Yeah, he made it so understandable! I was struggling for months until I seen this video. Now I feel confident enough to join the local Ham club to get more advice!! So nice to be able to understand SWL now. WRYM788 73!
I had a Sony ICF-2002 that had a simple tuner in it. It did help a little in improving reception, but did not make the antenna pick up any more stations.
Hi Kevin, Happy Holidays. Great explanation. I agree with many of the comments that antenna "tuner" creates much confusion. They should be termed antenna matching units. Stay safe. 73 WJ3U
I understand that but what about the loss in signal because of the internal electronics? I have a Yaesu frt-7700 for my frg-8800; switched off, there's a slight loss in signal when in line!
Before getting my ham license, I was a SWL'er for 60 years... in the last twelve of those I was using a Nye-Viking antenna tuner with great results on my SWL long wires. I found it very important to have the long wire as far AWAY from the QTH, gutters, roofs and any electrical noise makers to reduce the noise floor. I also used a fairly little know device, no longer made, by Palomar called the Palomar RX-100 Noise Bridge. The RX-100 and the tuner make for a great combo to "find" the "spot". Now days, I use the Palstar AT2K and with my Yaesu FTdx101MP I can suck just about any faint stray magnetic wave off the long wire and DNR and Contour it to a listenable bit of information. Thanks for this video... If I only had room for a RHOMBIC antenna farm...... now that would be something... 73 and happy holidays amigo.. Art W1SWL
Thanks a very interesting topic. The issue really is signal to noise ratio (SNR). Making the antenna resonate, either in its own right or with help of a tuner improves sensitivity to the wanted signal and hence SNR. My particular AR interest is in high SNR reception In looking at long wire, dipoles and wire antennas generally, they tend to have a large spatial extent and therefore capture a good deal of noise (unwanted, particularly local) as well as the wanted signals. Receive only antennas like active mag loops and Miniwhips with their small spatial dimensions tend to capture less noise (unwanted) and can provide significant improvements in signal to noise ratio, particularly in lower HF bands below 20m. In part this is because such antennas can be positioned in a way to minimise local noise pickup. The magloop for example can be placed low, where local E field noise is minimal but in coming H field component of wanted signals is still strong. This is the same principal behind an AM band ferrite loop stick antenna. In my own case, I use a multi band vertical and a long wire (110m) for transmission but can select separate receive only antennas. My low noise receiving antenna setup is based around an electrostatically shielded Pixel active magloop phased with a miniwhip spatially separated by about 10m. While sometimes having slightly less sensitivity, this setup has consistently lower noise, typically 20dB+ less than the vertical and wire antennas, making for much more pleasant listening. In many cases what are noisy signals when received on the vertical and wire, have almost FM quality when received on the low noise receiving antenna setup.
Around 40 years ago, after college, I used chicken wire from our 1st floor flat up to the terrace above 3rd floor, then clear across it at 1 ft above head height. Say 150 feet total, L shape. In Calcutta, India. Then via a homebrewed L tuner to our old SW valve AM radio. I would tune for least noise, easily done. Pulled in Radio Brazil, Radio Switzerland, Radio Finland etc. My best was AFRTS (armed forces radio and tv network) somewhere near the Artic circle. The simple antenna tuner made a HUGE difference, no question
One thing to consider. Detuning the system with a manual tuner can do wonders to reduce noise. This is why many hams use separate receive antennas. This gives them options. Automatic antenna tuners need a transmitted signal to work. Thus, using manual tuners for receive is the option. One can be built easily because it's not being used to transmit. Turning knobs to peak noise is quick and easy. Turning knobs to reduce noise is the same. A longwire and a manual tuner is a win for shortwave listening.
Quite right.. that is the process I use.. my location is subject to TREMENDOUS rfi.. I have something fairly nearby that covers the spectrum from 100kc to over 50 mc.. Preamp and attenuators are too coarse, but tuning the tuner for a sig/noise sweet spot has proven to be my best tool.. an outboard RF gain sorta..
Thank you for confirming my suspicions. I will soon be moving where in I will be using a vertical antenna. Knowing that verticals are especially bad about receiving noise, I am researching the possibility of adding an active receiving loop. What is the best active receiving loop on the market? Thank you! BretC/AC0AE
Lots of theory but how many times do we see, even when tuning for a transmitter, first to “tune for maximum noise” on a receiver? Proof empirical that an ATU when matched gets more signal to the receiver. Thanks for demonstrating this, Kelvin.
Agree with you 100%. I was a long time SWL'er before taking my M6 in 2010. An ATU tunes whatever antenna it is attached to near 50 ohm as possible. It tunes a range near to where you are listening to and detunes other stations outside the range, so as Tahoma says reducing unwanted noise. A great antenna to use SWLing is a rotatable loop in vertical and horizontal phases, so you can null out stronger stations and possibly pick out the weaker and DX signals. Magnetic loops are in a way like a rotatable loop with coupled ATU built in. Tuning a small section of the frequency desired and detuning anything outside the bandwidth. I found that a great antenna to use for SWLing was a long horizontal wire connected to a vertical CB antenna ( inner only ) with the matching coil removed. Slung North to South, this L shaped antenna having both polorizations and coupled with a manual ATU was excellent for a small plot, local and DX stations. Have a lovely Christmas and get some rest. I look forward to seeing some new videos in the New Year. Stay safe, 73's Andy M6APJ. Don't worry about the minorities so much, it will haggle your brain ! LOL
ATU’s absolutely help with listening as well as transmitting because they act to help tune the antenna to the receiver’s input impedance and can act as a bandpass filter to reduce interference from powerful stations transmitting on harmonically related frequencies. Is it essential? No, you can hear signals just fine without an ATU but with more noise and interference in the background.
