Using a Manual Antenna Tuner: Ask Dave Episode 5
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- čas přidán 14. 07. 2015
- Manual antenna tuners are less expensive than the automatic ones, and are perfectly okay for your station. This video shows how to tune a manual antenna tuner, both with an external SWR meter and with the SWR meter built into your transceiver.
- Věda a technologie
I've been licensed as a technician for 7 days shy of a year as KN4OXI. I've been a general now for a month and a 1/2. Your instructional videos have been extremely helpful for study and/or application. This one will assist me with 3 current projects after I watch a few more while taking notes
THANKS - 73s
Thank you Dave for this easy to understand tutorial. I am just getting started in amateur radio and learning what I need to learn and there is a LOT to learn as you know. And now, thanks to you, I can make an informed decision on what to buy.
Dave, this is by far the best (only?) attempt I've seen on youtube to explain the internal workings of a tuner. Thanks!
I recently made an eBay purchase of the same MFJ 901B tuner you use in this video. I have been looking for several days for a tutorial using this tuner. Great tutorial. Thanks!
when I first started in ham radio I used a incandescent light bulb, to tune my transmitter. I went thrue a few finals before I got enough parts to build a tuner, then as I got more money I finally bought a used one. nice hobby and you have a nice video.
Been using a manual ATU all my life. A little amused by people who think they're ineffective or hard to use, but I guess times change. With my Stone Age MFJ 949E I can load up a barbed wire fence. Wouldn't think to key down without it. Great video, Dave.
For those who find this all a little overwhelming, it's this easy: tune inductor and both caps to most noise. Dial up as little power as possible on the XMTR. (5 - 10 watts is good.) Key down and tweak ANT and TX caps till you get no reflection. Dial up 30-odd watts and tweak caps again, if necessary. Then 50, then 80, and so on. In most cases you can tune up 100w pretty quick like this, and with experience you can eventually tune up most hard cases too.
Very freeing, let me tell you. Thanks again, Dave.
Thanks Rob for bringing the MFJ-949E to my attention. I am new to all of this so I pay attention to what equipment I see others using. That ATU is a good choice for me as I can afford to buy a used one on my budget.
@@graywoulf Good deal! If you don't have a good ground (upper floor, portable ops, etc.) I find the MFJ artificial ground is also a good investment. It's basically an antenna tuner for the counterpoise you would otherwise connect to the "ground" post on the ATU; it tunes up the same way as the ATU. Costs about as much as the 949E, but unfortunately isn't as common on the used market (though I do see it sometimes). But it solves many feedback and RFI problems, and allows you to tune up even less promising radiators than the ATU alone.
With these two things I've been operating QRP through 100W to random wires for 25 years now, and have had a blast.
Best of luck!
Little late to the party here, but I'll chime in anyways because I liked what you had to say. I recently bought my first HF rig and upgraded to General, and in my current living situation having resonant antennas for every band on up to 10 and even 6m just isn't possible. I decided on an end fed random because I can use something with a bit of length to it, I just can't be putting up a tower or anything higher than 35 feet or so which I figure gives me a pretty decent length to work with if I do an inverted v, or even a sloper. I also like to experiment, building antennas specifically as well as learning about transformers and such to balance them, but I digress. Basically, my research on such a set up and knowing what my radios internal tuner is capable of (basically good for 3:1 or under), before I even set things up I knew I'd more than likely need an external tuner of some sort. Being a new-ish ham, and certainly new to a lot of the set ups used in hf, I weighed all of the options between auto or manual as I didn't want to overcomplicate things for myself. I found that I was naturally gravitating to the manual, despite a lot of folks saying they suck, autos 10 times easier, and all that. Automatic would be easier I suppose if it worked the way it was supposed to then thats all fine and good. But then I feel like I would lose a lot of control when maybe I just want to make a little tweak here and there. Plus, I don't think they're hard to tune up just about anything with on any band. I like the MFJ versa tuner with the cross needle meter and it even doubles as an antenna switch. I guess we all have different aspects of the hobby that motivate us, for me I feel like I am more in tune with how everything works together when using a manual tuner and seeing the difference in settings from one band to another. Thats my opinion on the matter anyways, and one huge factor for some folks might be that a good automatic tuner is going to cost quite a good chunk of cash. That cash could be better spent elsewhere in the shack Im sure, at least in my shack anyways. I picked up a barely used MFJ 941E on fleabay for $20 untested, luckily the gamble paid off and it is pretty much brand new and calibration is easy on them too. Guy even threw in a brand new 12v wall wart to power the light in the meter, can't beat a deal like that. My next project I think is going to be collecting up some parts, like a decent roller inductor, and a couple nicer variable air caps, and build myself a more robust antenna tuner just because I can. I'm not against automatic tuners by any means, we're all different. But, I also think there's some things a decent operator should be able to do before jumping ahead to Extra. Building at least a simple antenna, be able to build a simple swr bridge, know how to at least use a manual tuner and understand the basics of how it works, etc... seems there are a lot of "Extras" these days who memorized the answers to 3 question pools and marathoned all 3 exams in a weekend and are on Facebook a week later asking how to get his "SWR's" down. SWR's? I only have one SWR to deal with, unless I'm running more than one radio, then my advice would be to simply work on one at a time 😂.
