Ham Radio Basics--Jim W6LG Tests Antenna Tuners, Which One is the Most Efficient
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- čas přidán 31. 05. 2024
- Which is the most efficient antenna tuner? Jim tests the efficiency of 3 tuners. The results may surprise you.
I varied the load impedance using a homemade tuner that was not really discussed. For example, the SWR shown in the video was 1.1:1 when I calibrated the wattmeter. The SWR for the Nye Viking tuner was 1.69:1. The SWR for the Drake was 2.06:1 because the impedance was adjusted to about 25 ohms.
The homemade antenna tuner is sitting on a box with 2 wattmeters that is on top of the Nye Viking to my right in the green screen picture. The two wattmeters in one box measure the power to the two yagis so I can watch the power fed to each yagi. The homemade antenna tuner is actually two tuners in one box. That tuner is used to adjust the two yagis that are combined and fed into the Nye Viking. The red indicator lamps on the wattmeter box show which phasing line is in use. The toggle switches control vacuum relays and a series of coax connectors. Antenna switches are used to pick combinations of yagis. I don't know the overall gain of the system but it could be 9db. Through all of that 'stuff' the losses are very small. - Věda a technologie
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Regardless if you get 10k or not please keep up the videos. I really enjoy your calm, no nonsense approach. 73!
Makes perfect sense. Reactive elements within tuners have equivalent resistive losses, but these are small. Reading the comments, many people do not understand this. Energy that is reflected back to tuner is re-reflected back to antenna until energy is either consumed in feedline or transmitted out through antenna.
Outstanding video sir. You and Dave are my go to guys for any information I need especially before making purchases.
Great video, Jim. I have the same model LDG as in your video and I’m happy to hear the results of your tests. 👍
Glad I found you Jim, I'm new to this, just passed the Tech. license test. This vid is 4 years old now but wanted to comment anyway.
Thanks Jim!
I just bought a LDG tuner on the cheap, and am glad that loss is not a significant issue.
Hope you're doing well
Great video and thanks Jim from MI6GNP. 73 and keep up the great videos Sir.
Great video! Makes me think I could homebrew a decent antenna tuner.
I've always wondered, now I know. I like how you learn at the same time. It makes it real, not like it's a set up production or makes the viewer seem less intelligent
73, W9DLP
Excellent research Jim!
There was a lot going on here that wasn't specified. For example, what frequency was used? Jim's notes say the load was varied for the different tuners, but that makes comparison impossible, since it apparently was different for each tuner. Most autotuners are L-networks with switched Ls and Cs, and they will be essentially operating straight through with a 50 ohm load, and you wouldn't expect much loss. Many of the old manual tuners are essentially T-networks, so there will be losses, mostly in their inductors, even with a 50 ohm load, depending on how you tune them up (e.g. high-L & low-C vs low-L & high-C). Look at the ARRL tuner tests and they measure the losses with a range of resistive loads, which is helpful, but a lot of real-world load impedances are very reactive, which can have a HUGE impact on tuner losses, depending on the magnitude and sign of the reactance, so you can't really generalize on efficiency without a lot more specifics.
Agreed. I was going to point this out, but you already did. Also, most of the losses are dependent on your feed-line, which is where the high SWR/impedance you’ve tricked the radio into seeing as 50 ohms burns up as heat. Tuners are not the problem. Tuners at the end of long/lossy feed lines are.
I am afraid that comparing tuners under matched conditions does not give a particularly relevant picture on the losses encountered under real conditions, when a significant VSWR (say > 5) needs to be matched. After all, some (automatic) tuners may just connect input to output under matched conditions! A much more realistic picture emerges when the net transferred power (Pforward - Preflected) under seriously mismatched conditions is compared. Even then several load impedances (for example different phases of reflection coefficient) should be compared, as some tuner topologies may be better suited than others for a particular load impedance (horses for courses...). So far my criticisme. Like the video quality though and the calm way of presentinh the topic.
Nicely done Jim
Hello Jim, an interesting video, I have a question, where is the best place for the antenna tuner.
Directly at the device or better directly at the foot point of the antenna?
73 de Bernd DO1BSW
Surprising result! I'm in the market, and this is helpful! 73!
