Single shunt stub matching network using smith chart by Dr. Niraj Kumar VIT Chennai

[@viratchinna7099]

Even paying coaching centres can't explain like this .Thank you so much sir

[@RFDesignbasics]

That's so sweet.. Thanku for the appreciation.

[@rodericksibelius8472]

Great Video, Thanks Professor, You make it so clear Teaching this, I read and watch all kinds of video explanations regarding this topic, Your Video is easy to grasp. I took a Microwaves Electronics Technology Class way back in 1985, for 9 months in a Microwave Training Center learning about Klystrons, magnetrons, Network analyzers, S-Parameters, but the use of the Smith Chart for practicality and ease of use was NEVER REALLY understood the way we were presented in Class. I am now retired and still re-learning these fundamental concepts.

[@RFDesignbasics]

Thanks a lot sir. I was not even born that time. Happy to help you.

[@jonathaniniguez2897]

Thank you so much I finally understand this concept after hours of trying to learn it.

[@AmitKumarSahoo]

Niraj Sir, this video is extremely helpful to me. I am in University of Glasgow here. I am studying this subject for new and getting a lot of insight on this when it's worked out here with a clear perception and understanding. This is quite good for new learners of Basics of RF and microwave.

[@RFDesignbasics]

Thanks❤

[@AmitKumarSahoo]

​@@RFDesignbasics Sir, I just passed with good grades in Microwave engineering subject. Thanks to your helpful videos. They were far more comprehensive than our lecture materials here at Glasgow University. I have another subject called DSP where I have to design FIR and IIR filters . Can you please suggest my any good professors who teach online from VIT for DSP based Python programming for filters?

[@RFDesignbasics]

Congratulations🎉🎉🎉 send me an email from the about section. I will reply.

[@mandarbamane4268]

This saved my final year viva in RF. It was online class in 2021 and we didn't learn $#!t and were doing project. I didn't even know R in RF & they were taking like literally 5 mins per student & I wasn't prepared (although they asked everyone what you've studied, and then started screwing students within same topic). I somehow managed to talk stuff from this video (single stub matching) and I successfully managed to extend my bull$#!t for 5 mins. And thank you very much, you saved my @$$ (from getting humiliated unlike others).

[@ogulcankacar6266]

Greetings from turkey good job sir.

[@chahlahicheur7085]

This video is very helpful to me . Thank you so much sir

[@hvk3929]

Thanks bro.. You don't how much this video helped me..

[@andresmartinezmera9077]

Thank you for this video. It's a good refresher. I usually design matching networks with the ADS Smith Chart tool and with the RFdude tool. I've almost forgotten how to do that the old way...

[@kr1shi]

Thank you sir! Your solution is clear and well explained.

[@bwharris2002]

Thank you! This was extremely helpful.

[@АлексейБоярченков]

Exactly what I'd needed! With reasoning. In short, we're searching an unknown Z, that should be connected in parallel to (part of line + unmatched load), for having exact 50+j0 at point of connection! (and how to deal with Shith chart calculkating parallel connections impedances) I've got it! Thank you.

[@RFDesignbasics]

Welcome

[@devopswallah]

thanks a lot sir student of vit chennai but still learning on ur channel

[@user-uv4xe3cq2y]

Very clear, very helpful. Thanks for your video.

[@RFDesignbasics]

Thank You

[@shantanuanand4679]

Thankyou Sir, you just saved me in my CAT2 examinations please visit vellore campus soon .....

[@vamsimohan5369]

No bro we need him in chennai campus 😂😂

[@kayicomert7933]

Thanks a lot for this lovely vid. You are really good at explaining!

[@RFDesignbasics]

Thanks and welcome

[@hukaihua7513]

Sir, @10:27 matching the imaginary part, why we are not using the final value(0.25lambda) minus the initial value(0.344lambda)?

[@eya_ounissi]

Thank you for the explanation 😊

[@danielnaicker2142]

Thank you so much for this video!

[@syarifuddinsakri7008]

Thank you sir. Very helpful. 👍🏻👍🏻👍🏻

[@ushakiran1103]

best explanation

[@omaryahia]

Thank you sir , very clear explanation 👍

[@RFDesignbasics]

Thanks a lot.. Do not forget to subscribe and share with your friends.

