I ran across this nugget from the ARRL Antenna Handbook - "Please recognize that an antenna need not be resonant in order to be an effective radiator. There is in fact nothing magic about having a resonant antenna, provided of course that you can devise some efficient means to feed the antenna. Many amateurs use non-resonant (even random-length) antennas fed with open-wire transmission lines and antenna tuners. They radiate signals just as well as those using coaxial cable and resonant antennas, and as a bonus they usually can use these antenna systems on multiple frequency bands." -ARRL Antenna Book, Ch. 2
There is a good book that might make you rethink your understanding of what a antenna tuner is doing. Its called "Reflections" A antenna tuner is cancelling the capacitive or inductive reactance by inserting the equal reactance. If to much capacitance it inserts inductane same for to much inductance. When it does this it puts the reflected wave in phase with the original wave adding to it. Now the full power (minus any losses in the transmission line") are returned to the antenna. You need to put the SWR meter before the antenna tuner. If your using the internal antenna tuner the external meter will not read correct. This is my understanding based on the book "Reflections" by M. Walter Maxwell, W2DU. This is why Hams from years ago would use open ladder balance line because the losses are very low allowing the reflected wave to be reflected back to the antenna along with the original wave. The same could happen with good quality low loss coax. You just need to understand what the specs say for losses then add the additional losses due to the SWR. If the total is low then the power will be returned to the antenna minus those feed line losses.
The reason he put the SWR meter after the antenna tuner in this demonstration is so he could show the true SWR of the antenna system. All an "antenna tuner" does is match the impedance on the transceiver side with the impedance on the radiator side. It does not change the impedance on either side of it, which I think some hams believe to not be the case.
@@denelson83 Check out the book "Reflections" by Walter Mazwell, W2DU. It explains what an antenna turner is doing. It basically creates the same problem the antenna caused, the reason the wave is sent from the antenna back to the transmitter. By causing a similar reaction the wave is re-reflected back up to the antenna. The only losses would be in the coax as the wave goes back and forth until all of the power is at the antenna (minus coax losses). Unless the antenna and coax impedance match the transmitter there will be a mis match along the line however all the power will make it back to the antenna minus the line losses. Good reason to buy low loss coax for long runs especially above 30MHz.
Eric……Excellent Video! The Best video I ever seen on understanding tuners of all the tuner videos I watched on TH-cam. I would not have thought of connecting an external SWR/Wattmeter between the radio and antenna to compare radio meter to external meter. That really validated your point! Keep up the excellent educational videos. 73’s Mark K9ADT
I'd like to point out something. I worked on airborne radios for the air force many decades ago and a KC-135 has a probe mounted horizontally at the top of the vertical fin. Look up pictures if you want to see it. That's the HF antenna. Behind the antenna is a lightning arrester (about 18" long and weighs about 10 lbs. Behind that is the automatic antenna tuner. As close to the antenna as feasible. That way it avoids transmission line losses and I've made some pretty long distance radio checks after performing maintenance with them. On the older B-52s that I worked on, "C" and "D" models the whole upper 2/3 of the vertical fin is used as the antenna. The tuner and lightning arrester were also right there as close as feasible. So if you must use an antenna tuner it should be as close to the antenna as possible in order to avoid line losses.
True, this. I would only add that when the tuner is mounted at the antenna (which is the only valid place to put a tuner), you really can tune a wet mackerel. I've done dozens of radiotelephones on yachts (tupperware and wooden), oil tankers, oil drilling platforms, lifeboats, sailboats. The feedline (coax) ends at the tuner and the antenna begins at the tuner. Doesn't matter what you hang on the output of a tuner, it will be a radiator. Probably a bad one if it is coax cable as it might as well be buried underground for all the good it serves. A typical marine antenna is 35' with a short length of insulated neon sign insulated wire to the output of the coupler. The antenna tuners are auto-tune with presets. Phase detectors are used to check for impedance matching, and motor-drive coils, relay-selected tapped coils, and tapped toroid transformers are incuded, and pi, T, L configurations are all available and used as needed, depending on frequency. The 2kw output PA's are tuned into a 50 ohm dummy load located at the tuner and never touched again. In the old AM 2 mHz days the antenna on a boat began at the back of the RT with more of that neon sign wire. The chassis of the RT had to have wide copper straps run absolutely everywhere it could be run else you would get smoke from your mustache arcing to your mic. And then there those gorgeous 500 kHz maritime service radios. The long wire antenna ran from one end of the ship to the radio room which looked like a very comfortable office. Hopefully some of those were saved for museums.
I very much enjoyed your clever and informative video. But there are a couple of common SWR misconceptions. When you are tuning up on 160 meters, the MFJ power meter readings are quite correct and you ARE radiating most of your 50 watts! The power meter is showing the power going forward ADDED to the reflected power. Because a transmitter doesn't absorb reflected power, it re-reflects it, the reflected power ends up being added to the transmitter's power. That is why you see 105 watts Remember that your 50 watts of power has to go somewhere, either as heat in the tuner, coax, or antenna -- or it has to be radiated. If your tuner, coax, and antenna are staying cool -- most of your power is being radiated. It is a common misconception that reflected power somehow disappears -- it doesn't. Some does get wasted bouncing back and forth heating up your coax -- that is why very low loss open wire feed line is prefered for nonresonant antennas. Anyone interested in antennas and SWR needs to get a copy of "Reflections" by M. Walter Maxwell (any edition) where this is explained very well. "Reflections III" is available as a free download. ..Eugene.. AE2F
Thank you for adding this, I read it, and it cleared up a lot for me. Also there is a you tube video called Standing Up for Standing Waves that shows that the tuner does a lot more than just make the radio happy.
Radios are never "happy" just as they are never sad. The "antenna tuner" transforms the antenna system to a nominal 50 ohm load allowing the transmitter to radiate its power to the feedline and antenna.
@@timchewning8241 this means you didn't understand anything about the video! If an antenna (a dipole, for example) is not radiating fine a certain frequency waves, it will not radiate well that frequency anyhow, with or without ATU! This means that when you switch on an ATU and "tune" the ATU system, it catches the reflected power, sending it back to the antenna. Than, thsi power come back again to ATU, than again to antenna, and so on. And, making this "round trips", the power will heat the feedline and the ATU itself, bringing itself to exhaustion with the passage of time. So, the ATU is good to "move" the heat from radio final power transistors to the ATU components+feedline.
Thanks for the clear explanation. An antenna tuner might be able to tune a knitting needle, but that doesn't necessarily mean that it'll radiate efficiently.
That also means that an antenna system with an OK SWR may radiate better than one with a perfect match. Dummy loads give you a great SWR, after all. The idea of an ATU is to 1. protect your transmitter's finals and 2. let you get at least a potrion of your power output to radiate from your antenna.
Thanks for posting the video Eric.. I have an additional point for you to consider (In addition to the other comments). When making these tests with a Tuner in bypass mode, stay on the Same Band and test at 2,3, or 4 frequencies. This will give new hams an idea of what an 'swr curve' looks like. Also, in case you have not shown it before, please perform these tests using a Manual tuner. I think by learning how to use a manual tuner before going to an (outboard) auto tuner is a very valuable skill.. 73, Eric n6spp
@hamradioconcepts I know this video was about the antenna tuner, however, this is probably the BEST example of a use case for an external SWR meter. :) Thank you!
Right and tuning the antenna means shortening or lengthening the antenna itself. Pain in the butt but necessary. I cut it slightly long and then check the SWR on a range of frequencies in the desired band to determine how much to trim the antenna. Trim and try again. Usually 2 adjustments max and I'm done
And I have learned over 40+ years that the secret to broad bandwidth for a dipole is to use heavy gauge single strand pure copper wire. 8 gauge I use. Makes a huge difference!
And this is why I have made an antenna system my first acquisition toward assembling an HF ham radio station. I will be experimenting on various antenna systems to find ones that best fit what I want to do before getting the rest of the gear for my station. 73 VE7NDE
If you attach your antenna to the tuner directly or use low-loss line like ladder line you don't need a tuned antenna. The tuner will just keep reflecting any reflected energy back into the antenna until it's radiated.
Passed my Tech Exam this past Saturday. Just installed a mobile in my truck (ic-2730a). Looking next to get a mobile installed in my sons truck, and then an antenna at the house as a base. I have a lot to learn since Im new to all of this, but setting up a nice dual band antenna at home is something Im looking forward to.
I love the way you explain things. I just passed my Technician & General exams but I have no HF radio or antenna (not counting my old CB). I’m still waiting for my Call Sign. It’s delayed because of the gov shutdown! When you explain the different functions, equipment, and operations, you put some reality into it. Thank you for the time you dedicate to others.
Took tech test the beginnging of Jan. and got callsign on the 31st. Take the General in a couple of weeks. Hopefully the Government will still be open.....KJ7DKM
Napi Omaha kapi si I took both test on MLK Day and haven’t heard a word from the FCC. Glad you got yours. Let me know when you get your General and an HF radio and we’ll attempt a contact. Good luck in the future!
unfortunately his explanation is based on supposition and poor test methods. If you want to understand this stuff stop using youtube and get some good books. the Antenna book for example will show you why just about everything he says is wrong
In a previous video on the lakeshore you showed an MFJ telescopic on a grounding rod with a counterpoise wire. I eventually got one shipped to Scotland, took it to the top of a hill (we have plenty of those) and just used the tiny SWR meter on my 857 to set it's length for 20m. I forgot to raise the RF power back to 50 watts after setting the antenna length and got a 1500km contact in seconds on 5 watts. Point made.
after watching this video would it then make more sense to invest in an antenna analyzer instead, adjust the antenna for best match then use the internal antenna tuner in the radio to touch up swr on different frequencies on a specific band?
Thank you very much for this tutorial.Easily understood.The takeaway,best to get an antenna that is resonant on multiple bands.Some seasoned amateur hobbyist, are die hard believers in the antenna tuner ie automatic antenna tuners as discussed.The concept as you said only makes the match at the radio (happy radio)but does NOT tune the antennaThank you very much!.
