do). VSWR does not depend on, or change, as a function of the transmission line length (as long as the loss is negligible). But, the *input impedance* looking into the line WILL change as a function of line length for a line-to-load mismatch. If you have a load that has a 2:1 VSWR (in a 50 ohm environment), the constant VSWR circle will pass through the real axis on the smith chart at 100 ohms and at 25 ohms at certain transmission line lengths. These are resonant points, but not matched to 50 ohms, and still give 2:1 VSWR.

[@CH_Pechiar]

Yes, I understand that, no problem. I tried not to tie my question to a 50 ohm environment and therefore the mix of terms. Anyhow, back to my question, If you measure VSWR 1:1 at the the transmitter side (in a 50 ohm environment) then the load (antenna) must be 50 ohm resistive, independent of the length of the wire, correct? If so, my assumption that a 1:1 VSWR at the transmission line could make you think that the load (antenna) may not be 50 ohm resistive is not correct. Correct?

[@w2aew]

Correct. If you measure 1:1 VSWR, then the load has the same impedance as the transmission line (50 ohms, no reactance, for example), regardless of transmission line length. It could also mean that the line is *very* lossy, to the point where the reflected power is dissipated/lost before it gets back to the transmitter. This is a less likely scenario, but it would result in a (potentially false) low VSWR reading when the load is mismatched - but it would have to be a long lossy line...

[@bobkozlarekwa2sqq59]

A+, thanks for sharing

[@suryo1269]

Hello, Thanks for the video . I'm wondering on how to add parasitics reactance components in the generator (adding impedance) instead of pure resistive Zo ?I'm trying to simulate L matching network between amplifier(z output transistor/mosfet and load). Thx alot

[@w2aew]

You can reduce the resistor in the G generator, then add additional components in series to simulate a complex source impedance if needed.

[@namename8986]

How do the calculations work when there are more than 2 stages?

[@joopterwijn]

Thx, very need site!

[@baghdadiabdellatif1581]

Thank you

[@TheRetiredtech]

Great info. I wish I understood this 50 ago.

[@LaboussoleNano]

Hello, I am beginner in antenna design and tuning. . I want my antenna to have a resonant frequency of 2.45GHz for Bluetooth low-energy communication. And I want to know which point to consider for the matching process. I have made some measurements with Nanovna of my antenna. I have a resonant frequency of 2.28GHz and at this frequency, I have an impedance of 47.8-7.06j. Could I take the value of this impedance at that frequency and change the frequency to have 2.45GHz. Or I must take the value of impedance at 2.45GHz and process to the matching process?

[@w2aew]

You will need to use the impedance measured at 2.45GHz.

[@LaboussoleNano]

@@w2aew Okay thanks

[@cmuller1441]

My PC has also a quite noisy mic input and the way to fix that is to buy an usb mic. This can be expensive to get a good one. A cheaper way is to buy a $10 usb audio device with a mic input. It's not ideal but it's an big improvement over a bad pc mic input.

[@w2aew]

Thanks - I think I'll invest in a decent USB mic. Sorry about the crappy SNR on this one...

[@cmuller1441]

Thanks for all your great videos. I searched a bit and you can start with that kind of cheap devices amzn.to/1Pds77X if you don't want to spend $100 or more...

[@cmuller1441]

kzbin.info/www/bejne/Y4KWYZVnnZ56bZI

[@w2aew]

Hmm - looks pretty cool - cheap too. So cheap in fact, that I'd have to add it as an "add on" to get it on Amazon prime.

[@nreitcheck]

Another option is the Audio Technica ATR2100-USB or AT2005USB microphone. There are several dozen KZbin videos as well related to these microphones.

[@23RaySan]

for those linux fanboys out there: i can confirm that it will work with linux and the oracle jre

[@786jinga]

Was about to add that comment! LOL!!!

[@tzimmermann]

I was just going to post that! Fantastic piece of software, by the way.

[@indigoskywalker]

Cheers, seems there are several of us linux fanboys.... 😂

[@АндрейДенисюк-ш7п]

OpenJDK 11 is also OK

[@fishyrider3528]

Thx. Great.

[@neuralnetwork653]

Thank you!

[@markuscwatson]

Verry cool

[@kaybhee6]

keen

[@radekkierzek6853]

I prepare video with noise reduction if You want, I send to You.

[@w2aew]

Thanks - but I don't think I can replace the video on KZbin anyway. I appreciate the offer, thank you.

[@radekkierzek6853]

It really lacks this function on YT

[@aymanmoussaoui1221]

Hi w2aew, I sent you a message in KZbin where I suggest some Important Electronics Projects, so you can check the received messages in your channel on KZbin, Thank You.

[@fredgarvin9262]

When in doubt, don't bother calculating. Just load an app and start screwing around?

[@w2aew]

In my previous couple of Smith Chart videos, I do show how to do it all manually. The software makes it faster to run the experiments - but you should still have an understanding of how the chart works, and the effects of adding tuning elements.

[@6alecapristrudel]

noisy