nanoVNA: Measuring the Input Impedance of a Filter (068c)

[@WECB640]

Outstanding as always Ralph. Keep up the excellent work. 73

[@eie_for_you]

Thanks, man! 🙂

[@chrisgardner2548]

Ralph, I really appreciate the outstanding videos, and the boundless knowledge you freely share in the true spirit of giving. Thank You!!!

[@eie_for_you]

Thank you for the encouragement! ... and you are very welcome! 🙂

[@Ghostpalace]

Thank you! Love the john 3:16 sign

[@eie_for_you]

Thanks, man! 🙂

[@AlexejSvirid]

Here is Christ's question, Mathew 15: 3: "But he answered and said unto them, Why do ye also transgress the commandment of God by your tradition?" Malachi 2: 1-4: "And now, O ye priests, this commandment is for you. If ye will not hear, and if ye will not lay it to heart, to give glory unto my name, saith the LORD of hosts, I will even send a curse upon you, and I will curse your blessings: yea, I have cursed them already, because ye do not lay it to heart. Behold, I will corrupt your seed, and spread dung upon your faces, even the dung of your solemn feasts; and one shall take you away with it. And ye shall know that I have sent this commandment unto you, that my covenant might be with Levi, saith the LORD of hosts." A women say "the Husband has no name". Another ones say "the Husband has many names". Some of women "love the Husband in all his manifestations" like: neighbour, taxi driver, coworker... But, all of those prostitutes say "the Husband is the only". Then they even talk about "trinity of the Husband" and they are not against "the Son taking the Husband's place". In the same way religious prostitutes try to hide their disgusting fornication with different gods. Furthermore, a correct pronunciation of the Name is unknown now. This is the “loyalty” of traitors! Here is the God's word spoken through Moses, Deuteronomy 11: 16-17: "Take heed to yourselves, that your heart be not deceived, and ye turn aside, and serve other gods, and worship them; And then the LORD's wrath be kindled against you, and he shut up the heaven, that there be no rain, and that the land yield not her fruit; and lest ye perish quickly from off the good land which the LORD giveth you." So, the God says there are other gods, but blind leaders of blind lead people into trap. "Jesus" means "Jehovah is salvation". This is the name of Christ real christians are hated for. "HalleluJah" means "Praze Jah" (Jehovah). Psalm 83: 18: "That men may know that thou, whose name alone is JEHOVAH, art the most high over all the earth." The problem is Devil runs the world. He is lier and murderer. This is the reason why liers feel so good while righteous people are persecuted. That's why we've got the Gospel about the God's kingdom. Jehovah would put everything in order. The dead will be resurected and we'll meet our beloved ones again! :-)

[@Studyelectron]

Your explanation and your personality too match like matching starting point of Antenna via all receiver stages to loud speakers in between travel from head end to the viewing and enjoying your wisdom treasures

[@eie_for_you]

Thank you! 🙂

[@wb7ond]

Great video, even though I am fairly skilled with the NanoVNA, I still pick up cool hints on its usage, for example, for some reason it never occurred to me that the smith chart was scalable... That is pretty cool... Other subtle hits are also great along the way. Thanks for these great videos... Regards

[@eie_for_you]

You are right ... it is scalable as it is the "normalized impedance" of whatever you are working with. I'm so glad that you find the videos helpful. That is my #1 goal. 🙂

[@Studyelectron]

Thanks impedance matching important factor to transfer transmission and altering impedance to match from source to load without loss of efficiency and power

[@eie_for_you]

You are welcome! 🙂

[@michaelrestivo1047]

Thank you again Ralph for another great video! I do have a question please about how you calculated total impedance. If R is 52 Ohms and jx is +5.56, how do we arrive at 52.3 total ohms of reactance?

[@eie_for_you]

I'll point you to this video which will explain the answer to this question much better than I can easily do in a reply to your comment: kzbin.info/www/bejne/amm1f6Frqb2qaMk 🙂

[@W1RMD]

Wonderful, I'm just getting into this subject matter myself and as always, you post a video at the perfect time! I know I should know Will you gives us some details on the filter design or if you have a video on it let me know? I'm using my NanoVNA to measure I.F. transformers on a receiver I'm working on from 1940. Also, can you do a video in the future on band pass vs. high pass, vs. low pass filters using a VNA. I know that's a lot, but just ideas for future videos if you need any. Thank you for all you do, take care and 73!