You are misunderstanding your measuring equipment. However in order for you to understand my corrections to your presentation, I ask that you review section 3.6.7, called "Reactive Power and Power Factor" of the 2019 ARRL Handbook. Hopefully you will understand that in a reactive circuit the product of voltage and current without considering phase angle is not an accurate representation of real dissipated power. Second, please review the entire Chapter 20 entitled "Transmission Lines". Hopefully you will understand that a transmission line can be used as an impedance transforming device, in which case the currents and voltages measured (or power measured using a directional wattmeter) at certain points along the line are not an accurate representation of actual power travelling in either direction. Let me tackle this in steps. The only time a directional wattmeter or SWR bridge properly reports power in either direction is the case of a perfectly matched 50 Ohm line. In the simple case of connecting the output of your IC-7300 (without using internal antenna matching feature) to the input of a directional wattmeter (like a Bird wattmeter), and the output of the wattmeter to a 50 Ohm dummy load, the power measured in both the forward and reverse directions is accurate. You get 100% forward and 0% reflected. OK. So consider when you connect the RF output of your transmitter (again not using the internal antenna matching feature) to the input of an SWR meter or directional wattmeter, and then the output of the wattmeter to your antenna's dipole feed line, a feed line that is a close to but not a perfect match. The exact mismatch is not important for my discussion. Suppose your SWR meter measures a mismatch of 2 to 1, or maybe 4 to 1. Any reasonable value is fine for this discussion. In this situation, although the directional wattmeter inserted between the transmitter and the antenna feed line indicates that power is being returned to the source (transmitter), the exact reading is not 100% accurate. Still, for most practical purposes with a closely matched line the difference between the reported forward and reverse power measurements is accurate enough to give you a pretty good idea of the power transfer efficiency from the transmitter to the antenna, and ultimately your radiated power. And of course the important thing to realize is that because the transmitter has been designed for maximum power transfer into a 50 Ohm resistive load, it's source impedance is most probably 50 Ohms, and hence whatever power is actually flowing in the reverse direction will be completely absorbed by the transmitter (your IC-7300). Indeed, your IC-7300 contains circuitry that detects that condition and it automatically adjusts (reduces) the forward power accordingly as a precaution to prevent the reflected power from overheating the RF power output transistors. But for this discussion let's disregard that. Next, connect the RF output of your transmitter (again not using the internal antenna matching feature) to the input of a directional wattmeter, the output of the directional wattmeter to the input of an external antenna tuner, the output of the antenna tuner to the input of another directional wattmeter, and finally the output of the second directional wattmeter to the feed line of your antenna. At this point, tune the external antenna tuner so that it presents a perfect match for your transmitter. The first wattmeter will report that no power is being returned, indicating a 100% transfer of power from source to load. However, the second wattmeter will indicate very close to the same forward and reflected powers as it did before. But now there is a big difference. These measurements in the second wattmeter no long represent power flowing in either direction. The wattmeter is instead measuring reactive voltage and current, and it now incorrectly reports power flowing in both directions when in fact power really flowing only in the forward direction. It's like when measuring voltage and current in a reactive circuit. You measure reactive power, not real power. The bottom line is, that second wattmeter is fooling you. How do I know this to be true? Well, first I present the common sense argument. If you agree that no power is being reflected to the transmitter by the antenna tuner, but argue that power is being reflected to the antenna tuner by the antenna, then ask yourself where that power is going. Suppose that second wattmeter shows 80 watts forward and 20 watts reverse. If that is true, and if no power is going back to the transmitter, then it must all be going into the external antenna tuner, right? Well, what do you think 20 watts will do to that unit? It will heat it up, really hot. Since the matching circuit consists of only reactive capacitors and an inductor, that inductor would start getting really hot. But it doesn't, right? It stays cold. Of course it stays cold, and the reason is that no power is actually being reflected from the antenna back to the external antenna unit. Next I present the second, more academic and less intuitive argument. Suppose after you properly adjust your antenna you could at any time cut your antenna's feed line at any point along its length and look at the impedance in each direction. You would not see 50 Ohms resistive impedance. You would see a certain complex impedance that was the combination of some resistance and some value of reactance, either inductive or capacitive. You would see a complex impedance. Suppose as an example you happen at a particular point see a value of R + Xj in one direction. If you then looked in the other direction, you would see R - Xj. Ahah!!!! Looking in one direction you would see the complement of the impedance in the other. Suppose further that you looked at the impedance at different points along the line. You would then see different values R + Xj and R - Xj. At some points along the line it would look inductive in the direction of the antenna tuner, but capacitive in the direction of the antenna. At other points it would be the opposite. It would look capacitive in the direction of the antenna tuner and inductive in the direction of the antenna. The value of R would also vary wildly along the line. And finally, if it really were possible to cut the line at various points and look at the impedance in either direction, at every point along the line the inductive reactance in one direction would always be exactly cancelled out by an equal and opposite capacitive reactance in the other direction. And that fact is what the external antenna tuner accomplishes. That's it job! AHAHH AGAIN!!!!! This is the condition for maximum pointer transfer. That's right. At every point along the transmission line the impedance looking in the direction of the antenna tuner (the source) is the exact compliment of the impedance looking in the direction of the antenna (the load), which is the condition you learned in your basic circuit analysis course that produces maximum power transfer. Any power delivered from the source (100% of it) will flow to the load. Despite your wattmeter showing the presence of reflected power, that is only apparent. Real power flows along the line in only one direction. Many people describe this situation as the transmission line itself acting as an impedance matching transformer, with the help of the tuner of course. Again, despite what your wattmeter tells you, no power is reflected. Remember, the problem with the directional wattmeter is that it can only accurately measure power flow in a purely resistive, 50 Ohm line, a line where voltage and current are in phase. In a reactive line where voltage and current are out of phase your wattmeter responds by incorrectly reporting power in both directions. It's a similar situation to when voltage and current in a reactive circuit give you not real power, but reactive power. The bottom line is that when you use an external antenna tuner to properly match to your transmitter, the tuner does so by presenting the transmission line in the direction of the antenna a source impedance that is its complement (R +/- Xj). That is how it works! The transmission line in that situation is actually acting as an impedance transformer, and power travels along it only in one direction, from source to load. It is therefore important if you want to take maximum advantage of all the power that your rig is capable of delivering, to properly match it to your antenna. Despite great advances in the circuitry of the transmitters that we use, the same basic physics that was discovered in the 1930s is just as true today. If you want to get out, you need to match to your antenna, no matter what exact type of antenna you use, and you do that by presenting to it a source impedance that is the reactive complement of the antenna itself. Myself? I'll continue using my antenna tuner, thank you very much.
@pcastonguay: You are perfectly correct, and in the process you demonstrate that this supposed authority on TH-cam has absolutely no idea what he is talking about. Anyone can verify this by searching Wikipedia for the article called "Maximum power transfer theorem". Scroll down to the section that describes "Impedance matching in reactive circuits". The reality is, when you connect a generator having a source impedance equal to the conjugate of the impedance at the input end of a transmission line and you apply an AC signal at the resonant frequency of the lines equivalent LC circuit, you cause voltage and current to flow on the line such that real power propagates down the line from source to load. There is no reflected power. The line behaves essentially like an impedance matching device, often called an impedance matching stub. The needle of the wattmeter is reacting to apparent power, not real power. It amazes me the number of radio amateurs who don't understand this fundamental principle. I guess that is why we call them amateurs.
First off, this is in no way hate comments and as far as the video is concerned, I think is was both informative and presented well. I can clearly see that you're enthusiastic about the hobby and how much you want to share your knowledge which I can learn from with an open mind. And while I always knew early on that having an antenna cut for resonance for the band you operate is ideal, some times however, the conversion from an analog to digital representation may vary due to IC latency, partly due to using low cost components. In short, while analog meters, although difficult for some to read, for me at least, they give a better representation.
Thanks for the video. I have an R7 40-10 vertical. It is resonant at certain places, like the low end of 40. It has a very high SWR on 30. I bought a tuner to let me use the antenna more broadly without fear of harming my radio. It's opened up 30 for me, and also 6! Not as good as a dedicated 6m ant, but I can get on. 73 de N5LL
good explanation, I am working with SWR 1.2-2 and my dipole antenna is telescopic so I adjust it for the frequency I work, no balloon no tuner , getting fantastic performance
Thanks for the great explanation. Is there a benefit to getting an analog SWR/Watt meter vs a digital like that MFJ that you have right there? I was looking at getting Daiwa CN-901. Thanks.
Eric, Great video on explaining how a tuner works. From what I got from the video, it would be better to spend the money on a antenna analyzer and tune the antenna to the frequency you are going to transmit on then to spend the money on a tuner.
@@Ben-md9yx all 3 are good. I would go for the cheapest one. I have had all 3, I kept the MFJ and sold the other 2. MFJ-269 not the digital lcd 223 i believe, it eats batteries
@@HamRadioConcepts great vid. Old ham, but new to HF. Do you have a vid on making an antenna resonant to a band using the antenna analyzer? I have an Icom 7300 and an MFJ-1794 (very limited in space + HOA). My question is what tomdo with then information given to you by the antenna analyzer. Thanks!
@@HamRadioConcepts not really a valid point, as people spend $500 on an antenna analyzer for a $20 antenna. You can actually save $$ just buying a $300 tuner instead, and both time and $$ just cutting a random wire and not fussing with getting the exact length. Since the signal is reflected from the tuner back to the antenna, if you use ladder line or attach the tuner to the antenna directly, you're not really any less efficient than a resonant antenna at the end of the day.
Where antenna tuners shine are to feed Balanced feedlines for long, long runs. For instance if I lived or had a cabin in a low spot like a canyon, I could build a high impedance ladder line and go hundreds and hundreds of feet, feeding a multi-wavelength rhombic or HOHPL style antennas positioned in a much better or higher location. And remember the proof is in the pudding. Use a trusted friend to help you compare while you compare the receive. I once put up 550' of wire in a heck of an ugly loop. I got better reports on that that loop fed with the MFJ tuner than my mono-band dipoles and double bazooka style dipoles and it worked like a dream on 75. Anyway over all I agree with the video but feel at least two things were kind of brushed over or omitted, balanced feedlines and just how lossy traps and load coils can be. Don't underestimate how much loss the traps produce, which you could not easily measure at the radio. If you can afford it go and try a few different antennas and experiment and compare.
I'm just getting back into ham radio after a 40 year gap. Lots of new stuff. I enjoyed your explanation but in my old age (84) it left me a bit confused. I think you were right on but maybe didn't go far enough. (I didn't read ALL of your comments) If you use an antenna tuner and tune your random wire to 1:1 on the SWR meter at the transmitter it doesn't mean the ANY RF is being radiated. The power going through your measuring equipment is dissipated either by radiated energy (electric or magnetic?) or through HEAT. When you load up through a "tuner" you are just making your transmitter happy and you may not be radiating at all. A "Field Strength Meter) is the best way to measure since it ONLY sees radiated energy. Even then be careful where you put the FSM since radiation could just be coming from the feed line. Worth a thought?
Thanks Eric. Very good description of how antenna tuners work. You did miss one other setup that I have used in installing SSB radios on boats for many years that does work. That is a remote antenna tuner at the antenna. These work as an adjustable loading system at the antenna and work very well on all bands in its range. Similar to a screwdriver antenna they do tune the antenna to match the frequency.
Very well explained. Thank you. Can “keeping your radio happy” equal keeping your radio protected? Would that be a reason to use an auto tuner? Also, is it necessary to have a swr/watt meter when using a tuner?
Only if your antenna system is close enough to a match that the tuner can bring it the rest of the way. And having an SWR/wattmeter gives you further reassurance of actually having a matched antenna system. Besides, "keeping your radio happy" is meaningless if you cannot actually make contacts with it.
