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That's something! The problem with the average rope is stretching and degradation due to ultraviolet light. Eons ago I used the real heavy gauge, galvanized steel electric fence wire (like 12 AWG). A regular, real tower ... not such a good idea. You will see why when my next video comes out. 🙂

@@eie_for_you Polyester and nylon are sunlight resistant, especially polyester. (those pants from the '70's will never break down!) On another note, I did knowingly make some contacts while my antenna was on the ground after an ice storm and it performed rather well! Of course a matching unit was involved. They should have a contest like field day where the whole point is to have the most dysfunctional antenna that can still make contacts. Can be a lot of fun and teach about antenna physics (physics is phun)! Take care!

The funny thing is, I bought a 500 ft roll that's been unopened in my attic since 2012! The open wire works so well, I haven't bothered to replace it. Lil' Abner would be proud of my ant. :) 73!

Sometimes that is sooo true! 🙂

I can see your point, especially when made with 2x2s. I made mine with 2x4s, so that didn't end up being an issue for me. 🙂

It sure is. My first exposure to it was with a 1940 handbook! 😲

Suggestion: When using synthetic guy rope, use four to six foot of metal guy at the ground anchor point. It eliminates problems that one could have with chewing animals, minor grass fires, and string trimmer accidents.

I've never used anything but wire rope or metal wire for guy wires. I'm still a wire rope kinda guy (pun intended). For something like this with as many guys as it has on it, we are not talking very big stuff, for sure. Interesting thought about this synthetic stuff. 🙂

@@eie_for_you A friend who is a commercial tower climber introduced me to synthetic line. Apparently that's what they use on a lot of commercial broadcast tower installations these days. Ever since then that's what I have used for tower installations. The end is terminated just like a commercial wire rope would be, a eyelet type "dead end". Think of a piece of wire rope folded over to form a eyelet and then each end is twisted around like a barber pole. The inside diameter of that twisted barber pole is coated with a grit material. It is wrapped around the synthetic rope end (actually the same thing has been used with wire rope guy lines for a few decades) and that's it, no clamps needed.

@@mikesradiorepair Cool! 🙂

This a great idea you have resurrected from arrl. I wonder if a vertical wire run along the upper part would work too?

Merry Christmas to you and yours, too! 73 🙂

There sure is! You can find the download links here: nanorfe.com/nanovna-v2-software.html The basic capabilities of the nanoVNA remain the same, there is some degree of expansion to how they are used with these programs and the user interface is entirely different. Merry Christmas! 🙂

@@eie_for_you Thanks!

Thanks Vic! 73 and Merry Christmas to you and yours! 🙂

I very carefully placed electrical tape where the trace and any other copper needed to be, leaving all the rest exposed. I then etched it using Ammonium Persulfate. NOTE: This stuff likes to be *real* warm in order to work. I had to have my etching container on a heating pad (for my back) turned up to high to make it work. 🙂

You are very welcome! 🙂

It depends entirely on what you are trying to do, actually. Like receiving CW (Morse Code), you want a very narrow bandwidth so that adjacent signals do not interfere with what you are trying to receive. On the other hand, listening to an A.M. signal, you want much wider bandwidth because the signal is wider. Notice, too, that the difference is the height of the resonance, not the width of the base. 🙂

Yes, I most likely would have done it the same way you describe in you comment for this simple example. But this would not have demonstrated the whole conductances in parallel simply add together. This principle is really important when dealing with complex impedances. 🙂

The one thing that folks forget to include is the 'j'. Z=R+Xj and j*j=-1. If you do not include this in your calculations, then ... 🙂

@@eie_for_you The reason your formulas at 9:16 and 9:31 are wrong is very simple. It is known that the parallel combination of two impedances are ALWAYS less than the smaller of the two. According to your formulas the parallel resistance is GREATER than the series resistance and the parallel reactance is GREATER than the series reactance. This is not possible.

@@Jnglfvr I am now sitting here looking at my A.R.R.L. Handbook for Radio Communication, 2008 edition, page 4.45. Here on this page you will see in formulas (102) and (103) the exact same formulas that you see on the screen on my video at 9:16 and 9:31. Remember, these are used to convert the Series R+jX circuit into its parallel equivalent circuit. They are not the equations used to calculate the resulting impedance of two impedances in parallel. I hope this helps to clear this up. 🙂

@ well then I’m not sure what is meant by “equivalent parallel impedance” do you? If the impedances are different then so are the currents. So in what way, exactly, are they “equivalent?”