[@gowthamanjaiganesh3210]

hi sir just few doubts like how come you got 1+1.5j value and then how you marked 0.344 lambda and how ls is calculated by subtracting 0.344 lambda - 0.25 lambda

[@rayankgoswami6131]

Thank you very much sir

[@felicityoswald6159]

we used short stub for single stub matching technique. I have two questions: 1-) If we use short stub how does our impedance move on smith chart? On VSWR circle or constant impedance circle? 2-) What if we use open stub instead of short stub, how should we move on smith chart? Is there any explanation regarding these two "movements" on your videos? Thanks in advance

[@RFDesignbasics]

Irrespective of short or open, movement will be always on constant vswr circle.. Only when you calculate the length of the stub, take starting point for short or open stub from short or open circuit respectively on admittance chart. Hope it will help.

[@peppepeleo6219]

Thanks a lot for this video. I have a question: if the frequency of the problem changes, what does the problem change? We can always consider matching network or some else? Thank you for attention.

[@RFDesignbasics]

Thanks❤

[@hassanrabbani3221]

Why we subtract 0.25 lambda in the end to calculate Ls?

[@nickpenacl_]

Thanks , just missed to see the open circuit example , another solution

[@AVATAR_S]

sir can you say important topics for FAT

[@armihamradio6452]

Thanks for the tutorial sir

[@RFDesignbasics]

Thanks 🙂

[@nikhilsunilkumar1]

Done well Thank you sir

[@asish8880]

How did you get the lamda values early,??generally i take angle and convert to lamda form🙄

[@RFDesignbasics]

There is lambda scale as well.

[@akleshkumar1759]

sir last main aapne 0.25lameda q subtract kiya , samajh nhi aaya

[@Shrikant_Darade]

What about if we want to add open circuited stub...? Is process will remains the same or different

[@RFDesignbasics]

Everything remains same except the last part for stub length calculation. Length will be calculated from the left side of the smith chart for open ckt where Z = 0.

[@Shrikant_Darade]

@@RFDesignbasics thank you sir for your reply...! It got cleared...

[@swethachilveri4123]

That was 1+jx circle right?

[@RFDesignbasics]

Yes. It's called 1+jb when working on Y-chart

[@swethachilveri4123]

@@RFDesignbasics Ok Sir.

[@conesillyvalley7182]

So the shunt 0.094j has to be de-normalized by multiplying by 50 ohms right?

[@RFDesignbasics]

No! That is susceptance. First convert to reactance by taking inverse then multiply by 50 ohms

[@conesillyvalley7182]

@@RFDesignbasics yes, forgot about that. Thanks!

[@nareshkumaar2753]

Super thank you sir👍👍👍

[@RFDesignbasics]

Most welcome.

[@bt9604]

M.A college of Engineering, kothamangalam daaa😎😎😎😎😎😎

[@vidhishah759]

Hello sir, Thanks for the video. Sir,how do you found out the stop point at resistance circle.. Did you take it random? Waiting for your soon response Thank you in advance!

[@RFDesignbasics]

Hi.. Stop point is on unit resistance circle.. for first solution u need to stop at upper half of the circle and for the second solution, lower part of the circle.

[@vidhishah759]

Thank you sir.. I got it! 😊

[@keerthipatnayakuni814]

Good afternoon sir...if the numericals changed to 100+j650 and 300 ohms...what will be the solution??after finding normalised impedance how can we mark o.3+j2.1 in the Smit chart??.....I am waiting for your response sir...

[@RFDesignbasics]

It's simple! Just find out 0.3 on resistance circle and 2.1 on reactance circle and intersection of these two points in upper half will be normalised load impedance point. As explained in the video you should move exactly opposite to this point as a first step of single stub matching i.e. load admittance point. Follow remaining steps too.

[@همسهناعمة-ك4ه]

Thank you very much

[@pelusopj]

Hey man great video! Would you be able to describe in detail how to get the other solution? I understand you have to go the opposite direction on the VSWR circle but I am not sure how the math follows after that?

[@RFDesignbasics]

For other solution, you have to go to other side of unity circle (bottom side) and follow the same procedure.

[@pelusopj]

@@RFDesignbasics Thank you for the quick reply. So would this short circuit shunt be considered lossless?

[@RFDesignbasics]

All of these are only valid for lossless transmission lines.