I think you arrived at the right answer for the wrong reason. Yes, an antenna tuner can help when receiving. I have an antenna with an auto-tuner near the feed point. I can QSY and then listen. Now if I transmit a few seconds of dead carrier so the auto-tuner will do its thing, the received signals will come up a few S units. So obviously the tuner is helping reception. But why? Matching the radiation resistance is only part of the picture. I think you should also have your VNA plot the reactance of the antenna. Something many people notice is that a resonant antenna usually performs better than a non-resonant, active antenna. Why is this? It is because, at resonance, the oscillating currents in the antenna reinforce to produce stronger oscillations. In a non-resonant antenna, the oscillating currents do no reinforce, so it delivers a weaker signal. Remember that resonance is an electrical principle involving oscillating current; too often when considering antenna resonance, many people think that it has only to do with physical size. Any size antenna can be made resonant with the appropriate loading inductance or capacitance. This is one function of an antenna tuner, canceling out reactance. The other function of an antenna tuner is to match the radiation resistance of the antenna to 50 ohms. To take a little side trip, although you can make a very short antenna resonant with a large loading inductor, it will still be an inefficient antenna because it has a very low radiation resistance. Another side trip. In your setup, the antenna tuner is at the shack end of the coax. So the entire feedline is mismatched. This generates reflected power which reflects back from the antenna tuner to the antenna where it will reflect back to the tuner. With a lossy feedline, such as coax, the energy in these reflected waves is eventually burned up in the coax. Using a low loss feedline like ladder line can minimize this problem. Your auto-tuner is eliminating the reactance it sees, allowing the currents in the antenna an feedline to oscillate at the frequency the auto-tuner has tuned. This would be even more pronounced if the ATU was near the feed point so the feed line was not part of the antenna oscillation. Also it is matching the resistance it sees to the receiver input. Once again, this would be more effective if the ATU was near the feed point so the transmission line could see 50+j0 at both ends. I disagree with your premise that the antenna tuner does not change the antenna. When it cancels the antenna's reactance, it adds loading to the antenna to change its resonant frequency so that the antenna oscillates a different frequency. This is no different than adding inductance or capacitance to a tank circuit to change its resonant frequency. I propose a new term for antennas: "natural resonant frequency", the frequency at which an antenna resonates with no added loading inductance or capacitance. Because when you add capacitance or inductance to cancel reactance, you are changing the actual frequency at which the antenna currents oscillate.
I’ve been thinking about this topic quite a bit since first seeing Kevin’s interesting video. At least as of today, here’s my (another) two cents on the subject. I view the antenna system as being comprised of four components: antenna, matching network located at antenna feed point, feed line and antenna tuner (Note that I’m keeping baluns/unbaluns off the table for simplicity). As to the antenna, I think its performance will be optimal if it’s resonant for the band of interest. Given a resonant antenna and an assumed feed line impedance of 50 Ohms, the job of the matching network is to transform the antenna feed point impedance to 50 Ohms. This should result in low SWR on the line. This begs the question as to the role of the antenna tuner (in the receiver). I noted one comment in which the author suggested that the antenna tuner helps to make the entire antenna system resonant. This doesn’t seem quite right to me in that I think you want only the antenna itself to be resonant. According to (ruclips.net/video/zhsXIyq64Wc/видео.html), at least to the degree I understand it, an “antenna tuner” is used to compensate in scenarios where you are driving an antenna with frequencies off of resonance. Happy Holidays! - Jim (KK7CSC)
Your right, an antenna tuner does not make the antenna resonant, it's a transformer that let's the radio side see 50 ohms at any frequency in its range. The antenna side of that is resonant on whatever frequencies the antenna is resonant. Having the transformer (tuner) is doing nothing but transforming the impedance of the antenna on that frequency to 50 ohms, which allows more energy from the antenna to be transferred to the radio. The tuner does nothing to the impedance of the antenna on any frequency, only the physical parameters of the antenna and it's surroundings can change the resonance of the antenna.
The ATU is going to match the Antenna to the input impedance of the Tuner but we can use an 9:1 or 16:1 UNUN to couple a Longwire antenna to the radio.
Yes, assuming the longwire is medium impedance (e.g. several hundred Ohms) at the frequencies of interest, it makes sense to use a 9:1 or 16:1 unun at the antenna to reduce the impedance down to nearer 50 Ohms for connection back to the shack where it can get some final adjustment using an "ATU" to make it exactly 50 Ohms resistive presented to the receiver.
A radio receive amp is non-selective, therefore if your antenna is receiving a signal at its resonant frequency, that will engage the radio's AGC to desensitize the receive amp. When you change the resonant frequency of the antenna with an antenna tuner, the signal you want is the dominant signal, in turn stopping that other signal from desensitizing your receiver's amp. Just a dumb guess.
Excellently explained ! Couldn't be better . I am from India and learning to be a ham. This here explained a basic findamental so well. Thank you ! Could you please elbaorate more on which LDG tuner model you are using and details on yhe doublet antenna
Helpful video, Kevin. Thank you. I think much of the confusion about this subject results from the name “antenna tuner”. These devices are actually impedance matching devices, not antenna tuners. I.e., as you point out, they don’t change the actual antenna, only the coupling of it to the feed line. At least that’s the way I think about it. Meanwhile, enjoy you time off and Happy Holidays to you as well. - Jim (KK7CSC)
Antenna tuner is the correct term. It changes the antenna's resonant frequency with loading capacitance or inductance, thus tuning it to a new resonant frequency. Resonance is about oscillating currents, not necessarily about physical size. An 8 foot mobile whip can be made quarter-wave resonant, for instance, at 40 meters, by using a large loading inductor. An antenna tuner also matches the radiation resistance of the antenna to 50 ohms, much like a transformer would. Perhaps the antenna tuner is misunderstood because it is a dual function device. IMHO there needs to be a question in the General Pool about antenna tuners and antenna resonance. I think the only way to stomp out this misconception is to force amateurs to learn it right when they study for the test.
I think what you are missing is a very important point. If the tuner allows more signal into the receiver- it also allows more noise into the receiver in an equal amount. If not then you are saying that the tuner knows the difference between noise on the RX frequency and signal. an obvious impossibility. Yes, signals were louder, but so was the noise. The waterfall display color clearly shows this. This is basic S/N theory. Dale W4OP
@@loughkb So, the signal to noise does not change, then what is the tuner helping with besides making everything louder? All of today's receivers have more than enough gain to allow for low gain antennas (i.e. mismatched antennas, Beverages, Flags etc) to overcome HF noise figures.
@@loughkb Deos the tuner allow you to receive a signal that you could not receive with just the antenna? Perhaps a weaker signal than the one in the video?
@@andrewking3087 It can, when applicable, certainly make some CW contacts much easier on the ears. More signal for the filters to process. Along those lines, digital modes would be a bit better detected by demodulating and decoding software. Less dropped characters in RTTY or PSK31. A bit less snow from less AGC action in an SSTV image. And there's the additional benefit of getting the most out of the antenna across the spectrum, rather than just at it's resonant and harmonic points.
In some ways. The tuner will act as a pre-selector. Reducing nearby out of band RF that could swamp the rf pre-amp in the receiver. It will also improve the transfer of energy on the desired frequency range by creating an impedance match between the antenna and the receiver.
Hey Kevin that was a great video about the short wave and antenna tuner. I do remember that gentleman of ham radio and short wave. And I remember watching what he had to say, what are you enjoyed your video about you went into a more in-depth reason why it is good or if it’s not as good. And I really did enjoy the demonstration. How do you also hope you have a good and safe holiday enjoy the time for yourself if you don’t put out any videos before Quartzsite be safe. 73 WD5ENH Steve
I thought this was obvious. the impedance mismatch is a barrier that acts both ways and causes part of the signal energy to reflect back to where it came from. if the source of the energy is your radio (when transmitting), then you have the normal reflection of transmitted power. if the source of the signal is the antenna (when receiving) then some of the signal power reaches the radio and the rest is reflected back to the antenna, effectively reducing the power of the signal received. great content btw Kevin and your channel is one of the best out there.