@@Jnglfvr If I have an impedance of, say, 3 + j8, this implies a 3 ohm resistance in series with an inductor whose reactance is 8 Ohms at a particular frequency. So, what if I want to represent this same impedance in terms of a resistance in parallel with some reactive component instead. The overall impedance would be the same. It just happens to be made up of two parallel entities instead of two series entities. These equations allow you to calculate the values of these new entities. Hope this helps. 🙂

The point of all of my videos is not just the "how to" but the "why" behind it all. I appreciate your point of view on this ... and, yes, I can see your point. However, the point of my channel is for those who want to know more, understand the why, be able to extrapolate past the "how-to" to their own application. This requires more information which I provide. 🙂

@ You certainly do 😀

@@russc788 Thanks! 🙂

I am so very glad that this was so helpful. Thank you for letting me know! 🙂

I would not apply any more than 250 mW to the input either AC (e.g. RF) or D.C.(3.5 V) 🙂

You are welcome! 🙂

Thanks, man! I'm glad this was a help! 🙂

You are very welcome! 🙂

There is nothing special about the loads for the nanoVNA except the connector (SMA). I'm assuming that you are wanting something other than SMA connector. The trick is NOT to look for "calibration standards" but to look for 50 Ohm R.F. terminations. Be mindful of the "accuracy" or they might specify this in terms of maximum SWR. Inexpensive ones will run about $30'ish. Good one's a lot more. On the other hand ... you could build your own if you are not to concerned with absolute precision. You can put 2 x 100 Ohm or 4 x 200 Ohm, 0.1%, size 1206, surface mount resistors in parallel. Then very carefully solder them into a connector being very, very careful to keep the lead lengths as short and massive as possible. Not great, but adequate for a number of applications. Hope this helps. 🙂

Thanks! And it was fun to do, too! 🙂

Really good question! The big difference between very expensive, lab quality shorts and opens and the kind that are "good enough" for our use is certain aspects of construction and calibration (measurements of delays and the like). For what we do, you can take a connector, remove its center pin and you have an open "standard." The short standard is a bit more of a challenge. I used braid (coax shield or pieces of solderwick) to make the most massive short between the center pin and the body of the connector that I could possibly make. For what the average guy does, this would work just fine. Hope this helps. 🙂

@@eie_for_you Ralph, Yes its does thanks for the explanation I do have the SMA standards for the VNA, but no N-type or PL type standards. Looking on Ebay and other places the price of lab quality standards can get pricey so making my own is my best option as of right now.

@@U812-k7j Yeah, lab quality standards are ridiculous. You could use your nanoVNA using a port extension to evaluate your resulting standards. Cal with the SMA standards, add adapters to bring you to where you can connect your homemade standards, do the port extension, then connect your standards and see how they look. As a note ... in the professional R.F. world, the SO-239 is referred to as a "UHF female" and the PL-259 is referred to as a "UHF male." Knowing this will help you find stuff on the more professional sites. 🙂

🙂

Thank you so much, man! May God bless you and your family as well. 🙂

Thanks! 🙂 As far as using the alternate form of Ro||Rp ... me, personally, it seems it might complicate it. The only way to find out is to try it out and see where it leads you. 🙂

@@eie_for_you Yes, I may actually sub it in and try it just for giggles and a new challenge. But yeah having all of those reciprocal terms all over the place will most likely make it a complete mess :)

@@BowlingSuperior Let me know how it works out. 🙂

@@eie_for_you Just tried it, first step is the Rp||Ro, this is 1/((1/Rp) + (1/Ro)), which is 1/(Ro+Rp)/(Ro*Rp), which is (Ro*Rp)/(Ro+Rp) which is just the same equation that you started with. So, yes your method was indeed the best one to start with, sweet!

@@BowlingSuperior ☺☺☺Sweet! Thanks for getting back to me! 🙂

Well, I have never used one of these. They are supposed to be for this purpose. Advertised effectiveness and actual effectiveness can be two different things, but not always. I would say to test it for yourself to determine if they do the job. 🙂

Thank you! Testing-wise, I used the default output of my VNA, 0 dBm, 1 mW. As far as maximum power handling, I'd keep it at 250 mW, 24 dBm or less. By the way, I did a quick test to 1 GHz ... it kept reasonably decent SWRs up to 800 MHz! 🙂

@eie_for_you Thank you, the reason I asked about power used for testing is that I've heard SWR measurments can, to some extent, be influenced by incident power (i.e. if the power is low and there are losses when/if the signal is reflected, the SWR will appear low). However, I don't have much practical experience, only what I read in books or saw on RUclips. So not questioning anything, just trying to get a complete picture.

@@Alex-M0OOV Gotcha! I'm not sure that incident power has any significant effect. Impedance is impedance is impedance irrespective of the power applied to it. However, impedance can change with incident power as elements heat with increased power. This might be what they are referring to(?) 🙂

@@eie_for_you I'm referring to losses in the 'transmission line'. If these losses they are high, they could be misleading and result in a low SWR (this appears to be the case for very long and lossy coax). I'm wondering if low incident power in any system can also mislead and pose a risk of showing low SWR.