[@eie_for_you]

Well, I'm no filter wizard either as you will see in the next video on this filter's frequency response. I used an online filter designer which gave me values that I didn't have, so I cobbled together something and some components weren't the value I *thought* they were and, by the way, a wire jumper has inductance which can through tings off ... you get the drift. Part of the problem was the frequency that I was trying to set the filter for and the hacked and cobbled nature of the implementation. Those video suggestions sound like fun. I get to cobble together some more filters and maybe even learn something in the process! 🙂

[@W1RMD]

@@eie_for_you That's why we're here and the NanoVNA makes this a MUCH quicker job. I'm looking to make a filter to put in front of a preamp to monitor 134.95 Mhz ZBW ARTCC site to monitor high altitude air traffic, but the site is about an hours drive from here. I've been barely been able to copy the center with a scanner standing on the roof holding a small beam antenna. A good filter is a MUST for not amplifying a bunch of garbage as well. 73!

[@eie_for_you]

@@W1RMD Yes! I see the need! I tried a filter designer app ... unimpressed with the results. There are a BUNCH of them out there. I'd really like to totally understand how to go back to basics and design my own instead of depending on someone's app. That would be real nice. But, like so many other things, "if you don't know, I'm not going to tell you!" 😞 We'll get'er eventually! 🙂

[@W1RMD]

Sorry, I meant RCAG site not ARTCC site.

[@eie_for_you]

@@W1RMD Gotcha! 🙂

[@ornithopterindia]

👍Thank you sir.

[@eie_for_you]

You are welcome! 🙂

[@donepearce]

When you changed the scale to 0.2 the data changed appropriately but the smith chart behind it did not. It remained at unity scale. Have they fixed this yet?

[@eie_for_you]

Honestly, I never paid much attention to the lines. I look at the numbers associated with the marker. If they fixed that, I haven't updated mine with the new firmware. 🙂

[@donepearce]

@@eie_for_you OK. For me the lines are the key, and the numbers are just detail. The lines tell me what structures I need to move a marker to the centre.

[@eie_for_you]

@@donepearce Aaaaah! I see. 🙂

[@minazulkhan8287]

Hi, john can u make video on 'The Thing ' (listening device). Would u like to make and explain something like that

[@eie_for_you]

Sorry ... this would be significantly out of my realm of interest.

[@W1RMD]

@@eie_for_you I wonder if this comment was meant for another person's video? I have (my screwed up computer) left comments on the wrong video before. Other than that, the "Carlson Super Probe" comes into mind.

[@2321brendan]

Nice thanks. IS it possible to measure component Q or more specifically ESR of component at freq of interest. I would like to measure inductor R at freq X . Seems like there must be a way with this device. I have seen the method at self resonance that uses 3db width,but I dont want to use the component at self resonance. I want to use it far from There! Did you get your new toy? and try the free SA software?

[@eie_for_you]

Thanks! yes, you can determine the Q of a component at a specific frequency. The Q of a component is the reactive part divided by the real part of its impedance at a given frequency. (X/R) It sounds like the stuff you have been seeing might be referring to the Q of a tuned circuit as opposed to a component. The Q of a tuned/resonant circuit is the frequency of resonance divided by the bandwidth (-3 dB points) (fo/BW). Two videos of interest on the subject are Q: kzbin.info/www/bejne/g2esoWSnoMhre68 Measuring Impedance of a Component: kzbin.info/www/bejne/hqXMaXiorMR-ock I am still waiting for its arrival (impatiently). Where do I get the free SA software? 🙂

[@2321brendan]

@@eie_for_you Thanks. Not sure whats happening to my comments. They keep disappearing. Google : spectrumanalyser . co . uk Dont think it will load up without RSP1 connected. However the manual is available on that site. I was not aware a VNA could measure R of a component down to milliohms. My old Noise bridge is jumpy down below 10 ohm due to jumpy potentiometer.

[@eie_for_you]

Just got the toy late yesterday. So far it is AWESOME and I have found the SA software. While, in some ways, it is not intuitive, it is also quite awesome. Took me a bit to figure out how to change the RBW. Still haven't figured out the markers. I'll get there. 🙂

[@2321brendan]

@@eie_for_you Excellent . I jave been trying to Reply .However YT keeps losing my comments. Tried about 10 times. I did not realise the Nano VNA was capable of measuring R down to milliohms . My old noise bridge is poor below 10Ohms. due to potentiometer jumping around. Looks like nano vna is on the shopping list.

[@eie_for_you]

@@2321brendan Be aware that all VNAs have some issues measuring down into the milliohm range. With that said, they will report what they measure but these measurements may vary widely. I still recommend having a nanoVNA as they do a totally awesome job of it. See the links in the description for the "genuine article." 🙂

[@tomstrum6259]

Unless this is an intended Comprehensive NanoVNA introduction aide, you seem to be doing a Lot of excessive"Tapping" & screen setting work that I don't need to do using my NanoVNA-F to make same S11 measurements....Why not Calibrate (Open, Short & Terminate) using the Same coax cable & Eliminate all the port Extension set-up work ?? .....Thx for showing..