Eric, in all my years in Ham Radio your explanation of antenna Tuners is spot on. I wish had this information when starting this journey. It would have explained why I can't get hear. I appreciate your work in providing volume. A double thumbs up!!
As a part of my HF rig I'm budgeting for, I was planning on a tuner "just in case" but I guess that shouldn't be necessary. Maybe an inline SWR meter would be better money to start with?
Howdy Eric, great video on tuning a radio & antenna. I have a question/s on the antenna tuner and swr placement. Shouldn't the antenna tuner be placed between the antenna and the swr which is opposite your set up in the video? The antenna tuner is tuning the antenna on the output of the radio. Wouldn't that reflect a correct reading on your swr meter?? 73 Cliff
He's trying to show that the SWR isn't gone, the tuner is reflecting that energy back to the antenna so your radio never sees it. An SWR meter between the tuner and radio just tells you how good a job the tuner is doing keeping that reflected energy away from the radio, not that the SWR is tuned out of the antenna. If the reflected energy gets to the radio, the radio will reduce power which is why you don't want the SWR reaching it. The tuner lets the radio keep putting out full power.
Very good video about the use of antenna tunner built in to radio or external tuner. I myself have an antenna tunner only for a back up since i'm using a 80-10 meter EF half wave. The radio works fine on all the bands without the internal tuner on my Icom Ic 7300. I do use it just outside the particular bands and is a good back up if you have antenna trouble.
Truck driver for 30+ years love my th. With wideband just bought my 1 st ham a icon 5100 love you're videos will try contact from Evergreen So when licensed .I go by Melbourne a lot .
Michael Bancroft I’m a truck driver as well, only 2 years. Thinking about the same radio. What antenna do you use on your truck and how did you mount it. Right now, since I don’t have a license, I just bought a Baofeng bf f8hp just to listen and a Comet cab-790a antenna.
Thanks as a NEW ham I have a IC-7300 my landlord wont let me put any antennas on the house or in the yard Thinking about tossing a wire up in a tree I also have a MFJ VERSA TUNER V 989C 3KW ROLLER INDUCTOR TUNER Dont know if i stand a chance of contacting someone
This is really more about feed line loss. The antenna tuner DOES convert the complex impedance presented to it to 50 ohms. But coax presents a high loss if directly connected to an antenna which is not anywhere near 50 ohms at the operating frequency. The solution is to put the tuner at the feed point. AM broadcast stations have been doing this for years, which is easy to do since the operating frequency does not change. With the advent of automatic tuners, even a ham who wants a frequency-agile system can place the tuner at the feed point. I have a "stealth" 85 foot end-fed system with an MFJ-939 auto-tuner at the feed point and about 125 feet of coax back to the shack which works quite well on all bands from 80-10.
Just to be clear, the antenna tuner at the feed point both provides the loading inductance or capacitance to make the antenna resonant, as well as matching it to 50 ohms.
@David White Yes, but the feed line is mismatched if the tuner is at the transmitter end. By putting the tuner at the antenna, both the feed line and the transmitter see 50j0.
Eric, maybe a better thing to say this is the feedline between the tuner and the antenna is the problem, move the tuner next to what you are tuning then does resonate the antenna allowing your power into the tuned circuit we call an antenna. Even then an antenna needing a bunch of electronics or coils etc is still a compromised circuit. That is why the purest still advocate for dipoles or full length verticals with a huge radial or ground plane. The folks using 43 ft verticals with a tuner at the bottom have done about as well as can be done to get their power into their antenna with least coming back.
Bottom line is, the auto tuner is just keeping your transceiver happy and safe from high SWR readings and reflected power that over time can and will in most cases damage the transceiver. That’s the only reason why I use one. Radio equipment is expensive. It’s just one more item in the shack that helps promote the longevity of my equipment. By no means do I expect it to perform miracles! It’s merely a safety valve.
Nope. The 993's meter is showing what the radio sees, while the SWR meter was showing what the antenna actually is doing. When they were close, it was because the antenna was actually resonant at that frequency (or pretty close to it). The 993 simply tricks the radio into thinking the antenna can resonate the RF power, when it really can't. That reflected power is changing to heat in the 993.
I am still new to Ham/HF. Do you recommend having a secondary SWR/Watt (Such as the MFJ-849 in the video.) after the tuner in a shack setup? I have an FT-991A and was interested in adding a MFJ-929 Auto-Tuner. Do you think an auto tuner in necessary with the 991A? And would you suggest adding an additional SWR/Watt? Best Regards. 73.
I seen that also. Not cool using FM on any HF band other than the top of 10m. Should have used a CW carrier followed by his ID every time he transmitted. de WE0H ..
@@miker7962 You can use FM on HF, but the modulation factor must be 1 or less, so in a sense, it would be useless on HF, but still able to technically be done.
Anything less than at last a halfwave at the lowest band would reduce its performance on that band. The other problem would be how you feed the antenna. Coax or balance line. On bands other than the halfwave band it was cut for you will need a antenna tuner to correct the hi swr and return the signal back to the antenna. You will need low loss coax at a swr of 10:1 or open ladder line which has low losses and the tuner too.
Eric, HELP! Here is my issue I live in a 40ty ft motorhome. I can't put up a permanent hf multi band antenna. Working toward my general ticket should have it next month. Currently running a comet GP1 for 2M and 70CM for my FTM 400 XDR talk simplex and wires X works great. Getting ready to go HF can't seem to figure out the antenna looking at a yeasu ft 891 I mean what do I do here Chameleon MPAS 2.0? We drive the motorhome all over the country about 10,000 miles a year. Give it a thought drop me a suggestion thanks Mike KI5MNA
I don't completely agree with Eric about antenna tuners. Yes, an antenna tuner does not "tune" an antenna but it does transform the impedance of the radio output to the impedance of the antenna system for maximum power transfer. Take note that his MFJ meter does show lots of reflected power but, the MFJ meter is not reading the correct impedance because, the impedance from the tuner output to the antenna is NOT 50 ohms. That's why it shows a high reflected amount of power. The MFJ Power/SWR meter is showing what 50 ohms would look like if, the antenna feed line and antenna were indeed 50 ohms, but they are not. The pocket loop tuner does not change or tune the antenna, it does the same thing an antenna tuner does. It transforms the loop antenna impedance to the radio impedance for maximum power transfer. Instead of a pocket loop tuner, a regular antenna tuner capable of reaching the loop impedance does the same thing. They are both antenna tuners. They both have either capacitors, inductors or a combination of capacitors and inductors. Antenna tuner, matching network, matchbox, transmatch, antenna tuning unit (ATU), antenna coupler, and feedline coupler are all equivalent names for a device connected between a radio transmitter and its antenna, to improve power transfer between them by matching the specified load impedance of the radio to the combined input impedance of the feedline and the antenna. Tony VA7TF VE7ACF
If you're using a solid state amplifier you should always use an antenna tuner to get your match as close to 50 ohm / SWR 1:1 for the sake of protecting your finals and ensuring signal linearity. All antenna systems have tuning components; as you state 'you have to tune your 9 band resonant antenna for the area of the band you want to use. FYI, 1.4:1 isn't that special when using a SS output stage; this is why many solid state amplifier manufacturers and higher end transceivers include built in 3:1 'trimming tuners'. It might not be 'doing anything to tune your antenna' but it certainly is ensuring your PA is a clean as possible. 73, Jarrad VK3BL.
i.e., Antenna couplers. They should yield much better performance, as they allow a feedline to be terminated in its characteristic impedance at the far end.
I came from the eleven meter band and I never under stood. thanks for the information oh yes I can learn I glad there are videos out here like the I have a general license but I'm just an appliance operator
Eric, like your videos man, been licensed since 1982, been there, seen it, done it, ex-UK military sigint comms, hold/held many calls and your channel is one of the best, seriously well made. Regards F5VLY catch you on HF one day..........
Wow. Thanks for the demo. Looks like I should spend that money toward an SWR meter instead of an antenna tuner. By far the best visual representation of what so many people tried to tell me.
Hi everyone. Greetings I hope that I am at the correct page to post my question. I own a Kenwood Ts450s, and my external antenna tuner is the MFJ 993B. I am looking to buy a Interface Cable for that Radio and can't find one of as yet. Mfj5124 is the closest thing I saw but the cable end is a RJ45. What can I do. Need help Thanks.
Question: If one is using a random length wire that is greater than 1/2 wavelength in length at the transmitted frequency, but with an actual SWR that’s high, will the tuner, if placed remotely at the feed point exhibit the same characteristics as shown in this video, that is, with poor forward power? I ask this question because in the video the off resonance antenna is being fed with Coax. Thanks.
The forward power isn't affected as long as the tuner is keeping the SWR away from the radio (the radio will keep putting out full power if it sees a low SWR). The tuner reflects the reflected energy back to the antenna again, so all energy is either radiated or lost to resistance in the transmission line or antenna wire. If you put the tuner at the feed point of the antenna, there's no transmission line loss (since you're eliminating the transmission line) so almost all the energy will be radiated other than resistive losses in the antenna wire and maybe a teensy tiny bit in the tuner. If you use a low-loss transmission line like open wire line then, again, almost all energy will be radiated.
I am glad I ran across this video, as I am very interested in antennas and their tuning for some reason. I have always been suspect of tuners and how valuable they are. Having a resonant antenna has always been my goal rather than making due with a tuner, and your video makes things a bit clearer (in my favor). Thank you for sharing.
@@DJChrisArgueta only when the antenna is at resonance at the frequency you're working on . The tuner does not change the resonance of the antenna in any way .
I'm new to the HF world. So, do I need a tuner or not? I'm thinking of putting up a Hex Beam about 30 ft. high. Will I need a tuner for it or will it be a waste of time? Someone please help me here. 73's.
drew michael hi Drew it's 2E0TWG, based in England. Run a 44 foot inverted vee doublet here with 300 ohm to a remote tuner via a 4:1 Balun. Very simple set up but she works pretty well 40-10.
drew michael it's 36 feet of 300 ohm to a 4:1 Balun two feet from the ground then a 2 foot length of rg213 to the remote tuner in the low height storage shed. Then 30 feet of coax (currently rg58 being replaced by 213) to the shack. Not textbook but I've kept the coax as short as possible between Balun and tuner t minimise loss.
hi it is a great video sir i have an external automatic tuner and i want to make some measurements to make sure that it is suitable for my radio (HF transceiver ) can you please mention some test and measurements to do on my tuner to check its performance or put some reference thanks in advance
Maybe you can explain something for me. When I see you speaking to that other station, your ALC meter indicates your signal. However, on my 7300, when I'm speaking, there is NO activity on my ALC meter. Is there some 'setting' I need to look at for this?