@@Alex-M0OOV You are right about losses in the transmission line making the SWR at the end of the transmission line appearing lower than they really are. This effect is accentuated as you go up in frequency as the losses are greater. This is why we calibrate the measurement instrument we use to measure the SWR of the attenuator at the *end* of the transmission line where the unit to be tested will connect. This way, all of the effects of the transmission line are taken into consideration in the measurement. The only thing that shows up in the actual measurement is the unit we are testing. 🙂

B & G are susceptance and conductance associated with admittance. Admittance is the reciprocal of impedance. I explain this in my video on "Impedance Basics" (ruclips.net/video/48RNn5tXw2g/видео.html). As far as how they relate to the Smith Chart ... once you have converted your impedances to admittances, you operate the same as you do with impedances except capacitive susceptance is positive and inductive susceptance is negative. As far as a video on the subject ... it might be a little while, but I will add it to the requested videos queue. 🙂

Hola! Glad to be seen! 🙂

Thank you so much for the encouragement! 🙂

Thanks so much and you are very welcome! 🙂

Thank you! 🙂

It can be part of the overall evaluation and you do not need it to be connected to an antenna to do it. I have several videos on the subject of evaluating coax. Each of these evaluate certain aspects of a length of coax which can be compared to the datasheet for the coax to see how healthy it is. There is one on determining its characteristic impedance (ruclips.net/video/SSadMuMTlpo/видео.html), measuring its velocity factor (ruclips.net/video/dBtof6nRDj4/видео.html) and a whole series on testing coax - this is the first video in that series (ruclips.net/video/oLMdYBEnnD0/видео.html). I have a "COAX" playlist, too (ruclips.net/p/PL27hd2cDvPRs3_UpTHXF10AUM_KxeBTCn). I am hoping that this will help you. 🙂

@eie_for_you this will be of great help, I look forward to your channel.

WOW! Now that is **COOL**! 🙂

Thank you so much! 🙂

You are very welcome, my friend! 🙂

Thank you so much for the encouragement!🙂

I had to think on this for a moment or two. This is no different than measuring the characteristic impedance of a piece of coax or other transmission line. If you are looking for simple impedance, then this video would help: ruclips.net/video/SSadMuMTlpo/видео.html But it seems you are looking for complex impedance. First, measuring impedance is always S11. Second, you calibrated the VNA at the end of the port 1 cable (I am assuming) so you need to terminate the other end of the trace with your 50 Ohm termination, not port 2. The effects of the cable and so on looking into port 2 will truly mess up the readings. If you calibrated the VNA at the connector on the VNA you will have to do a "port extension" to move the reference plane for the measurement to the end of the cable right where you are connected to your trace. Note, however, *any* divergence from a 50 Ohm system when doing the port extension will render the port extension useless. See this video where I show how to do a port extension: ruclips.net/video/Pti8Erw_Kkg/видео.html I hope this helps. 🙂

@eie_for_you you r a great teacher ... Thanks

@eie_for_you Thank you... your a great teacher .... Also why cant I just measure complex impedance ( using s11 of smith chart) at required frequency and just find its magnitude ( root of sum of squares of real and imaginary).

@@minazulkhan8287 You are welcome! ... and thank you, too! What you propose is a perfectly legitimate way to do it. 🙂

Yeah, I know what you mean! There is so much to learn ... especially when it comes to R.F. stuff! I have a series/playlist on VNAs. Here is the link to the terminology video in that series in case that helps: ruclips.net/video/rRkrGE-55YA/видео.html 🙂

@@eie_for_you Thank you!

@@SarahC2 You are very welcome! 🙂

You are welcome! Be sure to also take in the video on why the extra sidebands are there. Here is the link: ruclips.net/video/LtXLhsUYqGg/видео.html 🙂

Seeing as you calibrated it at the end of the cables, the only thing that the VNA will be measuring is the Return Loss of whatever you connect the cables to. The effects of the cables have been "calibrated out" during the calibration process. 🙂

@eie_for_you Thanks... also, do port extension compensate for losses or it just compensate for phase ( in case if caliberate at ports) ?

@@minazulkhan8287 Port extensions only compensate for phase variants which effect impedance measurements. They do not help with regard to cable losses. 🙂

I have a few videos on tuning duplexers (here is the link to the first video: ruclips.net/video/ZZHknVp3asc/видео.html). So, the answer to your question is not really, but also sort of. It has the functionality but not the dynamic range. It can easily do the Return Loss portion of the tuning. But the reject frequency is where it cannot quite cut it. The reject dip will be a flat and wide bottomed dip with no way to really know what the exact reject frequency is. This is where the dynamic range issue kicks in. Part of this is due to the fact that the stimulus level is lower (mine is a fixed -9 dB!). The other part of it is the limitations of the "front end" of the receive port (port 2 - nanoVNA speak = port 1). With all of that said, it is a great way to practice tuning a duplexer! If you are willing to accept a just "OK" tune, then it might do what you want. 🙂

@@eie_for_you Thanks. I'll have to check those videos out. Have a great holiday season.

@@REKlaus And to you, too! 🙂

Yes, this procedure would work for that, too. You would just have to adjust them for the specific impedance you are looking to test (e.g. the impedance transformation PAD resistance values would change per the equations provided). 🙂