It was really interesting seeing what the impedance looked like across the spectrum. I used to imagine it as a continuous slope but instead it spikes all over the place. Great vid and thanks again!
Good job. The frustrating part is its name - Antenna Tuner. As you explained it does NOT change the antenna. That element picks up RF energy more efficiently at frequencies close to or at the element's resonant length. The feedline has the same SWR - doesn't change. The Antenna Tuner changes the impedance between the feedline and the radio. There is a theorem that says something like this. Maximum energy transfer occurs when the source and load impedances are the same. The tuner does that. Doesn't matter which way the energy is flowing - transmitting or receiving - the transfer will be optimum when the impedances match. Good job! Bob - W6OPO
Good video. I have a tuner and I have done similar experiments to prove to myself that the tuner helps with receiving as well. Anyway thanks for the video and showing your VNA and receiver for the proof for all.
Interesting stuff. Is the antenna tuner you are using a passive device? I've e been playing with my antennas over the last little while. I mainly am interested in Mediumwave DX and have a couple of antennas , two flags, a delta loop and a youloop. As you described, the impedance varies with frequency. 200 to 1000 ohm on the one flag antenna, as measured with my NanoVNA at the two ends of MW. So getting a linear match across the whole MW band is impossible with just a fixed balun. Would some kind of adjustable LC circuit help? PS i like your postcard of Cape Town. My hometown. 73, Vince
If an antenna tuner to brings signal up, you have a problem with your antenna as its probably not constructed properly. If you have a good balun and coax It should not make any difference. Only on transmit is the match critical enough to make a noticeable difference.
Excellent presentation. I really like the tone of your videos and the thoroughness of the information. I do shortwave listening with an Elite 750 with a 6/10/20/40 OCFD and I've been struggling with performance. This should help.
Would a jfet preamp, with a very high input impedance, work better with whatever length of wire you are using? For receive only. It wouldn't load down the antenna and most of the signal voltage would be seen across the 1 - 10 Mohm input impedance. I did this for a direct conversion receiver I made. The preamp was a J310 jfet in a self bias config with a 10 Mohm gate resistor. The jfet fed an emitter follower. The overall gain was about unity but the input resistance was now 10 Mohms. It made it so a 2 ft telescoping antenna worked really well. Of course the long wire still worked somewhat better but the performance was very good either way. The only other issue was the preamp was also picking up 60 hz, but an appropriate choke going from the antenna to ground removed the 60 hz and didn't affect the hf.
The information presented here makes a lot of sense. I voiced a similar opinion to yours and got shouted down, so I feel vindicated that someone with your experience and knowledge makes the same points so clearly. Season's greetings to you Kevin.
The winter Solstice was big in the old pagan religions and the days around/near the solstice have been incorporated into the younger and newer religions as some form of holiday from work with the calendar rolling over 10 days post solstice.. Now, being descended from Irish and Danish ancestors my Celtic DNA prefers the old celebrations on the Solstice complete with a big feast, lots of booze, and a good orgy. So happy holidays to you also (a few months in advance)
I commend you for trying to explain the fundamentals of antenna theory. But the next video you do, please get all the facts correct, make sure all graphs and photos and drawing are correct. I am not, Not bashing you. But I am or should I say retired engineer from the broadcast industry and your talk was kind of confusing to me. I know what you were saying. But to someone who has no idea of how all this works would be totally out of phase on the subject. So good job on getting the word out there, Do your home work a little better, don't let the dog chew up all your work, lol make sure your graphs are correct. Don't try and explain a wrong drawing, make it right the first time then do a video. 73 and good luck. 👍🏻👍🏻
Nicely explained video.Yes an antenna tuner helps but there is no substitute for a good antenna in the first place.For SW listening it's been my experience to avoid antennas fed with coax.Ladder cable being the far better option.The braid on coax lets in all sorts of noises and interference which is not needed.🐻🐵☺️👍
I had no idea if a dipole and a tuner would work,but I made one anyway for my shot wave. It works, OK. I did get more channels than I did without it. I still want to find a better way to listen to my shot wave thow.
I'm just watching your video now. You're explaining a subject that most of our colleagues have some difficulty understanding: impedance. Congratulations on your presentation. It's practical and straightforward. By the way, what VNA do you use?
It's a mini VNA pro www.dxengineering.com/parts/wmo-minivnaprobt?seid=dxese1&gclid=Cj0KCQjw8--2BhCHARIsAF_w1gy2ou75jg7Sdpx0AlfTXaezEuaDTeJy0E3F8X2Yy5WY1i3I1YatkBIaAvPHEALw_wcB
I think it's for to retune the receivers preselector circuit when the antenna pulls it out of tune. For sure it helps to match the antenna, but I'm not sure if it can solve the problem completely. I have to try my Hammarlund HQ100 some day with the tuner and without it and see if there is any difference. At the moment, I have a 55m long doublet with 240ohm twin lead feedline. Cheers: OH8UBJ/Juha
The theory of reciprocity says a tuned antenna that is matched for optimal transmission must perform better on receive whilst the transmission match exists, but some ATU’s drop their tuning relays on receive thereby mismatching the antenna.
My ATU has L and C up and down buttons on the front face. Has been used successfully many times for SWL. Just play with it until signal and noise peak.
Tuning the antenna increases the signal as you showed, but also increases the noise. So the signal to noise ratio is the same, regardless of the S--meter reading. That's why beverages and receive loops work. They provide a good S/N Ratio even though they are non resonant . Sensitivity on HF modern receivers is not the problem. Their Noise Figure is way below the atmospheric noise level. So they are more than sensitive enough. The name of the game in shortwave receiving in having a good signal to noise ratio, not the highest S Meter reading. You should have mentioned that the best reason for using a tuner on HF is that it acts as a pass-band filter, reducing strong, off frequency signals which will degrade receiver dynamic range. That is more important than trying for the highest S Meter reading.
Just getting back into SWL, replaced my ancient Sangean with a sweet Tecsun PL-880, a really nice radio. I have 3 poles and 30 metres (98 ft) of wire suspended in my backyard but am learning there's more to it than throwing up a length of wire (which works amazingly well, but I'm learning that to get a quality signal some learning and fiddling is needed). I need to learn about impedance, and videos like this are great, thanks so much from Melbourne, Australia!
For SWL, is using a 1:1 BalUn (placed in-between where the antenna first connects to the Coax feed) still a good idea to help remove RFI if I'm also using an antenna tuner at the radio antenna input? Or is it redundant?