So what about something like a G5RV Wire antenna that says it requires an antenna tuner? Obviouslly they have to make a difference on those correct? Im trying to get into HF on a budget and it seems like a G5RV is a great entry Antenna
Austin DeMarr because a G5RV is a wire only resonant in 1 or 2 bands, the rest of the bands will require a tuner to make the radio happy with a match. You cannot have a piece of wire resonant across all frequencies. It is impossible. A piece of wire is resonant ata frequency based on the length. Some people want to operate on all bands without having 10 wires all across their property, each cut for a different band. So the solution is use a tuner on 1 wire, and it will enable you to use it across different bands but does not mean it willl make the antenna resonant.
I have worked the world on 100 watts and a G5RV. Most of us do not have the room to put up multiple antennas so the G5RV is a decent compromise. The G5RV strength is that it uses low loss ladder line as the feed line which helps the antenna radiate more of the RF power. There is a reason thousands of people use it! This video isn't 100% accurate but his main point is VERY valid. A resonate antenna without a tuner in line is the best option. Using a tuner should be a compromise If you can't erect a resonate antenna. My only gripe is he is makes tuners (matchers) sound like the devil. They are not. They have their place. Commercial transmitters use them as well as the military. If I were just getting into Ham radio I would buy a resonate 20 meter antenna and then run 2 wires one for 40 and one for 75/80. I run a 80 meter windom wire and then for 40 Meters I just have a center fed dipole. Get them at least 10 feet off the ground at the ends and the middle up around 50 feet and you'll be happy. A G5RV is cheap ($50 or less) so you can't really go wrong if you have a tuner.
OK Eric, enjoy your videos. Here's my question, I have a 20 meter inverted V it performs great. I don't have a tuner connected. I can actually listen to 40 meters and it comes in VERY well, but I don't transmit. With a tuner, is it possible tune my 20 m IV to transmit on 40 meters?
Well, it is not tuning your 20m v it is providing a match to your radio so your radio thinks it’s a 40m V with a perfect SWR so your radio will be happy and output all of its power, however after the tuner it is now still going into a non efficient antenna. An antenna that is longer than the band is always better than an antenna that is too short, so an 80m antenna will be better for 40m, 20m and so on, but a 10 meter antenna will not operate correctly on anything lower than 10m (15/20/40/80) it’s way too short. So your 20m v may receive on 40 because it’s wire in the air but it will never be efficient on 40m because it’s half the size of a half wave 40m dipole
@@HamRadioConcepts OK thanks for the reply Eric, and I think that's basically what you were saying in this video. I just needed to be sure. So if I understand correctly, with my 20m inverted V, it's more likely to use a tuner to "make my radio happy", on 17,15,12 or 10 meters than 40 meters. BTW just want say, disregard the nay sayers you hear from. There are many more like myself that find you videos very informative, than those few with negative comments. I'd like to see these people make videos like this. Anyway, great job!
@@chalemi Exactly. I always used to make an 80m dipole, and I never got on 80m, but the dipole was twice as long as a 40m, 3 times longr than 20m etc, and that will give you gain, when you use your 80m dipole on 10m it is multiple wavelengths longer so that adds gain.. Tuner will be required tho.
should've watched this before getting the 993b... oh well, being that I have very limited space and lots of restrictions, all i can do is an end fed vertical, cha-250, but, being that it makes good contacts on 20 and 40 meters, and my radio thinks it's using a resonant antenna, i'll just chalk it up to getting on the air at all cost :/ great vid! 73
Good point. When you hit tune at your transmitter, you are just matching the impedance seen at your end of the transmission line to 50 ohms. However, there are many antennas that are efficient radiators, that do not present a 50 ohm load to a transmitter, hence will have a high SWR(with 50 ohm coax). Yes, using a tuner at the transceiver is a bad idea because there is much more coax loses at a high SWR then at a low SWR. When confronted with this, use remote antenna tuners, low loss coax, ladder line, Baluns etc. The loses are then just in the tuner, and the normal coax losses that occur at a low SWR. Do not discount multi band antennas that need to be tuned and lose more power in the coax. The 80 meter Carolina Windom will enable more contacts in more directions then a pair of resonate 40 and 20 meter dipoles (more omnidirectional, lower takeoff angle, plus you can work more bands). Using low loss cable makes it better, and a remote tuner makes it killer because most of the loss in the transmission line is eliminated. You can also make inefficient, poor radiating antennas that present 50 ohm loads to the transmitter too...the light bulb dummy load, loaded mobile whips, various multi band trap antennas, antennas not high enough from the ground, that give low SWR, but are not necessarily the most efficient radiators. The little loop tuner is not adjusting the antenna, it is matching the impedance of the antenna to the coax...it is a manual remote tuner, it does not make the antenna any more resonate or efficient. Keep the videos coming. Great topic.
I just have one wonder after watching this video and doing some research in this area. You were using some kind of antenna tuner which were near your device - this kind of hardware probably will not be too useful. But how about antenna tuners which are next to the antenna itself? For this example lets take multi-band antenna like MFJ-1625 (www.mfjenterprises.com/Product.php?productid=MFJ-1625) with (builtin?) manual antenna tuner next to it. I can imagine that this setup will make your antenna more or less resonant in given bands and will actually make a difference. So is there a difference between antenna tuner next to yours antenna resonant part and the one in the rig? I am just curious because I have no practical experience on HF and just wonder if it's really not useful in case of multi-band antennas like this one?
I would think if the antenna tuner was placed at the feed point of the antenna the only difference would be the losses in the coax would be less based on the additional losses the SWR adds to the spec losses of the coax from the mfg. If the losses add up to be very low then it shouldn't matter what end the tuner is located.
A lot of people tend to think a tuner is majic. Well, mostly new guys. I use one on my portable set up because my xeigu swr meter is differant than what my aa30 analyzer says... wierd. I have a question though. Where should an amp go? Before or after the tuner?
Before the tuner, because you want the unmatched higher than normal SWR to be absorbed into the tuner, this is why they make high power tuners, because you transmit that high power into the tuner.
Thanks. I build a 70 watt amp kit for my qrp portable... cant affort a real nice rig yet. And realized i wasnt sure where it went. Although 20 watts will reach across the country amd i have even gotten a dx contact, i cannot his alaska or hawaii yet. I think the amp will get me there...
Do tuners that are literally connected to the center of a dipole exist? (And I mean not through a balun) Wouldn't that be more efficient because it's transforming the 50 ohms to the impedence of the antenna directly? Edit: should have finished the video before commenting, although still curious about a remote tuner.
Very nice video! Great job.. I just wish our Ham community would stop using the misnomer of Ant Tuner, because we all know WE are the Antenna tuner with a pair of cutters or soldering gun and extra wire when the Ant is too short. For me, I would rather they stop referring to it as a “Tuner”, and instead rename it to a Antenna Matcher. I am sure you would agree.. but then again, stripes on a zebra!😝 73 and keep videos coming!
That mfj matcher that you had on your hand does that actually tune the loop antenna or just tell the radio the set is ok like the big tuner. 73's Alan in the UK
Can you please recommend a "resonant" antenna that would cover most of the bands. BTW, I cant afford some million dollar rig, but you just saved me abour 3-400 bucks on a tuner. Thanks for the video. I cant do a beam, too expensive. Retired and just got General but need antenna that would cover a lot of bands.........Thanks. Even some antenna company names?
I use a Hy-gain AV-680 9 band vertical.. Tune it for all 9 bands.. An MFJ 87-band cobweb is great too. I have videos on both of these antennas.. Also Cushcraft R-9 is identical to my Hy-gain AV680 i think... Check those out.
I think what is being seen visually on the SWR meter is only half of what is really occurring. Power reflected back is sent down the feed-line again. Then 3 things occur to that power 1 some transmits/radiates 2 some turns to heat 3 a portion is reflected again. And the cycle continues. In the end, you do not lose or reflect back as much as the power meter indicates.
The tuner only matches impedance. That is necessary for the "maximum transfer of power" That is why impedance matching is important. What does that "reflected" power do when it "comes back" to the Tuner? It gets reflected back into the wire antenna again in the "forward" direction. It still gets radiated.
I ran across this nugget from the ARRL Antenna Handbook -
"Please recognize that an antenna need not be resonant in order to be an effective radiator. There is in fact nothing magic about having a resonant antenna, provided of course that you can devise some efficient means to feed the antenna. Many amateurs use non-resonant (even random-length) antennas fed with open-wire transmission lines and antenna tuners. They radiate signals just as well as those using coaxial cable and resonant antennas, and as a bonus they usually can use these antenna systems on multiple frequency bands."
-ARRL Antenna Book, Ch. 2
There is a good book that might make you rethink your understanding of what a antenna tuner is doing. Its called "Reflections"
A antenna tuner is cancelling the capacitive or inductive reactance by inserting the equal reactance. If to much capacitance it inserts inductane same for to much inductance. When it does this it puts the reflected wave in phase with the original wave adding to it. Now the full power (minus any losses in the transmission line") are returned to the antenna.
You need to put the SWR meter before the antenna tuner. If your using the internal antenna tuner the external meter will not read correct. This is my understanding based on the book "Reflections" by M. Walter Maxwell, W2DU.
This is why Hams from years ago would use open ladder balance line because the losses are very low allowing the reflected wave to be reflected back to the antenna along with the original wave. The same could happen with good quality low loss coax. You just need to understand what the specs say for losses then add the additional losses due to the SWR. If the total is low then the power will be returned to the antenna minus those feed line losses.
Ken thanks for the tip on the reflections book that helps explain what is taught about tunnels sending the reflected power back out to the antenna.
The reason he put the SWR meter after the antenna tuner in this demonstration is so he could show the true SWR of the antenna system. All an "antenna tuner" does is match the impedance on the transceiver side with the impedance on the radiator side. It does not change the impedance on either side of it, which I think some hams believe to not be the case.
@@denelson83 Check out the book "Reflections" by Walter Mazwell, W2DU. It explains what an antenna
turner is doing. It basically creates the same problem the antenna caused, the reason the wave is sent from the antenna back to the transmitter. By causing a similar reaction the wave is re-reflected back up to the antenna. The only losses would be in the coax as the wave goes back and forth until all of the power is at the antenna (minus coax losses). Unless the antenna and coax impedance match the transmitter there will be a mis match along the line however all the power will make it back to the antenna minus the line losses. Good reason to buy low loss coax for long runs especially above 30MHz.
@@n1kkri Or use open-wire balanced feedline, such as window line or ladder line.
@@denelson83 I have been using it for years.