Jim just curious what do you use a tuner with if your running a monoband beam? Keep the vids coming. ..
Jim....KB8YBG
Very interesting outcome, I run a t-match via a current balun into an open wire feeder, the impedance is all over the place but I suspect the losses are low. (Nothing gets warm). I imagine that the example auto atus will only get distressed with hideous mismatches where the circulating currents start piling up. A lot of modern day hams seem to believe that every part of the transmitting chain should be 50 ohms and that atus are the devils work. In my case using an atu with a high pass characteristic helps keep the local medium wave broadcaster out of my radio. Your videos are well thought out and presented (unlike my comment), keep up the good work 73
Thanks! Makes me feel better about my budget it-100!
I was a bit surprised that you tested the first two, the big guys, at 100 w, then the autotuner at 500W. (all approximate)
Given that the tuners, at both power levels, came out looking good, it may not make a difference. But I would think that any tuner would work a bit differently at 100 vs 500 watts: Coils would heat more or less, the dielectric in non-air-spaced capacitors like the automatic units use would shift several several parameters, and things like that. I guess the surprise (I certainly was surprised too!) outcome, very high efficiency, means that there would be very little heating and other changes.
But in science a surprise is frequently a good result. Keep up the great work!
Bob Wilson, WA9D
This is a good topic. I think so because I've used an MFJ manual tuner that seems to really suppress incoming audio quite significan'tly when it's attached. In fact, I ended up taking it off my FT-450D the other night when using it up at my cabin up north. That's around their bottom of the line and perhaps intended for QRP.
Great video Jim. Thank You.
Glad you enjoyed it I will be doing more soon. 73 to you Sal, Jim
Thanks for doing this. Your videos are always clear and well done.
I am not really sure what the test circuit looks like. I suspect that the insertion losses for the tuners will be sensitive to the reactance of the load and maybe less so to operator skill (for the manual tuners). I also suspect that tuner losses will be frequency dependent. Experience with automatic tuners shows that all automatic matches are not the same; making two or more tuning attempts may produce better matches. However, even transmitting into a VSWR or 1.5:1 only produces 4% of reflected power. This rises relatively steeply to 11% at a VSWR of 20:1.
this is great video like it lot rob from Australia
Excellent video! I'd imagine the size of inductors would have more of a bearing on power handling ability; losses would increase above the rated power input figure for the tuner as the inductor saturates.
Hi Jim, thanks for this test, although I am surprised at the results. On what frequency did you do the measurements? I suspect that the low frequencies would show the most lost e.g. 1.8 MHz
Actually a very good demonstration of imaginary vs real components of impedance and power. Like the rhyme, 'twinkle, twinkle, little star, power equals "I" squared "R".' You did a great job of clearing demonstrating that the tuner isn't adding any additional 'real' resistance, and watts are the real component of complex power. Neat video.
Thanks Joshua. I am redoing that video at the request of some guys who said my test should have had a great mismatch. I have done a dry run off camera. You know, the results were about the same. The tuner lost 8 watts at 30 mhz with a 6:1SWR. The coax lost about 55% to 65% in a 100 foot length! Interesting stuff for me to test. Thanks again, Jim
interesting to watch. thanks for doing 'em
Most Losses occur in the feed-line in systems requiring a match , not the tuner. This is the entire reason remote tuners exist. You want to match your antenna to 50 ohms before it hits your feed line. Once your tuner is behind your feed-line, the feed line is now part of the antenna it’s tuning. Feed line is where the standing waves your tuner is fooling your xceiver into “not seeing” (they’re still there btw) burn up as heat. If your antenna is non-resonant, it can still be a very good radiator and quite efficient - you just have to make darn sure your feedline is either very low loss, or very short (ideally both).
Exactly. Thank you for saying it clearly. I hope to have made that point in other videos. 73, JIm W6LG
Super interesting! I've always felt my Johnson Matchbox was lower loss than any of my auto-tuners... but that may well not be the whole story! I know balanced open feedline is much less lossy at high SWR than coax. One point I think you might have made which would be useful when thinking about this... Antenna 'tuners' don't actually tune the antenna. They provide smooth transfer of power between the radio and the antenna. They're more accurately described as antenna matchers. You can still have very high SWR on your coax on the other side of an antenna tuner, and suffer lost power. Thanks for the video, and 73. de w8tam
Great and enlightening video, thanks! I wonder: Would there be a difference between "automatic" tuners and manual ones? I've always assumed that manual tuners would be better (whatever that means!), but maybe that's not true? Your results have kind of rocked my world!