[@eie_for_you]

I cannot assume that the person watching the video knows how to navigate the various menus. There are a LOT of folks out there who just got the nanoVNA and are trying to figure out how to use it. Thus, I am not going to skip steps that they would find useful. Like I said in the video, I purposely did this the way I did it so I could demonstrate how to do a port extension. I said the easiest way to accomplish this would be just to convert to an N connector and calibrate with my N standards. But, not everyone had N standards to do this with, and folks need to know how to accommodate those situations where they have to add or remove an adapter to do the measurement. Thus, I purposely did this in such a way as to give myself the opportunity to demonstrate how to do it. 🙂

[@tomstrum6259]

Thx...As a relatively beginner user of the NanoVNA-F maybe I've been doing something wrong...My most usual Specific Swept freq S11 antenna & Device characteristics concerns are Return loss, Resistance, Reactance & R+jx Polar....Since across the Bandwidth (Hf,Vhf,Uhf) I see Insignificant minor effects when switching between typical connector Adapters...I rarely measure Phase when my primary Characteristics (RL, R, X, & Polar) BW are so little affected by typical connector Adapters changes...Should I be concerned with Phase ?? ....Thx

[@eie_for_you]

@@tomstrum6259 As you probably already know, as you move down a transmission line from the original impedance, the actual impedance as measured at the end of the transmission line will be different. This transformation is in terms of the number of wavelengths you are from the original point. At the 1/2 wavelength point (electrically speaking), the impedance, once again, returns to the original value (see the Smith Chart). Thus, the phase associated with the frequency in question determines the place along that transformation you are at. As you can guess, the higher the frequency, the more distance from the original calibration "reference plane" becomes more and more significant in the measured value of the impedance because the wavelengths are shorter. By doing the "port extension" we are moving the "reference plane" of the calibration to the place where we are connecting the item to be measured. Thus, we are actually measuring the impedance of the DUT, not the impedance of the DUT as transformed by the transmission line (again, the Smith Chart). So, yes, this method of adding delay (phase) is necessary IF we want the most accurate measurement possible. Oh, and this is really only needed to be done when measuring impedance. The Return Loss, SWR and other such entities are a don't care on this point *unless* we encounter a faulty adapter that we are adding. Again, going back to the Smith Chart, the RL and SWR in a lossless feedline are unchanged by the distance from load or source. Only the composition of the impedance changes - but always in a way to keep the RL and SWR constant. Hope this helps. 🙂

[@Studyelectron]

Teaching and learning are age old law of grace from one to the other by igniting or spark

[@eie_for_you]

True that. :-)

[@ahmedalshalchi]

You have quoted the Bible ( John 3:16 ) on the background ... I wonder what would you comment on ( John 17:3 ) and who is Jesus praying to and why ?!...

[@eie_for_you]

The first rule of proper Bible interpretation is context. You want me to comment on John 17:3. You ask, "Who is Jesus praying to?" Backing out to the context of this verse easily answers this question. In John 17:1 we read, "When Jesus had spoken these words, he lifted up his eyes to heaven, and said, “Father, the hour has come; glorify your Son that the Son may glorify you,..." So, the answer to the first question is God, the Father. Why is He praying to God the Father is your next question. This is in the middle of what is often called Jesus' "High Priestly Prayer." He is looking toward His willing sacrifice of Himself on the cross to pay the penalty for the sin of mankind so that we all, through faith in that finished work, can enjoy salvation and fellowship with God through Him (Jesus). This salvation is made available to all people, everywhere as a free gift to be received by faith. He is praying for all of those who will put their faith in Him as Saviour and preparing Himself for what is to come. The Bible clearly tells us that everyone has grievously sinned against God. Paul quotes Psalms 14:1-3 and Psalm 53:1-3 in Romans 3:10-12 where we read, "...They are corrupt, they do abominable deeds; there is none who does good. The LORD looks down from heaven on the children of man, to see if there are any who understand, who seek after God. They have all turned aside; together they have become corrupt; there is none who does good, not even one." The end of that state is eternal punishment in hell referred to as the "second death." Romans 6:23 says, "For the wages of sin is death ..." But, there is good news at the end of that verse when we continue reading. It says, "... but the free gift of God is eternal life in Christ Jesus our Lord." Why is this? Because Jesus paid the penalty for our sin on the cross. We read in Isaiah "All we like sheep have gone astray; we have turned-every one-to his own way; and the LORD has laid on him the iniquity of us all." But, like any gift, it does us no benefit unless received by the one it is offered to. It is not received by doing good works or by being religious or giving money to some organisation or anything else that we could do of ourselves. Otherwise salvation would be something owed to us and we would get the glory for it. Titus 3:3-7 says "For we ourselves were once foolish, disobedient, led astray, slaves to various passions and pleasures, passing our days in malice and envy, hated by others and hating one another. But when the goodness and loving kindness of God our Savior appeared, He saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, whom he poured out on us richly through Jesus Christ our Savior, so that being justified by his grace we might become heirs according to the hope of eternal life." Notice ... the "loving kindness of God our Saviour" and then "poured out on us richly through Jesus Christ our Saviour..." This connection (God our Saviour Jesus Christ our Saviour) clearly indicates the Deity of Jesus as does the first chapter of the Gospel of John. We also have Ephesians 2:8-9 which says "For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast." So, Jesus was praying to God, the Father, in anticipation of His immanent, willing sacrifice of Himself as the "Lamb of God which takes away the sin of the world" (John 1:29), praying for those who would put their faith in Him to find eternal life with God.🙂