Eric……Excellent Video! The Best video I ever seen on understanding tuners of all the tuner videos I watched on TH-cam. I would not have thought of connecting an external SWR/Wattmeter between the radio and antenna to compare radio meter to external meter. That really validated your point! Keep up the excellent educational videos. 73’s Mark K9ADT
I'd like to point out something. I worked on airborne radios for the air force many decades ago and a KC-135 has a probe mounted horizontally at the top of the vertical fin. Look up pictures if you want to see it. That's the HF antenna. Behind the antenna is a lightning arrester (about 18" long and weighs about 10 lbs. Behind that is the automatic antenna tuner. As close to the antenna as feasible. That way it avoids transmission line losses and I've made some pretty long distance radio checks after performing maintenance with them. On the older B-52s that I worked on, "C" and "D" models the whole upper 2/3 of the vertical fin is used as the antenna. The tuner and lightning arrester were also right there as close as feasible. So if you must use an antenna tuner it should be as close to the antenna as possible in order to avoid line losses.
Chris, what frequency did this use and what was the transmission line?
Unless you are using balance feeder
True, this. I would only add that when the tuner is mounted at the antenna (which is the only valid place to put a tuner), you really can tune a wet mackerel. I've done dozens of radiotelephones on yachts (tupperware and wooden), oil tankers, oil drilling platforms, lifeboats, sailboats. The feedline (coax) ends at the tuner and the antenna begins at the tuner. Doesn't matter what you hang on the output of a tuner, it will be a radiator. Probably a bad one if it is coax cable as it might as well be buried underground for all the good it serves. A typical marine antenna is 35' with a short length of insulated neon sign insulated wire to the output of the coupler. The antenna tuners are auto-tune with presets. Phase detectors are used to check for impedance matching, and motor-drive coils, relay-selected tapped coils, and tapped toroid transformers are incuded, and pi, T, L configurations are all available and used as needed, depending on frequency. The 2kw output PA's are tuned into a 50 ohm dummy load located at the tuner and never touched again. In the old AM 2 mHz days the antenna on a boat began at the back of the RT with more of that neon sign wire. The chassis of the RT had to have wide copper straps run absolutely everywhere it could be run else you would get smoke from your mustache arcing to your mic. And then there those gorgeous 500 kHz maritime service radios. The long wire antenna ran from one end of the ship to the radio room which looked like a very comfortable office. Hopefully some of those were saved for museums.
I very much enjoyed your clever and informative video. But there are a couple of common SWR misconceptions.
When you are tuning up on 160 meters, the MFJ power meter readings are quite correct and you ARE radiating most of your 50 watts!
The power meter is showing the power going forward ADDED to the reflected power. Because a transmitter doesn't absorb reflected power, it re-reflects it, the reflected power ends up being added to the transmitter's power. That is why you see 105 watts
Remember that your 50 watts of power has to go somewhere, either as heat in the tuner, coax, or antenna -- or it has to be radiated. If your tuner, coax, and antenna are staying cool -- most of your power is being radiated. It is a common misconception that reflected power somehow disappears -- it doesn't. Some does get wasted bouncing back and forth heating up your coax -- that is why very low loss open wire feed line is prefered for nonresonant antennas.
Anyone interested in antennas and SWR needs to get a copy of "Reflections" by M. Walter Maxwell (any edition) where this is explained very well. "Reflections III" is available as a free download.
..Eugene.. AE2F
Exactly correct. Non-resonant antennas work well. Keep feedline losses low, and you're good to go. Ken WA8FCI
Thank you for adding this, I read it, and it cleared up a lot for me. Also there is a you tube video called Standing Up for Standing Waves that shows that the tuner does a lot more than just make the radio happy.
Radios are never "happy" just as they are never sad. The "antenna tuner" transforms the antenna system to a nominal 50 ohm load allowing the transmitter to radiate its power to the feedline and antenna.
@@DaDitDa "Keep feedline losses low"...
By using an open wire feed-line such as ladder line or window line, like in a doublet or a G5RV.
@@timchewning8241 this means you didn't understand anything about the video! If an antenna (a dipole, for example) is not radiating fine a certain frequency waves, it will not radiate well that frequency anyhow, with or without ATU! This means that when you switch on an ATU and "tune" the ATU system, it catches the reflected power, sending it back to the antenna. Than, thsi power come back again to ATU, than again to antenna, and so on. And, making this "round trips", the power will heat the feedline and the ATU itself, bringing itself to exhaustion with the passage of time. So, the ATU is good to "move" the heat from radio final power transistors to the ATU components+feedline.
Thanks for the clear explanation. An antenna tuner might be able to tune a knitting needle, but that doesn't necessarily mean that it'll radiate efficiently.
That also means that an antenna system with an OK SWR may radiate better than one with a perfect match. Dummy loads give you a great SWR, after all. The idea of an ATU is to 1. protect your transmitter's finals and 2. let you get at least a potrion of your power output to radiate from your antenna.
Although this video is inaccurate I respect you for not deleting the comments, 73
Thanks for posting the video Eric.. I have an additional point for you to consider (In addition to the other comments). When making these tests with a Tuner in bypass mode, stay on the Same Band and test at 2,3, or 4 frequencies. This will give new hams an idea of what an 'swr curve' looks like. Also, in case you have not shown it before, please perform these tests using a Manual tuner. I think by learning how to use a manual tuner before going to an (outboard) auto tuner is a very valuable skill.. 73, Eric n6spp
@hamradioconcepts I know this video was about the antenna tuner, however, this is probably the BEST example of a use case for an external SWR meter. :) Thank you!
For over 50 years I have been saying that a radio is no better then it's antenna. Tune the antenna first. Carl AB1ZI
Right and tuning the antenna means shortening or lengthening the antenna itself. Pain in the butt but necessary. I cut it slightly long and then check the SWR on a range of frequencies in the desired band to determine how much to trim the antenna. Trim and try again. Usually 2 adjustments max and I'm done
And I have learned over 40+ years that the secret to broad bandwidth for a dipole is to use heavy gauge single strand pure copper wire. 8 gauge I use. Makes a huge difference!
@@johninjersey And if you used something even wider? Like a copper pipe?
And this is why I have made an antenna system my first acquisition toward assembling an HF ham radio station. I will be experimenting on various antenna systems to find ones that best fit what I want to do before getting the rest of the gear for my station.
73 VE7NDE
If you attach your antenna to the tuner directly or use low-loss line like ladder line you don't need a tuned antenna. The tuner will just keep reflecting any reflected energy back into the antenna until it's radiated.
Passed my Tech Exam this past Saturday. Just installed a mobile in my truck (ic-2730a). Looking next to get a mobile installed in my sons truck, and then an antenna at the house as a base. I have a lot to learn since Im new to all of this, but setting up a nice dual band antenna at home is something Im looking forward to.
I love the way you explain things. I just passed my Technician & General exams but I have no HF radio or antenna (not counting my old CB). I’m still waiting for my Call Sign. It’s delayed because of the gov shutdown!
When you explain the different functions, equipment, and operations, you put some reality into it. Thank you for the time you dedicate to others.
Took tech test the beginnging of Jan. and got callsign on the 31st. Take the General in a couple of weeks. Hopefully the Government will still be open.....KJ7DKM
Napi Omaha kapi si I took both test on MLK Day and haven’t heard a word from the FCC. Glad you got yours. Let me know when you get your General and an HF radio and we’ll attempt a contact. Good luck in the future!
unfortunately his explanation is based on supposition and poor test methods. If you want to understand this stuff stop using youtube and get some good books. the Antenna book for example will show you why just about everything he says is wrong
In a previous video on the lakeshore you showed an MFJ telescopic on a grounding rod with a counterpoise wire. I eventually got one shipped to Scotland, took it to the top of a hill (we have plenty of those) and just used the tiny SWR meter on my 857 to set it's length for 20m. I forgot to raise the RF power back to 50 watts after setting the antenna length and got a 1500km contact in seconds on 5 watts. Point made.
This is a "Must Watch" video for new hams and even some old timers. Well done and thank you!
after watching this video would it then make more sense to invest in an antenna analyzer instead, adjust the antenna for best match then use the internal antenna tuner in the radio to touch up swr on different frequencies on a specific band?
Thank you very much for this tutorial.Easily understood.The takeaway,best to get an antenna that is resonant on multiple bands.Some seasoned amateur hobbyist, are die hard believers in the antenna tuner ie automatic antenna tuners as discussed.The concept as you said only makes the match at the radio (happy radio)but does NOT tune the antennaThank you very much!.
You are misunderstanding your measuring equipment. However in order for you to understand my corrections to your presentation, I ask that you review section 3.6.7, called "Reactive Power and Power Factor" of the 2019 ARRL Handbook. Hopefully you will understand that in a reactive circuit the product of voltage and current without considering phase angle is not an accurate representation of real dissipated power. Second, please review the entire Chapter 20 entitled "Transmission Lines". Hopefully you will understand that a transmission line can be used as an impedance transforming device, in which case the currents and voltages measured (or power measured using a directional wattmeter) at certain points along the line are not an accurate representation of actual power travelling in either direction.
Let me tackle this in steps.
The only time a directional wattmeter or SWR bridge properly reports power in either direction is the case of a perfectly matched 50 Ohm line. In the simple case of connecting the output of your IC-7300 (without using internal antenna matching feature) to the input of a directional wattmeter (like a Bird wattmeter), and the output of the wattmeter to a 50 Ohm dummy load, the power measured in both the forward and reverse directions is accurate. You get 100% forward and 0% reflected.
OK. So consider when you connect the RF output of your transmitter (again not using the internal antenna matching feature) to the input of an SWR meter or directional wattmeter, and then the output of the wattmeter to your antenna's dipole feed line, a feed line that is a close to but not a perfect match. The exact mismatch is not important for my discussion. Suppose your SWR meter measures a mismatch of 2 to 1, or maybe 4 to 1. Any reasonable value is fine for this discussion. In this situation, although the directional wattmeter inserted between the transmitter and the antenna feed line indicates that power is being returned to the source (transmitter), the exact reading is not 100% accurate. Still, for most practical purposes with a closely matched line the difference between the reported forward and reverse power measurements is accurate enough to give you a pretty good idea of the power transfer efficiency from the transmitter to the antenna, and ultimately your radiated power. And of course the important thing to realize is that because the transmitter has been designed for maximum power transfer into a 50 Ohm resistive load, it's source impedance is most probably 50 Ohms, and hence whatever power is actually flowing in the reverse direction will be completely absorbed by the transmitter (your IC-7300). Indeed, your IC-7300 contains circuitry that detects that condition and it automatically adjusts (reduces) the forward power accordingly as a precaution to prevent the reflected power from overheating the RF power output transistors. But for this discussion let's disregard that.
Next, connect the RF output of your transmitter (again not using the internal antenna matching feature) to the input of a directional wattmeter, the output of the directional wattmeter to the input of an external antenna tuner, the output of the antenna tuner to the input of another directional wattmeter, and finally the output of the second directional wattmeter to the feed line of your antenna. At this point, tune the external antenna tuner so that it presents a perfect match for your transmitter. The first wattmeter will report that no power is being returned, indicating a 100% transfer of power from source to load. However, the second wattmeter will indicate very close to the same forward and reflected powers as it did before. But now there is a big difference. These measurements in the second wattmeter no long represent power flowing in either direction. The wattmeter is instead measuring reactive voltage and current, and it now incorrectly reports power flowing in both directions when in fact power really flowing only in the forward direction. It's like when measuring voltage and current in a reactive circuit. You measure reactive power, not real power. The bottom line is, that second wattmeter is fooling you.