Thank you for this
very helpful - thanks
Thanks Jim!
Jim - Excellent video, thanks. I also would appreciate your thoughts on locating a remote tuner at the balanced antenna feedpoint vs trying to tune at the transmitter end of the coax. Thx, and 73. Lyn, W0LEN.
Lyn Norstad if you are using a significant length of coax and the swr is significant the atu is best as close to the antenna feed point as possible. However an atu in the shack will not get invaded by spiders and bugs, or be attacked by the elements.
g0fvt , I'm using an Icom AH-4 which is well sealed against the elements. Additionally, I have it located in the attic, which helps.
Should be fine, it will be safer than my friends auto atu that he managed to bash with a lawnmower!
I recently acquired a Drake MN-2700. Have you used one and your thoughts on it. Thanks, Mark.
I have not. It may be very much the same on the inside. I absolutely love my MN2000 and will never sell it. Thanks for asking Mark. 73, Jim
i had a feeling it would be like that...keep up the videos Jim i enjoy them
73
Jeff
KE8HKX
Hi jim, got a question for you. .I am installing a new mosely tribander and my question is do I need to wrap up coax for a rf choke?? Do you have this also?? Tnx again
Yes, you need a choke at any HF antenna. You can wind the coax or use ferrite beads. Carl Mosley did not believe that the choke was needed. 73, Jim
Thanks for all you do..73s W5ZM
How about a video comparing the impedance matching range of auto antenna tuners.
Thanks Jim I learn alot from you videos.
Question been looking at the Palstar AT2K and some time getting the LA-1K 1000W.
Just wondering what you input be
KQ4CD Paul ⚓️
Very welcome Paul. Keep in touch. 73, Jim
@@ham-radio sent a email guess I did something wrong.
Used your qrz
Jim can an LDG 600 tuner be use to a FLEXradio 6000 series?
HI, I think it can. But you best asked one of Larry Youngblood's engineers. Flex has excellent customer relations. 73, Jim
Thanks for the help jim...last question. .I'm putting up a new tower this weekend. ..I have 40'..if I go 1 more section up to 50' am I going to notice a difference for the money??? Thanks for all your advice. ..Jim...KB8YBG
That depends on the topography. What is the near field ground like? Does it slope downhill, uphill, flat or what?
Well, personally, I like using tuners. I set the antenna at the antenna. Then, use the tuner to impedance match at the radio. I think SWR is king. I believe in tuners less about output, and more about smooth power delivery from the radio (less reflection) … protecting the radio finals.
I set the tuner manually using an antenna analyzer for the frequency to be used, and then switch to the radio. Always a good clean signal from me and great comments about how well I am being copied.
Hi and Thanks. I have a very different view. SWR means very little. SWR may not be an indication of resonance. The SWR can be 1:1 and the antenna is NOT resonant. Tuners do not tune antennas and do not lower reflections. I agree with protecting the finals. However, that is not necessary with a properly designed antenna system. The feedline is the king. A clean signal has little to do with SWR. Proper mic gain setting using the ALC meter and proper compression setting are very important to a clean signal. Many other things like drive, grid current, grounding, mic placement have a big impact on having a clean signal. SWR is not one of them in most situations.
Thanks for your comments. I think many have the same opinion that you do and they will agree with you. Based on my 55 years on the air, I have a different answer. If you watch the video where I do use a tuner with a high SWR at the antenna, the loss in the cable was huge. From memory, I think it was 65% loss. Thanks again & 73, Jim W6LG
Hi Jim. Yes. They key, was that you had high SWR at the antenna. And, of course, a high loss feed line does no one any good. Putting bad tires on your high-performance car never makes sense. I figured out long ago that you start at the antenna and work your way back to the radio.
Thanks for your videos and comments. Always enjoyed, appreciated, and useful.