That would help to reduce common mode noise. Hashy broad RF noise that gets onto the antenna system and travels down both conductors of the feed line as if it were a single wire. It wouldn't help with any kind of carrier noise. A narrow signal generated by something.
I have an MFJ-901B antenna tuner which provides an SWR of 1. You have answered my question concerning reception. I don’t have hi tech ability to measure impedance so I must assume the impedance is good, based on the SWR. Your video is very revealing. Thank you!
For the past twenty years I've used an antenna tuner for my SWL pastime. No matter how good or bad the receiver, it always made a difference, as you amply demonstrated. Now that I'm licenced, of course I use one, as I've no wish to damage my equipment. So, good all around, in my view.
Kevin….. I see ur AT Max hat. Do you do some detecting ?? I haven’t got out in a couple years but own a Teknetics Gamma 6000. A lot of fun. Frozen tundra up here in Northeast Minnesota now. Thanks for another great video and 73. W0ZRK
Hey Kevin, ⛄ Merry Christmas & a MOST JOYOUS Yule 🎄 to you & yours! Have fun playing with your new toy, hope to see it soon. My new MGK-269D PRO should be coming in today, so I KNOW how you feel about your "toy" 😁 See you in the New Year, take care o'yourself Brother and stay WARM! L8R 🎄
Hi. QUESTION. If you have an aerial correct wavelength for the station you are listening too. If you introduce an aerial tuner does it increase the signal strength by improving the Q of the aerial. Cheers from old George.
No. The antenna is only going to 'grab' so much signal out of the air. If you're system is resonant for the frequency you are receiving, the transmatch would only introduce a small amount of loss. You may reduce the energy from other signals on different frequencies though, possibly reducing interference or desense of the RF amplifiers in the receiver.
@@loughkb Many thanks. I grew up with Thermionic Valves whereby the RF Amplifier was wideband. No band pass filters. ATU were as big as the radio. They matched impedance and also acted as band pass filters. Sometimes the knobs were marked sensitivity selectivity. The ATU increased the wanted signal by increasing the signal to noise ratio alowing the front end RF amp gain to be manually adjusted. It's rare to see an ATU as good as the old ones. Modern radios have band pass filters built in. Less knobs to adjust. Thank you for your reply it confirms my thoughts on modern ATU. Ps one of my old radios weight was 18 stone without power unit or ATU and it was only a Marconi DF Receiver ex ww2. No Transmitter. Cheers from old George just getting back into radio. 👍🤠🇬🇧
that was a great demonstration. I do a lot of short wave listing. antenna tuners some times pre selectors do help on fixed antenna. I use a MFJ analyzer to set tuner to 50 ohm. also I found a outher benefit. the tuner is aet to a frequency. everything else makes impendence go way down or up.makeing a high Q point. with strong stations or noise not in what you tuned to can over load front end of receiver. helps drop noise floor on selected frequency as well. this helps pull out weak stations. 73's
This is really interesting - Not too technically inclined, but I'd live to give this a try as I am mystified by, despite living in SE Texas, I don't get a whiff of the tropical bands between 3 and 4 MHz...FT-991a and a Cobra Senior folded doublet 140' in a somewhat inverted vee with LDG tuner, would love to see if this helps me pull out some of the smaller stations out there. Thanks & 73 de W5VOX...
more signal is one thing, but how is the SNR? also is it only impedance mismatch, or an out of resonance antenna is also attenuating? how about just using a hi-z preamp instead?
@@loughkb hmm.. not sure how can you utilize both together tbh. Tuner output is 50ohm already, so it'll be a mismatch if put before a hi-z preamp, which espects KOhms at its input. however if using the tuner after the amp, my guess it'll have no benefit as it'll be separated by preamp from the antenna, thus cannot influence the antenna by balancing out its capacitance or inductance.
Thanks for your video. Very informative. Seeing as you have a wide audience re your Christmas greeting, remember it's not winter everywhere. It's summer down here in sunny Tasmania. Merry Christmas.
A novice in radio, not even a license, this topic interested me months before I saw your video. I had heard that a tuner would not affect receiving but I thought it would, for the reason you cited. Thank you for your experiment. Great video.
Nice job, well-explained! 73, Dave, KEØOG
Yeah, he made it so understandable! I was struggling for months until I seen this video. Now I feel confident enough to join the local Ham club to get more advice!!
So nice to be able to understand SWL now.
WRYM788
73!
I had a Sony ICF-2002 that had a simple tuner in it. It did help a little in improving reception, but did not make the antenna pick up any more stations.
Agreed
For a concept best understood by physicists, you gave us a good match! Chip, NN4U
Hi Kevin,
Happy Holidays. Great explanation. I agree with many of the comments that antenna "tuner" creates much confusion. They should be termed antenna matching units. Stay safe. 73 WJ3U
It could be said whilst the tuner is adjusting the reactances to create resonance this is where the tuning name comes from ?
Used an L-match tuner for random end fed wires for many years as an SWL. Often made a significant difference.
I understand that but what about the loss in signal because of the internal electronics? I have a Yaesu frt-7700 for my frg-8800; switched off, there's a slight loss in signal when in line!
thank you for the very informative video. what hardware/software are you using to measure the impedance? thanks.
I use a BlueVNA and it's associated android app.
Merry Christmas, Kevin de YC0DMS
Before getting my ham license, I was a SWL'er for 60 years... in the last twelve of those I was using a Nye-Viking antenna tuner with great results on my SWL long wires. I found it very important to have the long wire as far AWAY from the QTH, gutters, roofs and any electrical noise makers to reduce the noise floor. I also used a fairly little know device, no longer made, by Palomar called the Palomar RX-100 Noise Bridge. The RX-100 and the tuner make for a great combo to "find" the "spot". Now days, I use the Palstar AT2K and with my Yaesu FTdx101MP I can suck just about any faint stray magnetic wave off the long wire and DNR and Contour it to a listenable bit of information. Thanks for this video... If I only had room for a RHOMBIC antenna farm...... now that would be something... 73 and happy holidays amigo.. Art W1SWL
Thanks a very interesting topic.
The issue really is signal to noise ratio (SNR). Making the antenna resonate, either in its own right or with help of a tuner improves sensitivity to the wanted signal and hence SNR.
My particular AR interest is in high SNR reception
In looking at long wire, dipoles and wire antennas generally, they tend to have a large spatial extent and therefore capture a good deal of noise (unwanted, particularly local) as well as the wanted signals.
Receive only antennas like active mag loops and Miniwhips with their small spatial dimensions tend to capture less noise (unwanted) and can provide significant improvements in signal to noise ratio, particularly in lower HF bands below 20m.