How do I know this to be true? Well, first I present the common sense argument. If you agree that no power is being reflected to the transmitter by the antenna tuner, but argue that power is being reflected to the antenna tuner by the antenna, then ask yourself where that power is going. Suppose that second wattmeter shows 80 watts forward and 20 watts reverse. If that is true, and if no power is going back to the transmitter, then it must all be going into the external antenna tuner, right? Well, what do you think 20 watts will do to that unit? It will heat it up, really hot. Since the matching circuit consists of only reactive capacitors and an inductor, that inductor would start getting really hot. But it doesn't, right? It stays cold. Of course it stays cold, and the reason is that no power is actually being reflected from the antenna back to the external antenna unit.
Next I present the second, more academic and less intuitive argument. Suppose after you properly adjust your antenna you could at any time cut your antenna's feed line at any point along its length and look at the impedance in each direction. You would not see 50 Ohms resistive impedance. You would see a certain complex impedance that was the combination of some resistance and some value of reactance, either inductive or capacitive. You would see a complex impedance. Suppose as an example you happen at a particular point see a value of R + Xj in one direction. If you then looked in the other direction, you would see R - Xj. Ahah!!!! Looking in one direction you would see the complement of the impedance in the other. Suppose further that you looked at the impedance at different points along the line. You would then see different values R + Xj and R - Xj. At some points along the line it would look inductive in the direction of the antenna tuner, but capacitive in the direction of the antenna. At other points it would be the opposite. It would look capacitive in the direction of the antenna tuner and inductive in the direction of the antenna. The value of R would also vary wildly along the line. And finally, if it really were possible to cut the line at various points and look at the impedance in either direction, at every point along the line the inductive reactance in one direction would always be exactly cancelled out by an equal and opposite capacitive reactance in the other direction. And that fact is what the external antenna tuner accomplishes. That's it job! AHAHH AGAIN!!!!! This is the condition for maximum pointer transfer. That's right. At every point along the transmission line the impedance looking in the direction of the antenna tuner (the source) is the exact compliment of the impedance looking in the direction of the antenna (the load), which is the condition you learned in your basic circuit analysis course that produces maximum power transfer. Any power delivered from the source (100% of it) will flow to the load. Despite your wattmeter showing the presence of reflected power, that is only apparent. Real power flows along the line in only one direction. Many people describe this situation as the transmission line itself acting as an impedance matching transformer, with the help of the tuner of course. Again, despite what your wattmeter tells you, no power is reflected. Remember, the problem with the directional wattmeter is that it can only accurately measure power flow in a purely resistive, 50 Ohm line, a line where voltage and current are in phase. In a reactive line where voltage and current are out of phase your wattmeter responds by incorrectly reporting power in both directions. It's a similar situation to when voltage and current in a reactive circuit give you not real power, but reactive power.
The bottom line is that when you use an external antenna tuner to properly match to your transmitter, the tuner does so by presenting the transmission line in the direction of the antenna a source impedance that is its complement (R +/- Xj). That is how it works! The transmission line in that situation is actually acting as an impedance transformer, and power travels along it only in one direction, from source to load. It is therefore important if you want to take maximum advantage of all the power that your rig is capable of delivering, to properly match it to your antenna.
Despite great advances in the circuitry of the transmitters that we use, the same basic physics that was discovered in the 1930s is just as true today. If you want to get out, you need to match to your antenna, no matter what exact type of antenna you use, and you do that by presenting to it a source impedance that is the reactive complement of the antenna itself. Myself? I'll continue using my antenna tuner, thank you very much.
pcastonguay: Holy smokes! Finally someone who knows what they are talking about. Great explanation.
@pcastonguay: You are perfectly correct, and in the process you demonstrate that this supposed authority on TH-cam has absolutely no idea what he is talking about. Anyone can verify this by searching Wikipedia for the article called "Maximum power transfer theorem". Scroll down to the section that describes "Impedance matching in reactive circuits". The reality is, when you connect a generator having a source impedance equal to the conjugate of the impedance at the input end of a transmission line and you apply an AC signal at the resonant frequency of the lines equivalent LC circuit, you cause voltage and current to flow on the line such that real power propagates down the line from source to load. There is no reflected power. The line behaves essentially like an impedance matching device, often called an impedance matching stub. The needle of the wattmeter is reacting to apparent power, not real power. It amazes me the number of radio amateurs who don't understand this fundamental principle. I guess that is why we call them amateurs.
I just took a screenshot of this ENTIRE write up! I’m finna go study! Thanks for sharing your knowledge, sir!
Do you do house call’s? Just asking for a friend.
Very well said!!!
First off, this is in no way hate comments and as far as the video is concerned, I think is was both informative and presented well. I can clearly see that you're enthusiastic about the hobby and how much you want to share your knowledge which I can learn from with an open mind. And while I always knew early on that having an antenna cut for resonance for the band you operate is ideal, some times however, the conversion from an analog to digital representation may vary due to IC latency, partly due to using low cost components. In short, while analog meters, although difficult for some to read, for me at least, they give a better representation.
Thanks for the video. I have an R7 40-10 vertical. It is resonant at certain places, like the low end of 40. It has a very high SWR on 30. I bought a tuner to let me use the antenna more broadly without fear of harming my radio. It's opened up 30 for me, and also 6! Not as good as a dedicated 6m ant, but I can get on. 73 de N5LL
KC2YOK
Very simple and very good this is the kind of video that makes you wanna get back into the ham.
Good job 73’s
good explanation, I am working with SWR 1.2-2 and my dipole antenna is telescopic so I adjust it for the frequency I work, no balloon no tuner , getting fantastic performance
Eric why didn't you use a field strength meter to further evaluate your theory? 🤔
Hurray hurray, Someone who understand it.
Thanks for the great explanation. Is there a benefit to getting an analog SWR/Watt meter vs a digital like that MFJ that you have right there? I was looking at getting Daiwa CN-901. Thanks.
Eric, Great video on explaining how a tuner works. From what I got from the video, it would be better to spend the money on a antenna analyzer and tune the antenna to the frequency you are going to transmit on then to spend the money on a tuner.
exactly. People buy $300 tuner for a $20 antenna.
@@HamRadioConcepts what antenna analyzer do you suggest for a first time ham? I have seen Rigexpert, MFJ and one by Comet.
@@Ben-md9yx all 3 are good. I would go for the cheapest one. I have had all 3, I kept the MFJ and sold the other 2. MFJ-269 not the digital lcd 223 i believe, it eats batteries
@@HamRadioConcepts great vid. Old ham, but new to HF. Do you have a vid on making an antenna resonant to a band using the antenna analyzer? I have an Icom 7300 and an MFJ-1794 (very limited in space + HOA). My question is what tomdo with then information given to you by the antenna analyzer. Thanks!
@@HamRadioConcepts not really a valid point, as people spend $500 on an antenna analyzer for a $20 antenna. You can actually save $$ just buying a $300 tuner instead, and both time and $$ just cutting a random wire and not fussing with getting the exact length. Since the signal is reflected from the tuner back to the antenna, if you use ladder line or attach the tuner to the antenna directly, you're not really any less efficient than a resonant antenna at the end of the day.
Where antenna tuners shine are to feed Balanced feedlines for long, long runs. For instance if I lived or had a cabin in a low spot like a canyon, I could build a high impedance ladder line and go hundreds and hundreds of feet, feeding a multi-wavelength rhombic or HOHPL style antennas positioned in a much better or higher location. And remember the proof is in the pudding. Use a trusted friend to help you compare while you compare the receive. I once put up 550' of wire in a heck of an ugly loop. I got better reports on that that loop fed with the MFJ tuner than my mono-band dipoles and double bazooka style dipoles and it worked like a dream on 75.
Anyway over all I agree with the video but feel at least two things were kind of brushed over or omitted, balanced feedlines and just how lossy traps and load coils can be. Don't underestimate how much loss the traps produce, which you could not easily measure at the radio. If you can afford it go and try a few different antennas and experiment and compare.
I'm just getting back into ham radio after a 40 year gap. Lots of new stuff. I enjoyed your explanation but in my old age (84) it left me a bit confused. I think you were right on but maybe didn't go far enough. (I didn't read ALL of your comments) If you use an antenna tuner and tune your random wire to 1:1 on the SWR meter at the transmitter it doesn't mean the ANY RF is being radiated. The power going through your measuring equipment is dissipated either by radiated energy (electric or magnetic?) or through HEAT. When you load up through a "tuner" you are just making your transmitter happy and you may not be radiating at all. A "Field Strength Meter) is the best way to measure since it ONLY sees radiated energy. Even then be careful where you put the FSM since radiation could just be coming from the feed line. Worth a thought?
Thanks Eric. Very good description of how antenna tuners work. You did miss one other setup that I have used in installing SSB radios on boats for many years that does work. That is a remote antenna tuner at the antenna. These work as an adjustable loading system at the antenna and work very well on all bands in its range. Similar to a screwdriver antenna they do tune the antenna to match the frequency.
Very well explained. Thank you. Can “keeping your radio happy” equal keeping your radio protected? Would that be a reason to use an auto tuner? Also, is it necessary to have a swr/watt meter when using a tuner?
Only if your antenna system is close enough to a match that the tuner can bring it the rest of the way. And having an SWR/wattmeter gives you further reassurance of actually having a matched antenna system. Besides, "keeping your radio happy" is meaningless if you cannot actually make contacts with it.
Hi, what kind of multi band antenna would you recommend? Thanks. Great video..
Saved me some money and frustration. New to this and really appreciate the information. Thanks.
Eric, in all my years in Ham Radio your explanation of antenna Tuners is spot on. I wish had this information when starting this journey. It would have explained why I can't get hear. I appreciate your work in providing volume. A double thumbs up!!
As a part of my HF rig I'm budgeting for, I was planning on a tuner "just in case" but I guess that shouldn't be necessary. Maybe an inline SWR meter would be better money to start with?
Howdy Eric, great video on tuning a radio & antenna. I have a question/s on the antenna tuner and swr placement. Shouldn't the antenna tuner be placed between the antenna and the swr which is opposite your set up in the video? The antenna tuner is tuning the antenna on the output of the radio. Wouldn't that reflect a correct reading on your swr meter?? 73 Cliff
He's trying to show that the SWR isn't gone, the tuner is reflecting that energy back to the antenna so your radio never sees it. An SWR meter between the tuner and radio just tells you how good a job the tuner is doing keeping that reflected energy away from the radio, not that the SWR is tuned out of the antenna. If the reflected energy gets to the radio, the radio will reduce power which is why you don't want the SWR reaching it. The tuner lets the radio keep putting out full power.