[@ahmedalshalchi]

@@eie_for_you Thanks Mr. Ralph , for all this explanation ... So , the Son of God was praying to the God The Father , the question is why ?!, aren't they in the same God head , co equal , co eternal ?!... Why would an entity of such attributes asks another entity for saving him from this pain ?!.. Why would he ask and wait for any permission any way ??... He got all the power already as Son Of God ... Why ?!...

[@eie_for_you]

@@ahmedalshalchi Aaaahh, I see your conundrum! Yes, it certainly seems like a mystery, doesn't it? And this would remain a mystery if we forget another aspect of the person of Jesus Christ: his humanity. Jesus, the Son of Man (as he often called Himself in the Gospel accounts), was physically born (see the Gospel accounts of His birth), He grew up as a child no different than the rest of us, and became a man. He thirsted, was tired and weary, He suffered physical and emotional pain, and all the rest. What set Him aside from the rest of humanity is that in all of this, He never once sinned. Hebrews 4:15 "For we do not have a High Priest who cannot sympathize with our weaknesses, but was in all points tempted as we are, yet without sin." This qualified Him to become the rightful sacrifice for our sin, suffering the full penalty of our sin. As a human man, Jesus died on our behalf. God did not die, for if He did, then He would no longer be God. The humanity of Jesus died on that cross to bear the penalty for our sin. There are many places where we see the humanity of Jesus apart from His deity throughout the Gospel accounts of His life. This prayer in the garden before His sacrificial death on our account is one such example of this. As man, He was grief stricken and overwhelmed with the knowledge of the reality of what was about to happen. Here in John 17 we see the humanity of Jesus praying to His heavenly Father, God the Father. I would point you to this good website: www.gotquestions.org/humanity-of-Jesus.html In the meanwhile, we (yes, we, I have told other believers here of your questions) ... we will be praying that you will come to understand these truths.

[@ahmedalshalchi]

@@eie_for_you Mystery ?!... Why mystery ??... It is very simple and clear and unambiguous statement from Jesus that the Father is the GOD and he is just a humble servant to that GOD and asking him help so Jesus is weak and has no attributes of GOD at all !!... It seems that we may have great discussions with you Mr. Ralph and great video topic so can you please join us on this channel live streams weekly or even daily sometimes ?... in here , www.youtube.com/@HamzasDen

[@AlexejSvirid]

A women say "the Husband has no name". Another ones say "the Husband has many names". Some of women "love the Husband in all his manifestations" like: neighbour, taxi driver, coworker... But, all of those prostitutes say "the Husband is the only". Then they even talk about "trinity of the Husband" and they are not against "the Son taking the Husband's place". In the same way religious prostitutes try to hide their disgusting fornication with different gods. Furthermore, a correct pronunciation of the Name is unknown now. This is the “loyalty” of traitors! Here is the God's word spoken through Moses, Deuteronomy 11: 16-17: "Take heed to yourselves, that your heart be not deceived, and ye turn aside, and serve other gods, and worship them; And then the LORD's wrath be kindled against you, and he shut up the heaven, that there be no rain, and that the land yield not her fruit; and lest ye perish quickly from off the good land which the LORD giveth you." So, the God says there are other gods, but blind leaders of blind lead people into trap. "Jesus" means "Jehovah is salvation". This is the name of Christ real christians are hated for. "HalleluJah" means "Praze Jah" (Jehovah). Psalm 83: 18: "That men may know that thou, whose name alone is JEHOVAH, art the most high over all the earth." The problem is Devil runs the world. He is lier and murderer. This is the reason why liers feel so good while righteous people are persecuted. That's why we've got the Gospel about the God's kingdom. Jehovah would put everything in order. The dead will be resurected and we'll meet our beloved ones again! :-)