In part this is because such antennas can be positioned in a way to minimise local noise pickup. The magloop for example can be placed low, where local E field noise is minimal but in coming H field component of wanted signals is still strong. This is the same principal behind an AM band ferrite loop stick antenna.
In my own case, I use a multi band vertical and a long wire (110m) for transmission but can select separate receive only antennas.
My low noise receiving antenna setup is based around an electrostatically shielded Pixel active magloop phased with a miniwhip spatially separated by about 10m.
While sometimes having slightly less sensitivity, this setup has consistently lower noise, typically 20dB+ less than the vertical and wire antennas, making for much more pleasant listening. In many cases what are noisy signals when received on the vertical and wire, have almost FM quality when received on the low noise receiving antenna setup.
Nothing beats a video where you actually show it in action and prove the concept like that... Great job!!
Around 40 years ago, after college, I used chicken wire from our 1st floor flat up to the terrace above 3rd floor, then clear across it at 1 ft above head height. Say 150 feet total, L shape. In Calcutta, India.
Then via a homebrewed L tuner to our old SW valve AM radio. I would tune for least noise, easily done. Pulled in Radio Brazil, Radio Switzerland, Radio Finland etc. My best was AFRTS (armed forces radio and tv network) somewhere near the Artic circle.
The simple antenna tuner made a HUGE difference, no question
One thing to consider. Detuning the system with a manual tuner can do wonders to reduce noise. This is why many hams use separate receive antennas. This gives them options.
Automatic antenna tuners need a transmitted signal to work. Thus, using manual tuners for receive is the option. One can be built easily because it's not being used to transmit. Turning knobs to peak noise is quick and easy. Turning knobs to reduce noise is the same. A longwire and a manual tuner is a win for shortwave listening.
Many auto tuners (including mine from MFJ) have buttons on the front that can be used to tune manually for maximum noise.
Quite right.. that is the process I use.. my location is subject to TREMENDOUS rfi.. I have something fairly nearby that covers the spectrum from 100kc to over 50 mc..
Preamp and attenuators are too coarse, but tuning the tuner for a sig/noise sweet spot has proven to be my best tool.. an outboard RF gain sorta..
Thank you for confirming my suspicions. I will soon be moving where in I will be using a vertical antenna. Knowing that verticals are especially bad about receiving noise, I am researching the possibility of adding an active receiving loop. What is the best active receiving loop on the market? Thank you! BretC/AC0AE
Lots of theory but how many times do we see, even when tuning for a transmitter, first to “tune for maximum noise” on a receiver? Proof empirical that an ATU when matched gets more signal to the receiver. Thanks for demonstrating this, Kelvin.
That was my first thought. Tune for max signal.
Agree with you 100%. I was a long time SWL'er before taking my M6 in 2010. An ATU tunes whatever antenna it is attached to near 50 ohm as possible. It tunes a range near to where you are listening to and detunes other stations outside the range, so as Tahoma says reducing unwanted noise. A great antenna to use SWLing is a rotatable loop in vertical and horizontal phases, so you can null out stronger stations and possibly pick out the weaker and DX signals. Magnetic loops are in a way like a rotatable loop with coupled ATU built in. Tuning a small section of the frequency desired and detuning anything outside the bandwidth. I found that a great antenna to use for SWLing was a long horizontal wire connected to a vertical CB antenna ( inner only ) with the matching coil removed. Slung North to South, this L shaped antenna having both polorizations and coupled with a manual ATU was excellent for a small plot, local and DX stations. Have a lovely Christmas and get some rest. I look forward to seeing some new videos in the New Year. Stay safe, 73's Andy M6APJ. Don't worry about the minorities so much, it will haggle your brain ! LOL
Except an ATU won’t do anything for a listener because it needs a transmitter! So you’re obviously lisenced 😂
ATU’s absolutely help with listening as well as transmitting because they act to help tune the antenna to the receiver’s input impedance and can act as a bandpass filter to reduce interference from powerful stations transmitting on harmonically related frequencies. Is it essential? No, you can hear signals just fine without an ATU but with more noise and interference in the background.
I think you arrived at the right answer for the wrong reason. Yes, an antenna tuner can help when receiving. I have an antenna with an auto-tuner near the feed point. I can QSY and then listen. Now if I transmit a few seconds of dead carrier so the auto-tuner will do its thing, the received signals will come up a few S units. So obviously the tuner is helping reception. But why? Matching the radiation resistance is only part of the picture. I think you should also have your VNA plot the reactance of the antenna.
Something many people notice is that a resonant antenna usually performs better than a non-resonant, active antenna. Why is this? It is because, at resonance, the oscillating currents in the antenna reinforce to produce stronger oscillations. In a non-resonant antenna, the oscillating currents do no reinforce, so it delivers a weaker signal. Remember that resonance is an electrical principle involving oscillating current; too often when considering antenna resonance, many people think that it has only to do with physical size. Any size antenna can be made resonant with the appropriate loading inductance or capacitance. This is one function of an antenna tuner, canceling out reactance. The other function of an antenna tuner is to match the radiation resistance of the antenna to 50 ohms.
To take a little side trip, although you can make a very short antenna resonant with a large loading inductor, it will still be an inefficient antenna because it has a very low radiation resistance.
Another side trip. In your setup, the antenna tuner is at the shack end of the coax. So the entire feedline is mismatched. This generates reflected power which reflects back from the antenna tuner to the antenna where it will reflect back to the tuner. With a lossy feedline, such as coax, the energy in these reflected waves is eventually burned up in the coax. Using a low loss feedline like ladder line can minimize this problem.
Your auto-tuner is eliminating the reactance it sees, allowing the currents in the antenna an feedline to oscillate at the frequency the auto-tuner has tuned. This would be even more pronounced if the ATU was near the feed point so the feed line was not part of the antenna oscillation. Also it is matching the resistance it sees to the receiver input. Once again, this would be more effective if the ATU was near the feed point so the transmission line could see 50+j0 at both ends.
I disagree with your premise that the antenna tuner does not change the antenna. When it cancels the antenna's reactance, it adds loading to the antenna to change its resonant frequency so that the antenna oscillates a different frequency. This is no different than adding inductance or capacitance to a tank circuit to change its resonant frequency. I propose a new term for antennas: "natural resonant frequency", the frequency at which an antenna resonates with no added loading inductance or capacitance. Because when you add capacitance or inductance to cancel reactance, you are changing the actual frequency at which the antenna currents oscillate.
As a ham I often tune by noise before transmitting and adjusting power/SWR.
I’ve been thinking about this topic quite a bit since first seeing Kevin’s interesting video. At least as of today, here’s my (another) two cents on the subject.