Very good video about the use of antenna tunner built in to radio or external tuner. I myself have an antenna tunner only for a back up since i'm using a 80-10 meter EF half wave. The radio works fine on all the bands without the internal tuner on my Icom Ic 7300. I do use it just outside the particular bands and is a good back up if you have antenna trouble.
Truck driver for 30+ years love my th. With wideband just bought my 1 st ham a icon 5100 love you're videos will try contact from Evergreen So when licensed .I go by Melbourne a lot .
Michael Bancroft I’m a truck driver as well, only 2 years. Thinking about the same radio. What antenna do you use on your truck and how did you mount it. Right now, since I don’t have a license, I just bought a Baofeng bf f8hp just to listen and a Comet cab-790a antenna.
I have dual fire sticks and use a comet mag mount on car .also use baofang to monitor when in wife's car
Thanks for the info. Am I better to buy an SWR meter and eliminate the antenna tuner to check antenna resonance?
Thanks as a NEW ham I have a IC-7300 my landlord wont let me put any antennas on the house or in the yard Thinking about tossing a wire up in a tree I also have a MFJ VERSA TUNER V 989C 3KW ROLLER INDUCTOR TUNER Dont know if i stand a chance of contacting someone
This is really more about feed line loss. The antenna tuner DOES convert the complex impedance presented to it to 50 ohms. But coax presents a high loss if directly connected to an antenna which is not anywhere near 50 ohms at the operating frequency. The solution is to put the tuner at the feed point. AM broadcast stations have been doing this for years, which is easy to do since the operating frequency does not change. With the advent of automatic tuners, even a ham who wants a frequency-agile system can place the tuner at the feed point.
I have a "stealth" 85 foot end-fed system with an MFJ-939 auto-tuner at the feed point and about 125 feet of coax back to the shack which works quite well on all bands from 80-10.
Just to be clear, the antenna tuner at the feed point both provides the loading inductance or capacitance to make the antenna resonant, as well as matching it to 50 ohms.
@David White Yes, but the feed line is mismatched if the tuner is at the transmitter end. By putting the tuner at the antenna, both the feed line and the transmitter see 50j0.
Eric, maybe a better thing to say this is the feedline between the tuner and the antenna is the problem, move the tuner next to what you are tuning then does resonate the antenna allowing your power into the tuned circuit we call an antenna. Even then an antenna needing a bunch of electronics or coils etc is still a compromised circuit. That is why the purest still advocate for dipoles or full length verticals with a huge radial or ground plane. The folks using 43 ft verticals with a tuner at the bottom have done about as well as can be done to get their power into their antenna with least coming back.
Did want to ask does it make any difference on a tuner that is at the antenna feed. Or is it the same results?
Great explanation of the difference between a tuned antenna and a frequency resident antenna, thanks KB9JQV.
Bottom line is, the auto tuner is just keeping your transceiver happy and safe from high SWR readings and reflected power that over time can and will in most cases damage the transceiver. That’s the only reason why I use one. Radio equipment is expensive. It’s just one more item in the shack that helps promote the longevity of my equipment. By no means do I expect it to perform miracles! It’s merely a safety valve.
Yes and no. This video is completely wrong and he has no idea what he's talking about.
Can the MFJ turner ground be connected to the Icom 7300 ground?
I mean to put a direct cable from the transmitter to the coupler?
Thank you
Thanks for this; good explanation. But why isn't the readout on the 993 matching the SWR meter? Aren't they measuring the same thing?
Nope. The 993's meter is showing what the radio sees, while the SWR meter was showing what the antenna actually is doing. When they were close, it was because the antenna was actually resonant at that frequency (or pretty close to it). The 993 simply tricks the radio into thinking the antenna can resonate the RF power, when it really can't. That reflected power is changing to heat in the 993.
Great video! Exactly the info I was looking for!
I am still new to Ham/HF. Do you recommend having a secondary SWR/Watt (Such as the MFJ-849 in the video.) after the tuner in a shack setup? I have an FT-991A and was interested in adding a MFJ-929 Auto-Tuner. Do you think an auto tuner in necessary with the 991A? And would you suggest adding an additional SWR/Watt? Best Regards. 73.
What part of 160m is for FM? 40m? 20m?
I seen that also. Not cool using FM on any HF band other than the top of 10m. Should have used a CW carrier followed by his ID every time he transmitted. de WE0H ..
@@miker7962 You can use FM on HF, but the modulation factor must be 1 or less, so in a sense, it would be useless on HF, but still able to technically be done.
Hi Eric,
The visuals make all the difference in your explanations. Great job. The best position for a tuner is right at the antenna. 73 WB3BJU
So, if you have a center fed dipole antenna, that you want to use from 10m-160m, what length would you make it, as a compromise?
Anything less than at last a halfwave at the lowest band would reduce its performance on that band. The other problem would be how you feed the antenna. Coax or balance line. On bands other than the halfwave band it was cut for you will need a antenna tuner to correct the hi swr and return the signal back to the antenna. You will need low loss coax at a swr of 10:1 or open ladder line which has low losses and the tuner too.
Eric, HELP! Here is my issue I live in a 40ty ft motorhome. I can't put up a permanent hf multi band antenna. Working toward my general ticket should have it next month. Currently running a comet GP1 for 2M and 70CM for my FTM 400 XDR talk simplex and wires X works great. Getting ready to go HF can't seem to figure out the antenna looking at a yeasu ft 891 I mean what do I do here Chameleon MPAS 2.0? We drive the motorhome all over the country about 10,000 miles a year. Give it a thought drop me a suggestion thanks Mike KI5MNA
I don't completely agree with Eric about antenna tuners. Yes, an antenna tuner does not "tune" an antenna but it does transform the impedance of the radio output to the impedance of the antenna system for maximum power transfer. Take note that his MFJ meter does show lots of reflected power but, the MFJ meter is not reading the correct impedance because, the impedance from the tuner output to the antenna is NOT 50 ohms. That's why it shows a high reflected amount of power.
The MFJ Power/SWR meter is showing what 50 ohms would look like if, the antenna feed line and antenna were indeed 50 ohms, but they are not.
The pocket loop tuner does not change or tune the antenna, it does the same thing an antenna tuner does. It transforms the loop antenna impedance to the radio impedance for maximum power transfer.
Instead of a pocket loop tuner, a regular antenna tuner capable of reaching the loop impedance does the same thing. They are both antenna tuners. They both have either capacitors, inductors or a combination of capacitors and inductors.
Antenna tuner, matching network, matchbox, transmatch, antenna tuning unit (ATU), antenna coupler, and feedline coupler are all equivalent names for a device connected between a radio transmitter and its antenna, to improve power transfer between them by matching the specified load impedance of the radio to the combined input impedance of the feedline and the antenna.
Tony
VA7TF VE7ACF
If you're using a solid state amplifier you should always use an antenna tuner to get your match as close to 50 ohm / SWR 1:1 for the sake of protecting your finals and ensuring signal linearity. All antenna systems have tuning components; as you state 'you have to tune your 9 band resonant antenna for the area of the band you want to use. FYI, 1.4:1 isn't that special when using a SS output stage; this is why many solid state amplifier manufacturers and higher end transceivers include built in 3:1 'trimming tuners'. It might not be 'doing anything to tune your antenna' but it certainly is ensuring your PA is a clean as possible. 73, Jarrad VK3BL.
Pretty sure that is exactly what he said. 👍
@@richardchandler9027 I must have missed it or felt the need to further expand on the topic, it was a long time ago so not sure which.
Excellent job. Thanks . That made sad and happy at the same time.
So what about Antenna Tuners placed between the Antenna and the Coax Cable? Right behind the Antenna..
i.e., Antenna couplers. They should yield much better performance, as they allow a feedline to be terminated in its characteristic impedance at the far end.
Superb explation
@@denelson83 - Thank You for Your Answer!
I came from the eleven meter band and I never under stood. thanks for the information oh yes I can learn I glad there are videos out here like the I have a general license but I'm just an appliance operator
This is a great video. I am a few minutes late but I found it. Thumb up and thank you.
Good detail about tuners, they only seem to protect radios not helping radiate more RF power , thanks mate
Great video. Thanks for sharing. Well explained
Eric, like your videos man, been licensed since 1982, been there, seen it, done it, ex-UK military sigint comms, hold/held many calls and your channel is one of the best, seriously well made.
Regards F5VLY catch you on HF one day..........
Thank you. This was an eye opening video
Wow. Thanks for the demo. Looks like I should spend that money toward an SWR meter instead of an antenna tuner. By far the best visual representation of what so many people tried to tell me.
Hi there. Why do you use a vhf/uhf swr watt meter on a HF radio instead of a HF swr meter. I need to know, i love to know. Thanks
That model there does HF VHF and UHF
@@HamRadioConcepts Thank you very much for answering my questions. I really appreciate it. 💯❤️👍🙏
I'm a newbie and this is a significant video.....
Thanks.
It's significantly bad
Hi everyone. Greetings I hope that I am at the correct page to post my question.
I own a Kenwood Ts450s, and my external antenna tuner is the MFJ 993B. I am looking to buy a Interface Cable for that Radio and can't find one of as yet. Mfj5124 is the closest thing I saw but the cable end is a RJ45. What can I do. Need help Thanks.
hello do you have your radios tune and aligned or are they out of the box
Question: If one is using a random length wire that is greater than 1/2 wavelength in length at the transmitted frequency, but with an actual SWR that’s high, will the tuner, if placed remotely at the feed point exhibit the same characteristics as shown in this video, that is, with poor forward power? I ask this question because in the video the off resonance antenna is being fed with Coax. Thanks.
The forward power isn't affected as long as the tuner is keeping the SWR away from the radio (the radio will keep putting out full power if it sees a low SWR). The tuner reflects the reflected energy back to the antenna again, so all energy is either radiated or lost to resistance in the transmission line or antenna wire. If you put the tuner at the feed point of the antenna, there's no transmission line loss (since you're eliminating the transmission line) so almost all the energy will be radiated other than resistive losses in the antenna wire and maybe a teensy tiny bit in the tuner. If you use a low-loss transmission line like open wire line then, again, almost all energy will be radiated.
I am glad I ran across this video, as I am very interested in antennas and their tuning for some reason. I have always been suspect of tuners and how valuable they are. Having a resonant antenna has always been my goal rather than making due with a tuner, and your video makes things a bit clearer (in my favor). Thank you for sharing.
Are antenna tuners any good for Shortwave radio,s only
Is an antenna Analyer helpful in this case?
Are you planning to test your Xiegu XG90 with the MFJ-1899T? I know you got both. Counterpoise or not, etc. Thanks.
Was always told it doesn't really TUNE anything. Its a match unit. It lets the radio see the match it needs.
Correct. The antenna matching that happens allows the radio to push max power.