[@shubhamkapoor8756]

In some of the matching problems i worked on,i noticed that sometimes physical generator is not considered and direction towards generator is considered even if it looks like we should be going towards load for measuring.Can you explain how is this decided

[@RFDesignbasics]

Send me an email with the question, then I may be able to help.

[@b56rudrakalyan62]

thank you sir

[@AD-ft1mf]

sir can u give a demo about oc stub like how it's going to be solved ty

[@RFDesignbasics]

It's all same except the length of stub. Starting point for calculation of stub length will be from left side of the smith chart. Difference of length of OC an SC stub is always 0.25 lamba. E.g. if short ckt stub length is 0.1 lambda then OC stub length will be 0.25+0.1 = 0.35 lambda. If SC length is 0.4 lambda then OC stub length will be 0.4-0.25 = 0.15 lambda.

[@AD-ft1mf]

ty sir

[@SalamaOmarSalama]

Why we use short circuit at shunt and open circuit at series?! Why we don,t use open circuit in this example?

[@RFDesignbasics]

Open and short circuit will be just 0.25lambda apart from each other.

[@rameezreviews]

Good

[@nihalsingh6419]

Sir that short circuit line has characteristics impedance of 50 ohms what if it has characteristics impedance of 100 ohms

[@RFDesignbasics]

I understand from your question that. The main line is 50ohm but stub is 100ohm. In that case divide the obtained b value with 50 and multiply by 100 and than find length using Same method.

[@nihalsingh6419]

@@RFDesignbasics thanks sir ,

[@RFDesignbasics]

You are welcome 👍

[@anistalha452]

this is for open or short circuit ?

[@RFDesignbasics]

This example is for short circuit shunt stub.

[@anistalha452]

@@RFDesignbasics ohhh alright. If i want to do for open circuit shunt stub, do i need to measure the length from 0 value from the left hand side?

[@RFDesignbasics]

Yes

[@anistalha452]

@@RFDesignbasics thank you sir

[@heetha4281]

Sir how you are subtracted at Ls side 0.25 lambda

[@RFDesignbasics]

soundarya bagula if you are using short circuit Stub then u have to subtract 0.25 lambda to find ls. If it is open circuit then no need to subtract.

[@heetha4281]

Sir I have one question related to Smith chart single stub matching am not getting correct answer would you please give any mail id for the send that question

[@heetha4281]

Thank you sir

[@flick5314]

🙏

[@uttam6681]

How 1+1.5j came sir

[@LORDALPHA]

If you look at the smith chart the point intersects two lines, one is 1.0 and the other is 1.5 so when placed in the cal they are 1+1.5j

[@RFDesignbasics]

Thanks for the explanation!! I missed the comment.

[@thewitcher8658]

It has 2 solutions, you only showed one.

[@mdnoorzafirmondal7398]

What is ds? Is it distance between antennae and stub?

[@RFDesignbasics]

Yes 👍

[@mdnoorzafirmondal7398]

@@RFDesignbasics thnq

[@tejashrighanekar6818]

In ls calculating why u are substract 0.25lambda

[@RFDesignbasics]

0.25lambda is point for the short circuit stub on admittance chart i.e. open circuit on impedance chart.

[@riseabovehate9476]

How to do for Open ckt stub ?

[@RFDesignbasics]

Just take the other end as starting point for all the calculation of length. Magnitude of difference betweenOpen and short circuit length will be always 0.25. So thumb rule is, if SC length is less than 0.25lambda, add 0.25lambda to get OC length. If SC length is more than 0.25lambda reduce 0.25 lambda to get OC length. In both the cases distance of stub will remain same.

[@riseabovehate9476]

IF this is one of the solutions. Then what is the other one.

[@RFDesignbasics]

Other solution is, if you move on constant vswr circle and reach negative on 1+jb circle in the negative side rather positive side.

[@gajjalanvlraviteja5715]

Tq sir

[@RFDesignbasics]

Welcome.. subscribe and share 🙂

[@govindraut4130]

Hlw sir how to making s-matrix from double stub matching network problem??? Plz solve

[@RFDesignbasics]

Couldn't understand your questions

[@akshatwaghmare4065]

👍🙏

[@ritambiz]

i love you

[@AYUSHKUMAR-gj3sb]

niceeeeeeeeeeeeeeeeeeeeeeeeeee

[@gauravphalke5311]

4:05

[@akashrana3052]

take more example

[@michaelcoletti6217]

thank you~!

[@RFDesignbasics]

Welcome