I view the antenna system as being comprised of four components: antenna, matching network located at antenna feed point, feed line and antenna tuner (Note that I’m keeping baluns/unbaluns off the table for simplicity). As to the antenna, I think its performance will be optimal if it’s resonant for the band of interest. Given a resonant antenna and an assumed feed line impedance of 50 Ohms, the job of the matching network is to transform the antenna feed point impedance to 50 Ohms. This should result in low SWR on the line. This begs the question as to the role of the antenna tuner (in the receiver).
I noted one comment in which the author suggested that the antenna tuner helps to make the entire antenna system resonant. This doesn’t seem quite right to me in that I think you want only the antenna itself to be resonant. According to (ruclips.net/video/zhsXIyq64Wc/видео.html), at least to the degree I understand it, an “antenna tuner” is used to compensate in scenarios where you are driving an antenna with frequencies off of resonance.
Happy Holidays! - Jim (KK7CSC)
Your right, an antenna tuner does not make the antenna resonant, it's a transformer that let's the radio side see 50 ohms at any frequency in its range. The antenna side of that is resonant on whatever frequencies the antenna is resonant. Having the transformer (tuner) is doing nothing but transforming the impedance of the antenna on that frequency to 50 ohms, which allows more energy from the antenna to be transferred to the radio.
The tuner does nothing to the impedance of the antenna on any frequency, only the physical parameters of the antenna and it's surroundings can change the resonance of the antenna.
Very clear and helpful explanation. Thank you, sir.
Happy holidays Kevin, thank's for all the interesting topics these past months.
The ATU is going to match the Antenna to the input impedance of the Tuner but we can use an 9:1 or 16:1 UNUN to couple a Longwire antenna to the radio.
Yes, assuming the longwire is medium impedance (e.g. several hundred Ohms) at the frequencies of interest, it makes sense to use a 9:1 or 16:1 unun at the antenna to reduce the impedance down to nearer 50 Ohms for connection back to the shack where it can get some final adjustment using an "ATU" to make it exactly 50 Ohms resistive presented to the receiver.
A radio receive amp is non-selective, therefore if your antenna is receiving a signal at its resonant frequency, that will engage the radio's AGC to desensitize the receive amp. When you change the resonant frequency of the antenna with an antenna tuner, the signal you want is the dominant signal, in turn stopping that other signal from desensitizing your receiver's amp.
Just a dumb guess.
Yes, the tuner acts like a preselector. As well as optimizing the transfer of energy.
Its a lost art with automatic, tune for noise first.
Excellently explained ! Couldn't be better . I am from India and learning to be a ham. This here explained a basic findamental so well. Thank you !
Could you please elbaorate more on which LDG tuner model you are using and details on yhe doublet antenna
LDG Z11 pro tuner.
Search my channel for doublet and you'll find the video about the antenna.
Helpful video, Kevin. Thank you. I think much of the confusion about this subject results from the name “antenna tuner”. These devices are actually impedance matching devices, not antenna tuners. I.e., as you point out, they don’t change the actual antenna, only the coupling of it to the feed line. At least that’s the way I think about it. Meanwhile, enjoy you time off and Happy Holidays to you as well. - Jim (KK7CSC)
It could be said electrically they change the antenna with the adjustment of the reactances to resonance
Antenna tuner is the correct term. It changes the antenna's resonant frequency with loading capacitance or inductance, thus tuning it to a new resonant frequency. Resonance is about oscillating currents, not necessarily about physical size. An 8 foot mobile whip can be made quarter-wave resonant, for instance, at 40 meters, by using a large loading inductor.
An antenna tuner also matches the radiation resistance of the antenna to 50 ohms, much like a transformer would. Perhaps the antenna tuner is misunderstood because it is a dual function device.
IMHO there needs to be a question in the General Pool about antenna tuners and antenna resonance. I think the only way to stomp out this misconception is to force amateurs to learn it right when they study for the test.
I think what you are missing is a very important point. If the tuner allows more signal into the receiver- it also allows more noise into the receiver in an equal amount. If not then you are saying that the tuner knows the difference between noise on the RX frequency and signal. an obvious impossibility. Yes, signals were louder, but so was the noise. The waterfall display color clearly shows this. This is basic S/N theory.
Dale W4OP
Yes, of course the noise floor comes up. I didn't miss it, it was just so obvious that I didn't feel the need to point it out.
@@loughkb So, the signal to noise does not change, then what is the tuner helping with besides making everything louder? All of today's receivers have more than enough gain to allow for low gain antennas (i.e. mismatched antennas, Beverages, Flags etc) to overcome HF noise figures.
@@W4OP LOL!
@@loughkb Deos the tuner allow you to receive a signal that you could not receive with just the antenna? Perhaps a weaker signal than the one in the video?
@@andrewking3087 It can, when applicable, certainly make some CW contacts much easier on the ears. More signal for the filters to process.
Along those lines, digital modes would be a bit better detected by demodulating and decoding software. Less dropped characters in RTTY or PSK31. A bit less snow from less AGC action in an SSTV image.
And there's the additional benefit of getting the most out of the antenna across the spectrum, rather than just at it's resonant and harmonic points.
Kevin, what about if you just have a long wire connected to a portable SW radio with a miniature jack? Will a tuner improve receiver performance?
In some ways. The tuner will act as a pre-selector. Reducing nearby out of band RF that could swamp the rf pre-amp in the receiver.
It will also improve the transfer of energy on the desired frequency range by creating an impedance match between the antenna and the receiver.
Manual tuner is first tuned for loudest audio signal on frequency of choice so I say yes it does work for receive only radios.
Hey Kevin that was a great video about the short wave and antenna tuner. I do remember that gentleman of ham radio and short wave. And I remember watching what he had to say, what are you enjoyed your video about you went into a more in-depth reason why it is good or if it’s not as good. And I really did enjoy the demonstration. How do you also hope you have a good and safe holiday enjoy the time for yourself if you don’t put out any videos before Quartzsite be safe.
73
WD5ENH
Steve
I thought this was obvious. the impedance mismatch is a barrier that acts both ways and causes part of the signal energy to reflect back to where it came from. if the source of the energy is your radio (when transmitting), then you have the normal reflection of transmitted power. if the source of the signal is the antenna (when receiving) then some of the signal power reaches the radio and the rest is reflected back to the antenna, effectively reducing the power of the signal received.
great content btw Kevin and your channel is one of the best out there.
Excellent video. Very clear and concise. It is good to know that an antenna tuner does indeed improve the reception for SWL’s! TYFP!
Merry Christmas/Happy Holidays. Thanks for yet another good vid. Will be missed. Enjoy!!!
It was really interesting seeing what the impedance looked like across the spectrum. I used to imagine it as a continuous slope but instead it spikes all over the place. Great vid and thanks again!
Good job.