HI Again JIm, Wow, who would have thought that there would be so little difference. One question, is it worth the cost to put a remote antenna tuner at the feed point rather than in the shack? Love you videos. Thanks, Dave VE7CMI
My guess is that if you are using coax to the tuner, it would make a significant difference. If you are using hardline or ladder line then the feedline losses are minimal. Thanks Dave and Happy New Year! 73, Jim
Jim, I really appreciate your Amateur Radio videos. Keep up the good work! 73, WA6TWJ Dave Mauldin Rough and Ready, CA. USA
Jim, while I respect your testing effort, I am a little skeptical of the results. You don't discuss - or I may have missed it - what the actual VSWR was on the antenna you were testing. If it was a 50 ohm load then the losses are most likely minimal but the "backwash" of reflected power on an antenna might show differently.
But what do I know? I'm an old former biz ad major.
You video was interesting testing the RF loss of the tuners between the tuner’s input and output. From my understanding, the most important factor in using an antenna that is not resonate is the power being reflected back to the radio, from the antenna. The antenna tuner’s job is to make the radio happy. But the reflected power from the antenna that is not resonate is coming back from the antenna to the antenna tuner. That reflected power must be absorbed by the antenna tuner and/or absorbed by the coaxial cable, instead of being radiated into the atmosphere. I heard that a remote antenna tuner is better, closer to the antenna. But if the reflected power is not going to the atmosphere, that power is being wasted, I assume as heat. If the SWR is high, the radio is happy because of the tuner, but maybe most of the power is not being radiated into the atmosphere. I don’t know if receiving signals with a non-resonate antenna has significantly reduced performance, like transmitting with a non-resonant antenna.
In fact, if the antenna tuner is at the antenna feed point, it can match the complex impedance of the antenna to the 50 ohm transmission line so there is very little loss. It's been a long time since I worked in broadcasting, so I can only remember parameters approximately, but at one station we measured the impedance of the tower with a General Radio RF bridge to be approximately 23 ohms and slightly inductive. At the base of the tower, we had a "T" matching network which matched the tower's complex impedance to 50+j0 , which is what the Heliax back to the transmitter building saw. The matching network used a coil wound with copper tubing and vacuum capacitors for low loss, and we had a ground system of 120 long radials and 120 shorter radials, very efficient. Just about all of the power delivered by the coax was radiated...
I think it's great now to have a Rigexpert antenna analyzer. Sure beats the GR RF bridge. The Rigexpert can measure 1000 points and plot a Smith chart in less than 30 seconds. Sure beats the old days sitting there adjusting the signal generator and nulling the bridge to get each point, then plotting the chart by hand...
I live right on lake erie. ..just not sure if 10' is worth the money
Great video, and I see you are using a green screen.
I watched the SWR. one had a 2 plus, another had barely a needle move. If money was plentiful at purchase time, given the low loss of power, I would have to go with the lower SWR.
Need to do the same with differing mismatched loads.
I regret to sold the KAT-500 but it was a bundle sell with the AMP. I also have LDG 3 tuners, so my conclusion is: (By the way, I had been owned ICOM AH-4/AH-2, DAIWA CNW-419, Kenwood AT-180/AT50, Palstar AT-2K, MFJ-989, MFJ-945E, etc)
KAT-500=Z-11Pro II=AH-4 > AT-200Pro II ; Manual tuner: AT-2K
KAT-500 relays running sounds very solid and it is thinner than other tuners (Z-11Pro II is thin but only 100W)
A fascinating comparison though of course the load is 50 ohms nominally. Those LP-100 sensors seem very consistent!
They do indeed. But, I have concluded that that is the way sensors function trying to capture a peak reading in a "sea" of changing values. Additionally, I think the best way (at least for me) is to look at a scope of some kind and find the peak readings. The LP-100 is a very nicely made device. I also have the one from Array Solutions. With both running, same coax line and box adjacent to each other, the values on the display are different. Back to that scope, I also found that tuning an amplifier requires advancing the load control past the peak output so that peak excursions do not "flat top". I hope that make sense. Thanks for your comments and help. I do appreciate it. 73 now from Rocklin California, Jim W6LG
Jim W6LG thank you for the reply, all understood about the amplifier too. Using X and Y inputs of a scope on input and output is another way to monitor linearity
I’m certain the efficiency is effected by the amount of mis match. Measuring the efficiency at 1:1 isn’t characteristic of the overall performance.