@@DJChrisArgueta only when the antenna is at resonance at the frequency you're working on . The tuner does not change the resonance of the antenna in any way .
I'm new to the HF world. So, do I need a tuner or not? I'm thinking of putting up a Hex Beam about 30 ft. high. Will I need a tuner for it or will it be a waste of time? Someone please help me here. 73's.
Yes. This video is pretty much entirely wrong.
ATU with a ladderline fed doublet has minimal loss.
drew michael 100% correct. I'm amazed how many ops never consider even a short doublet over a multiband 9:1 vertical
drew michael hi Drew it's 2E0TWG, based in England. Run a 44 foot inverted vee doublet here with 300 ohm to a remote tuner via a 4:1 Balun. Very simple set up but she works pretty well 40-10.
drew michael it's 36 feet of 300 ohm to a 4:1 Balun two feet from the ground then a 2 foot length of rg213 to the remote tuner in the low height storage shed. Then 30 feet of coax (currently rg58 being replaced by 213) to the shack. Not textbook but I've kept the coax as short as possible between Balun and tuner t minimise loss.
drew michael nope as the shack is in the corner of the kitchen. Not feasible.
drew michael nothing like a g5rv. It's a doublet fed via a Balun to the tuner
hi
it is a great video sir
i have an external automatic tuner and i want to make some measurements to make sure that it is suitable for my radio (HF transceiver ) can you please mention some test and measurements to do on my tuner to check its performance or put some reference
thanks in advance
liked your video on tuners Full marks for this Eric. Thanks Rob VK2NG.
Maybe you can explain something for me. When I see you speaking to that other station, your ALC meter indicates your signal. However, on my 7300, when I'm speaking, there is NO activity on my ALC meter. Is there some 'setting' I need to look at for this?
so a tuner only makes the radio safe? so your signal still sucks going out?
So what about something like a G5RV Wire antenna that says it requires an antenna tuner? Obviouslly they have to make a difference on those correct? Im trying to get into HF on a budget and it seems like a G5RV is a great entry Antenna
Austin DeMarr because a G5RV is a wire only resonant in 1 or 2 bands, the rest of the bands will require a tuner to make the radio happy with a match. You cannot have a piece of wire resonant across all frequencies. It is impossible. A piece of wire is resonant ata frequency based on the length. Some people want to operate on all bands without having 10 wires all across their property, each cut for a different band. So the solution is use a tuner on 1 wire, and it will enable you to use it across different bands but does not mean it willl make the antenna resonant.
I have worked the world on 100 watts and a G5RV. Most of us do not have the room to put up multiple antennas so the G5RV is a decent compromise. The G5RV strength is that it uses low loss ladder line as the feed line which helps the antenna radiate more of the RF power. There is a reason thousands of people use it! This video isn't 100% accurate but his main point is VERY valid. A resonate antenna without a tuner in line is the best option. Using a tuner should be a compromise If you can't erect a resonate antenna. My only gripe is he is makes tuners (matchers) sound like the devil. They are not. They have their place. Commercial transmitters use them as well as the military. If I were just getting into Ham radio I would buy a resonate 20 meter antenna and then run 2 wires one for 40 and one for 75/80. I run a 80 meter windom wire and then for 40 Meters I just have a center fed dipole. Get them at least 10 feet off the ground at the ends and the middle up around 50 feet and you'll be happy. A G5RV is cheap ($50 or less) so you can't really go wrong if you have a tuner.
Is the antenna hooked up to the swr meter or the rig. The meter shows the true swr
Correct, thank you for the explanation.
OK Eric, enjoy your videos. Here's my question, I have a 20 meter inverted V it performs great. I don't have a tuner connected. I can actually listen to 40 meters and it comes in VERY well, but I don't transmit. With a tuner, is it possible tune my 20 m IV to transmit on 40 meters?
Well, it is not tuning your 20m v it is providing a match to your radio so your radio thinks it’s a 40m V with a perfect SWR so your radio will be happy and output all of its power, however after the tuner it is now still going into a non efficient antenna. An antenna that is longer than the band is always better than an antenna that is too short, so an 80m antenna will be better for 40m, 20m and so on, but a 10 meter antenna will not operate correctly on anything lower than 10m (15/20/40/80) it’s way too short. So your 20m v may receive on 40 because it’s wire in the air but it will never be efficient on 40m because it’s half the size of a half wave 40m dipole
@@HamRadioConcepts OK thanks for the reply Eric, and I think that's basically what you were saying in this video. I just needed to be sure. So if I understand correctly, with my 20m inverted V, it's more likely to use a tuner to "make my radio happy", on 17,15,12 or 10 meters than 40 meters.
BTW just want say, disregard the nay sayers you hear from. There are many more like myself that find you videos very informative, than those few with negative comments. I'd like to see these people make videos like this. Anyway, great job!
@@chalemi Exactly. I always used to make an 80m dipole, and I never got on 80m, but the dipole was twice as long as a 40m, 3 times longr than 20m etc, and that will give you gain, when you use your 80m dipole on 10m it is multiple wavelengths longer so that adds gain.. Tuner will be required tho.
should've watched this before getting the 993b... oh well, being that I have very limited space and lots of restrictions, all i can do is an end fed vertical, cha-250, but, being that it makes good contacts on 20 and 40 meters, and my radio thinks it's using a resonant antenna, i'll just chalk it up to getting on the air at all cost :/ great vid! 73
Good point. When you hit tune at your transmitter, you are just matching the impedance seen at your end of the transmission line to 50 ohms. However, there are many antennas that are efficient radiators, that do not present a 50 ohm load to a transmitter, hence will have a high SWR(with 50 ohm coax). Yes, using a tuner at the transceiver is a bad idea because there is much more coax loses at a high SWR then at a low SWR. When confronted with this, use remote antenna tuners, low loss coax, ladder line, Baluns etc. The loses are then just in the tuner, and the normal coax losses that occur at a low SWR. Do not discount multi band antennas that need to be tuned and lose more power in the coax. The 80 meter Carolina Windom will enable more contacts in more directions then a pair of resonate 40 and 20 meter dipoles (more omnidirectional, lower takeoff angle, plus you can work more bands). Using low loss cable makes it better, and a remote tuner makes it killer because most of the loss in the transmission line is eliminated. You can also make inefficient, poor radiating antennas that present 50 ohm loads to the transmitter too...the light bulb dummy load, loaded mobile whips, various multi band trap antennas, antennas not high enough from the ground, that give low SWR, but are not necessarily the most efficient radiators. The little loop tuner is not adjusting the antenna, it is matching the impedance of the antenna to the coax...it is a manual remote tuner, it does not make the antenna any more resonate or efficient. Keep the videos coming. Great topic.
I've got the Z100Plus with the AH-4 cable connecting it to my ICOM 718. Love it! I do wish I could do more than 30watts digital/RTTY though.
Please read arrl article , understanding swr by example.
I just have one wonder after watching this video and doing some research in this area. You were using some kind of antenna tuner which were near your device - this kind of hardware probably will not be too useful. But how about antenna tuners which are next to the antenna itself? For this example lets take multi-band antenna like MFJ-1625 (www.mfjenterprises.com/Product.php?productid=MFJ-1625) with (builtin?) manual antenna tuner next to it. I can imagine that this setup will make your antenna more or less resonant in given bands and will actually make a difference.
So is there a difference between antenna tuner next to yours antenna resonant part and the one in the rig? I am just curious because I have no practical experience on HF and just wonder if it's really not useful in case of multi-band antennas like this one?
I would think if the antenna tuner was placed at the feed point of the antenna the only difference would be the losses in the coax would be less based on the additional losses the SWR adds to the spec losses of the coax
from the mfg. If the losses add up to be very low then it shouldn't matter what end the tuner is located.
It's a RLC circuit, need to say more? Back to the basics, the theory explains it well.
A lot of people tend to think a tuner is majic. Well, mostly new guys. I use one on my portable set up because my xeigu swr meter is differant than what my aa30 analyzer says... wierd. I have a question though. Where should an amp go? Before or after the tuner?
Before the tuner, because you want the unmatched higher than normal SWR to be absorbed into the tuner, this is why they make high power tuners, because you transmit that high power into the tuner.
Thanks. I build a 70 watt amp kit for my qrp portable... cant affort a real nice rig yet. And realized i wasnt sure where it went. Although 20 watts will reach across the country amd i have even gotten a dx contact, i cannot his alaska or hawaii yet. I think the amp will get me there...
Do tuners that are literally connected to the center of a dipole exist? (And I mean not through a balun) Wouldn't that be more efficient because it's transforming the 50 ohms to the impedence of the antenna directly?
Edit: should have finished the video before commenting, although still curious about a remote tuner.
Yes. That’s called an “antenna coupler.”
@@softwarephil1709 TKS de KEØPBI
Very nice video! Great job.. I just wish our Ham community would stop using the misnomer of Ant Tuner, because we all know WE are the Antenna tuner with a pair of cutters or soldering gun and extra wire when the Ant is too short. For me, I would rather they stop referring to it as a “Tuner”, and instead rename it to a Antenna Matcher. I am sure you would agree.. but then again, stripes on a zebra!😝 73 and keep videos coming!
that a cool swr meter were can i get one what brand is that almost bought me a tuner.
Thank you for your great video.
That mfj matcher that you had on your hand does that actually tune the loop antenna or just tell the radio the set is ok like the big tuner.
73's Alan in the UK
Can you please recommend a "resonant" antenna that would cover most of the bands. BTW, I cant afford some million dollar rig, but you just saved me abour 3-400 bucks on a tuner. Thanks for the video. I cant do a beam, too expensive. Retired and just got General but need antenna that would cover a lot of bands.........Thanks. Even some antenna company names?
I use a Hy-gain AV-680 9 band vertical.. Tune it for all 9 bands.. An MFJ 87-band cobweb is great too. I have videos on both of these antennas.. Also Cushcraft R-9 is identical to my Hy-gain AV680 i think... Check those out.
@@HamRadioConcepts Thank you much, will do! 73's
Would the tuner be useful on a huge wire loop? I've heard of people hanging LONG strands of with through treea
Yes. This video is pretty much entirely wrong.
If using a random wire it is better to use ladder line or twin lead rather than coax - more efficient.
14:54 is abs.correct. tuner just tricks your rig. use an outdoor tuner if possible.
I think what is being seen visually on the SWR meter is only half of what is really occurring. Power reflected back is sent down the feed-line again. Then 3 things occur to that power 1 some transmits/radiates 2 some turns to heat 3 a portion is reflected again. And the cycle continues. In the end, you do not lose or reflect back as much as the power meter indicates.
The tuner only matches impedance. That is necessary for the "maximum transfer of power"
That is why impedance matching is important.
What does that "reflected" power do when it "comes back" to the Tuner?
It gets reflected back into the wire antenna again in the "forward"
direction. It still gets radiated.