The frustrating part is its name - Antenna Tuner. As you explained it does NOT change the antenna. That element picks up RF energy more efficiently at frequencies close to or at the element's resonant length. The feedline has the same SWR - doesn't change. The Antenna Tuner changes the impedance between the feedline and the radio. There is a theorem that says something like this. Maximum energy transfer occurs when the source and load impedances are the same. The tuner does that. Doesn't matter which way the energy is flowing - transmitting or receiving - the transfer will be optimum when the impedances match.
Good job!
Bob - W6OPO
Hi, yes they help, used one for years and increases audio volume on some bands using just a random long wire.
Good video. I have a tuner and I have done similar experiments to prove to myself that the tuner helps with receiving as well. Anyway thanks for the video and showing your VNA and receiver for the proof for all.
The tuner work like a band pass filter in certain way for that particular wave range you are working on?
Interesting stuff. Is the antenna tuner you are using a passive device? I've e been playing with my antennas over the last little while. I mainly am interested in Mediumwave DX and have a couple of antennas , two flags, a delta loop and a youloop. As you described, the impedance varies with frequency. 200 to 1000 ohm on the one flag antenna, as measured with my NanoVNA at the two ends of MW. So getting a linear match across the whole MW band is impossible with just a fixed balun. Would some kind of adjustable LC circuit help? PS i like your postcard of Cape Town. My hometown. 73, Vince
If an antenna tuner to brings signal up, you have a problem with your antenna as its probably not constructed properly. If you have a good balun and coax It should not make any difference. Only on transmit is the match critical enough to make a noticeable difference.
Very helpful explanation and demonstration. Much appreciated.
Excellent presentation. I really like the tone of your videos and the thoroughness of the information. I do shortwave listening with an Elite 750 with a 6/10/20/40 OCFD and I've been struggling with performance. This should help.
Would a jfet preamp, with a very high input impedance, work better with whatever length of wire you are using? For receive only.
It wouldn't load down the antenna and most of the signal voltage would be seen across the 1 - 10 Mohm input impedance.
I did this for a direct conversion receiver I made.
The preamp was a J310 jfet in a self bias config with a 10 Mohm gate resistor.
The jfet fed an emitter follower.
The overall gain was about unity but the input resistance was now 10 Mohms.
It made it so a 2 ft telescoping antenna worked really well.
Of course the long wire still worked somewhat better but the performance was very good either way.
The only other issue was the preamp was also picking up 60 hz, but an appropriate choke going from the antenna to ground removed the 60 hz and didn't affect the hf.
The information presented here makes a lot of sense. I voiced a similar opinion to yours and got shouted down, so I feel vindicated that someone with your experience and knowledge makes the same points so clearly. Season's greetings to you Kevin.
The winter Solstice was big in the old pagan religions and the days around/near the solstice have been incorporated into the younger and newer religions as some form of holiday from work with the calendar rolling over 10 days post solstice.. Now, being descended from Irish and Danish ancestors my Celtic DNA prefers the old celebrations on the Solstice complete with a big feast, lots of booze, and a good orgy. So happy holidays to you also (a few months in advance)
Well my rig got better as I tuned . I tuned my dipole. My rig ignored off band signals better but we all know the broad band receiver is not picky.
I commend you for trying to explain the fundamentals of antenna theory. But the next video you do, please get all the facts correct, make sure all graphs and photos and drawing are correct. I am not, Not bashing you. But I am or should I say retired engineer from the broadcast industry and your talk was kind of confusing to me. I know what you were saying. But to someone who has no idea of how all this works would be totally out of phase on the subject. So good job on getting the word out there, Do your home work a little better, don't let the dog chew up all your work, lol make sure your graphs are correct. Don't try and explain a wrong drawing, make it right the first time then do a video. 73 and good luck. 👍🏻👍🏻
Tuners make Reception much better by bring out the Weak Signals out of the Noice Floor,
Nicely explained video.Yes an antenna tuner helps but there is no substitute for a good antenna in the first place.For SW listening it's been my experience to avoid antennas fed with coax.Ladder cable being the far better option.The braid on coax lets in all sorts of noises and interference which is not needed.🐻🐵☺️👍
That was very helpful thank you. I have subscribed with thumb up.
Dang, that was educational to this newly minted general ticket holder! 73s
I am glad to see that you are also a metal detectorist. I started with a Garrett AT Pro.
Noticed the hat,,, are we sending radio frequencies in the ground now? New channel content coming?
I had no idea if a dipole and a tuner would work,but I made one anyway for my shot wave. It works, OK. I did get more channels than I did without it. I still want to find a better way to listen to my shot wave thow.
I'm just watching your video now. You're explaining a subject that most of our colleagues have some difficulty understanding: impedance. Congratulations on your presentation. It's practical and straightforward. By the way, what VNA do you use?
It's a mini VNA pro
www.dxengineering.com/parts/wmo-minivnaprobt?seid=dxese1&gclid=Cj0KCQjw8--2BhCHARIsAF_w1gy2ou75jg7Sdpx0AlfTXaezEuaDTeJy0E3F8X2Yy5WY1i3I1YatkBIaAvPHEALw_wcB
Very well explained to this beginner, thanks.
Happy Holidays Kevin! 73's de WD6FIE
now on that same line of thinking , would it be best for S.W.L to have a remote tuner at the base of the antenna connector before the coax run?
👍 my R390 receiver has an antenna trim built in...
For receive, preamp works best, overcomes such mismatches
The word "across" does not have the letter "T" in it. Stop adding a "t" that is not there.
The old SWL receivers had antenna trim or preselector to help match the antenna to the rig.
I think it's for to retune the receivers preselector circuit when the antenna pulls it out of tune. For sure it helps to match the antenna, but I'm not sure if it can solve the problem completely.
I have to try my Hammarlund HQ100 some day with the tuner and without it and see if there is any difference.
At the moment, I have a 55m long doublet with 240ohm twin lead feedline.
Cheers: OH8UBJ/Juha
Thank you, Kevin. 🇺🇸 😎👍 ☕
Great review Kev 💯👍
Thank buddy
Excellent vid. Have fun on your time off.
The theory of reciprocity says a tuned antenna that is matched for optimal transmission must perform better on receive whilst the transmission match exists, but some ATU’s drop their tuning relays on receive thereby mismatching the antenna.
An ATU is no. A manual tuner works well for receivers.
Yes, of course.
My ATU has L and C up and down buttons on the front face. Has been used successfully many times for SWL. Just play with it until signal and noise peak.
Happy New Year Kevin. Very nice video.
Thank you! I learned much!