No kidding. Unexpected!
When you open up a can of worms and you find it's empty rejoice !
Aim a thermal thermometer inside the test tuner with the tuner's cover removed.
It would be interesting to put a 25 or 100 ohm load for 2:1 SWR, tune the tuners, then measure the outputs.
Hi Randy,
Thanks. I varied the load impedance using a homemade tuner that was not really discussed. For example, the SWR shown in the video was 1.1:1 when I calibrated the wattmeter. The SWR for the Nye Viking tuner was 1.69:1. The SWR for the Drake was 2.06:1 because the impedance was adjusted to about 25 ohms.
The homemade antenna tuner is sitting on a box with 2 wattmeters that is on top of the Nye Viking to my right in the green screen picture. The two wattmeters in one box measure the power to the two yagis so I can watch the power fed to each yagi. The homemade antenna tuner is actually two tuners in one box. That tuner is used to adjust the two yagis that are combined and fed into the Nye Viking. The red indicator lamps on the wattmeter box show which phasing line is in use. The toggle switches control vacuum relays and a series of coax connectors. Antenna switches are used to pick combinations of yagis. I don't know the overall gain of the system but it could be 9db. Through all of that 'stuff' the losses are very small.
Thanks Randy. I'll try to do one with a more extreme SWR; impedance. 73, Jim W6LG
Exactly. Tuner losses vary proportional to the load, different tuner configurations yield different results for different loads (like, T tuners do well at high impedances). I know I've seen some ARRL lab figures on this, and the tuners vary wildly in losses into different complex impedances.
a) An antenna tuner is a guy with a pair of side cutters.
b) The bigger the tuna the more pasta you'll need.
c) An impedance matching device matches your antenna impedance to your radio RF output impedance.
Absolutely! I did manufacture a device that did in fact change the physical and electrical length of the antenna using a motor. The antenna tuner that someone might buy or have in a transceiver changes nothing at the antenna. In my view, the name 'antenna tuner' is marketing baloney. Impedance Matching Device sounds better. The need to have one is overdone. Heck, I did not use one for probably 30 years. Thanks and 73, Jim
Jim W6LG lets not for get those of us who are using balanced feeders....with an eighty meter dipole and a tuner with a 4 to 1 tuner you can work jjust about anywhere with a single antenna.....
Do these devices actually tune the 'antenna' , or merely match the impedance of the radio to the tuner which takes the antenna into account? I get the impression that nothing is actually done to increase the performance of a poorly matched antenna. Isn't 'antenna tuner' a bit of a misnomer? Would 'antenna matcher' be a better name for what they do?
Yes, I agree with you. A big factor missed by many is SWR losses that can really big large. Sure the SWR is 1:1 but the real SWR can be 8:1 with a huge loss of maybe 60% depending on a bunch of factors. Thanks for pointing that out in you comments. 73, Jim W6Lg
Great review and very interesting and informative. N3SXW
Hi Jeff. Thanks for the kind and generous words. I hope to get the station finished so I can start doing videos again. 73, Jim
Sorry but I don't think you proved anything. You aren't "tuning" anything with this test method. One would need to tune a reactive load on several bands to come to a conclusion. Losses between tuners vary considerably. The ARRL Lab tested several auto tuners and manual tuners. Usually the differences were most pronounced on 160m with low impedance loads which cause more current through the coils. It is a fact that L networks have less loss than T networks. Since auto tuners use L networks they typically have lower loss than many manual tuners. The TenTec 238 series is also an L network and is very efficient compared to the T type tuners such as MFJ. 73
I concur with you, Steve
Agreed! See my post above.
73
Jim W7RY
all things are subjective, he showed best case scenario and you choose to emphasize worst case, the point being that all perspectives are valid, its what you take away from that matters..
@@rfmonkey4942 Unfortunately, there is very little to be taken away, to use your words, from these series of tests
I am surprised also... Possibly it's the toroids? In baluns, air coils are not quite as good as those wound on large toroids. Toroids will have a wider band width than air coils. But, small toroids won't hand as much power as large air coils. I think, anyway......
Fantastic video and very unexpected result. Karl, M0KRL
Not much loss, that makes sense because you don’t lose power in reactive components! Probaby just some power loss in the form of heat in the resistance in the wiring and coils.
This morning I am working on another video using a "tuner". The losses, as you already know, occurred in the coax. In fact, the losses were so great that I thought I had something really wrong in the setup. Nope. Just huge losses when the impedance at the feedpoint caused an almost infinite (if there is such a thing) SWR. Feedline losses were so great that almost no RF was at the feedpoint. I used a series of devices in parallel to get a sky high SWR. Thanks for your thoughts. 73, Jim W6LG
So, save your money and buy the inexpensive antenna toner? Is that the take away, Jim?
KE0OAP 73
Ray....or...buy an antenna like an OptiBeam for having an outstanding good swr. So you dont need a tuner at all. ;)
73s PD9Z
Good video-- dispels the "wives tale" about loss in tuners. Nothing is the answer.
Inductors and Capacitors don't consume real power (watts) right?
Because they both return the power back to the circuit:
Inductor stores energy in a Magnetic Field
Capacitor stores energy in an Electric Field
This is why Utility Companies don't like large industrial consumers that use large motors that have a lot of inductance.
Utility Companies want to maintain a power factor as close to 1 as possible.
Regular Utility Power Meters don't register Inductive or Capacitive Loads
In fact Utility Companies will actually do custom measurements of industrial client power consumption and add fees to their bills to get to an equivalent real power consumption.
Inductors and capacitors do in fact consume real power in the form of losses
Thanks. I’m interested in auto tuners. KE5TJ
KAT-500 is great.
I agree. Elecraft is the Drake of today. Built to last and built to work as advertised. Thanks for writing to me. 73, Jim W6LG
Im glad I didnt bet money on this, I woulda lost
I'm not calling them antenna tuners anymore. I now call them impedance transformers or transmatches.
@David White Because they don't actually tune antennas. All they do is match the impedance of the antenna system to that of the transceiver. They do not actually alter the radiation resistance of the antenna system.
73 VE7NDE
Enjoy your videos but the loss needs to be measured at various mismatches. Hi Z and Low Z. You are not going to show much loss if any the way you are doing it. There is a big difference in losses between tuners based on design and type of circuit when you are tuning different types of loads. As a simple test to prove this theory create a load with a low impedance mismatch of 4:1 like 12 ohms and retest and see what you get.
That is interesting Rich. What do you think, or how much do you think the average guy is trying to match? In other words, is it typically a high impedance. I think that may be the case. In the average station is there much need for a tuner that can match a say 12 ohms? Or is it a few hundred ohms that is see at the end of the feedline? What do you think? Thanks Rich for your excellent comment and suggestion. 73, Jim
Hey Jim, thanks for response. If you have Excel check out this spreadsheet. www.dj0ip.de/antenna-matchboxes/matchbox-shoot-out/ As you can see on a most the bands near 50 ohms most tuners show less than 10% loss. However some tuners will show up to 55% loss at various matches. As an example the Palstar (now Kessler) AT-AUTO which I currently own has a loss of 16 to 42% across the entire 160 meter band. On 80 meters it has less than 10% loss at most impedance's however jumps to 24% when trying to tune a 6.25 ohm match. It appears a lot of tuners do not do well with low impedance. In answer to your question, I doubt that many hams get down to 12 ohms but I am sure some (including me) do. Not uncommon to have low antennas or ground mounted verticals dip down to 25 ohms. I am guessing on auto tuners the more relays you have to engage switching in inductors and capacitors is going to add up loss. Having a good match and not switching in those components is nearly bypassing the tuner. This is just my theory and do not know that to be fact. Check out the excel sheet if you can. Anyway, not being critical and love your videos. This is just a topic that I have played around with a little.
Thanks de 4Z5UY
This test is not valid. He is testing the tuner loss with 50 ohm load. Put a 25 or 12 ohm load with reactance (like that of a short antenna) and measure the difference between in and out of tuner. I guarantee, your loss figures will be much different. Getting a watt meter that is accurate with loads not close to 50 ohm will be very hard to find. Maybe a thermocouple meter could be used.