Happy Holidays Kevin de k0taz
Tuning the antenna increases the signal as you showed, but also increases the noise. So the signal to noise ratio is the same, regardless of the S--meter reading. That's why beverages and receive loops work. They provide a good S/N Ratio even though they are non resonant . Sensitivity on HF modern receivers is not the problem. Their Noise Figure is way below the atmospheric noise level. So they are more than sensitive enough. The name of the game in shortwave receiving in having a good signal to noise ratio, not the highest S Meter reading. You should have mentioned that the best reason for using a tuner on HF is that it acts as a pass-band filter, reducing strong, off frequency signals which will degrade receiver dynamic range. That is more important than trying for the highest S Meter reading.
SNR is a different topic and outside the scope of this video.
Just getting back into SWL, replaced my ancient Sangean with a sweet Tecsun PL-880, a really nice radio. I have 3 poles and 30 metres (98 ft) of wire suspended in my backyard but am learning there's more to it than throwing up a length of wire (which works amazingly well, but I'm learning that to get a quality signal some learning and fiddling is needed). I need to learn about impedance, and videos like this are great, thanks so much from Melbourne, Australia!
For SWL, is using a 1:1 BalUn (placed in-between where the antenna first connects to the Coax feed) still a good idea to help remove RFI if I'm also using an antenna tuner at the radio antenna input? Or is it redundant?
That would help to reduce common mode noise. Hashy broad RF noise that gets onto the antenna system and travels down both conductors of the feed line as if it were a single wire. It wouldn't help with any kind of carrier noise. A narrow signal generated by something.
Rule 1 .. Whatever works for transmitters works the same for receivers. kc8zul
Rule 2 any antenna beats no antenna at all ; )
Great video thank you!
Yes, but your hat gave it away.
I understand now, great showing how it works rather than explaining with theory only. Did you use the AH-705 in the test?
No, an LDG Z-11 pro.
Merry Christmas!
Very Nice indeed !! By showing your experience by video !! You have explain it !! Two Ways !! ✍🏻😉
Great clarification video, Kevin! It presents a very nice way to explain to someone WHY the antenna tuner is beneficial also for receiving signals! 👍
I have an MFJ-901B antenna tuner which provides an SWR of 1. You have answered my question concerning reception. I don’t have hi tech ability to measure impedance so I must assume the impedance is good, based on the SWR. Your video is very revealing. Thank you!
For the past twenty years I've used an antenna tuner for my SWL pastime. No matter how good or bad the receiver, it always made a difference, as you amply demonstrated.
Now that I'm licenced, of course I use one, as I've no wish to damage my equipment.
So, good all around, in my view.
Kevin….. I see ur AT Max hat. Do you do some detecting ?? I haven’t got out in a couple years but own a Teknetics Gamma 6000. A lot of fun. Frozen tundra up here in Northeast Minnesota now. Thanks for another great video and 73. W0ZRK
How great to see it.
Thanks for this very helpful and instructive video, Kevin - greatly appreciated.
Merry Christmas!
Scott D. Majors
de K3SDM
Hey Kevin,
⛄ Merry Christmas & a MOST JOYOUS Yule 🎄 to you & yours!
Have fun playing with your new toy, hope to see it soon. My new MGK-269D PRO should be coming in today, so I KNOW how you feel about your "toy" 😁
See you in the New Year, take care o'yourself Brother and stay WARM!
L8R 🎄
Hi. QUESTION. If you have an aerial correct wavelength for the station you are listening too. If you introduce an aerial tuner does it increase the signal strength by improving the Q of the aerial. Cheers from old George.
No. The antenna is only going to 'grab' so much signal out of the air. If you're system is resonant for the frequency you are receiving, the transmatch would only introduce a small amount of loss. You may reduce the energy from other signals on different frequencies though, possibly reducing interference or desense of the RF amplifiers in the receiver.
@@loughkb Many thanks. I grew up with Thermionic Valves whereby the RF Amplifier was wideband. No band pass filters. ATU were as big as the radio. They matched impedance and also acted as band pass filters. Sometimes the knobs were marked sensitivity selectivity. The ATU increased the wanted signal by increasing the signal to noise ratio alowing the front end RF amp gain to be manually adjusted. It's rare to see an ATU as good as the old ones. Modern radios have band pass filters built in. Less knobs to adjust. Thank you for your reply it confirms my thoughts on modern ATU. Ps one of my old radios weight was 18 stone without power unit or ATU and it was only a Marconi DF Receiver ex ww2. No Transmitter. Cheers from old George just getting back into radio. 👍🤠🇬🇧
Great Video !!! I plan to be in Quartzsite mid January and I plan to attend QuartzFest 2022 for my fourth year there !!
uhhh. your illustration at 4:05 is a full wavelength. not half. 😉
okay you corrected yourself.
What were you using to view the impedance?
miniradiosolutions.com/minivna-pro/
that was a great demonstration. I do a lot of short wave listing. antenna tuners some times pre selectors do help on fixed antenna. I use a MFJ analyzer to set tuner to 50 ohm. also I found a outher benefit. the tuner is aet to a frequency. everything else makes impendence go way down or up.makeing a high Q point. with strong stations or noise not in what you tuned to can over load front end of receiver. helps drop noise floor on selected frequency as well. this helps pull out weak stations. 73's
Thank you for taking time to create this informative video. The knowledge you share is helping hams improve their stations. 73 BretC/AC0AE
This is really interesting - Not too technically inclined, but I'd live to give this a try as I am mystified by, despite living in SE Texas, I don't get a whiff of the tropical bands between 3 and 4 MHz...FT-991a and a Cobra Senior folded doublet 140' in a somewhat inverted vee with LDG tuner, would love to see if this helps me pull out some of the smaller stations out there. Thanks & 73 de W5VOX...
Thanks for such an informative video Kevin. Merry Christmas from Dubai
Time domain waves
Nice video. So, will an antenna tuner help with a regenerative receiver as well?
It should help with any receiver. The better the impedance match, the more energy from the antenna to the receiver.
more signal is one thing, but how is the SNR? also is it only impedance mismatch, or an out of resonance antenna is also attenuating? how about just using a hi-z preamp instead?
I would say as well instead of instead.
@@loughkb hmm.. not sure how can you utilize both together tbh. Tuner output is 50ohm already, so it'll be a mismatch if put before a hi-z preamp, which espects KOhms at its input. however if using the tuner after the amp, my guess it'll have no benefit as it'll be separated by preamp from the antenna, thus cannot influence the antenna by balancing out its capacitance or inductance.
Thanks for your video. Very informative. Seeing as you have a wide audience re your Christmas greeting, remember it's not winter everywhere. It's summer down here in sunny Tasmania. Merry Christmas.
A novice in radio, not even a license, this topic interested me months before I saw your video. I had heard that a tuner would not affect receiving but I thought it would, for the reason you cited. Thank you for your experiment. Great video.
Thanks for a very informative video. As a long time SWLer I will be seriously looking at antenna tuner.
Best wishes and thaks again