Thank You so much, David. All Your videos are very, very interesting. Thank You for Your way to talk English, as well. That helps foreigners to understand every spoken word. Greetings from Germany. (Mike, DL2XAM)
Another GREAT video. THANKS! Beginner Note: Antenna tuners come second. A tuned - matched antenna comes first. Can't obtain a tuned - matched antenna, to old, HOA problems, no space...etc. Then a tuner is plan "B" but never plan "A". This should be mentioned to beginners. "But my radio has a built in tuner" okay be lazy and connect it to a piece of metal and make the tuner do all the work. But don't wonder why there's loss. And "yes" there's loss. This is simple math. The antenna tuner is a placebo and most of the time superfluous when a correct antenna is in place and used properly.
Thanks, Dave! An 84 year old ham just gave me this thing to learn how to use! EVERYTHING is on CZcams now!
Hi Dave, I have to say a big thank you for these videos because I recently passed my advanced exam here in the UK giving me a full amateur radio licence equivalent to your extra class! I failed the first time and found your videos on capacitance and inductance very helpful because seeing what happens in a circuit and parallel circuits really brought home the message, so once again thank you for taking the time to produce and star in these educational videos because sadly there are not many on CZcams geared towards the UK syllabus but the subjects I needed to reinforce my learning are universal in our great hobby!
73 Dave
De Steve M0LVL
Steve, congratulations on your Advanced! And thanks for the kind words. 73, Dave
i want to extend a hardy thank you. on 7/11/2015 after watching your vids. i passed and acquired my extra class ticket at the firecracker hamfest in salisbury n.c.. albeit, by the skin of my teeth, i missed 13 and not 14 answers. and that's all that matters.
Congrats on your upgrade! 73, Dave
Hi there Dave, Thank's for your informative, interesting video regarding antenna tuning/matching. Thinking back to my early days with HF radio (Brit army). We had the old "Variometer" tuners with just about the whole range of sets. They had a meter which you set for Max. reading by use of the rotary inductor and just one capacitor. We accepted that we were tuned by this method on either a vertical or a wire end-fed antenna. No one seemed bothered about SWR or knew anything it in those days. It was not until I made a "Reflectometer" i.e. with a enameled wire threaded up under the coax loop and resistively balanced out to 75 ohms or below etc. etc. as per the "Technical Topics for Hamateur Radio" book from the RSGB. This was to use a Pi config. tuner for a vertical half rhombic on low VHF. I was part of a unit team testing these out using the Larkspur C45 sets. We had an out station up in Denmark, equipped with a tuning set-up that I had made in my shack .Another one on the North German coast line using the same and my station back at Hildesheim. (N. Germany). This was all organised by our Regimental signals officer who had read an article in the "Gunner" magazine which he had picked up in the "Mess". The system worked out great and we had coms between Denmark and N. Germany on sets that we often had problems with mobile to base over 15 miles range. At that time it seemed like a miracle in using about 200 feet of wire in an inverted V with its 400 ohm terminating resistor to work that kind of distance on VHF. I used the same system successfully with a 1 watt O.P manpack in the jungle of Malaysia to an HQ base station when the "Rebro". station broke down . The HQ station had the standard VHF ground plane vertical antenna by the way. 73 de John - G0WXU.
Wow, you've got some interesting stories to tell!
Thanks for the demonstration videos. Since I can't read apparently (I'm Joking) however having someone show me is gold! Honestly thanks. Nice pic of you checking out the flowers.
If you own an antenna analyzer, you can also use that to tune your antenna without putting a signal on the air. An A/B switch can be used to choose between the transceiver and the analyzer.
Great video Dave! Thanks for the great refresher course.
Awesome Dave!!! Oh and that forest looks like a great place for a field day!
Before I was a ham a good friend who was a ham and now a silent key, N8NLE demonstrated a manual tuner by tuning up a screen from a window and an aluminum ladder and preceded to make many cw contacts. I was entertained. I want to get an old Dentron or Johnson Match Box just to do the same thing. 73 W8XDX
Thanks Dave. Excellent presentation and content.
I was brought up to believe that a manual antenna tuner was a guy with a pair of side cutters.
Ade Larsen Hi Ade, thanks for your kind words. My antenna is a full-wavelength 80-meter horizontal loop. I've put a diagram together for a future video. I interviewed a ham friend of mine on how he approached his antenna problems, and I want to interview another before putting out the video. Stay tuned!
Thanks Dave. As a noob, I find your videos very helpful.
This was a great video, thanks! I always wondered what happens to the radio energy as it’s going through the tuner.
With a manual ATU with tapped inductor. You should not changed inductor while transmitting. Damage can occur to transceiver. That warning is in the instructions with these types of ATU's
+Shawn Rullens True! Thank you.
Dave - I enjoyed your video very much - thank you. You are a valued source of clear, concise, technical information in this wonderful hobby of ours. Please never retire. I have a question regarding the diagram outlining how to connect the transceiver to the SWR Bridge, to the Antenna Tuner, to the Feed Line, and the Antenna. Is the procedure the same when using an Auto Tuner?
MB
Good plan, good demo. I’m surprised you didn’t mention antenna resonance as a prime aspect of this process.
I just found your series, have you looked at updating any of them. It is 2020, I have bought things from several SK sales, so I am not using "new technology". If there is no need to update the actual information, that is fine. it seems pretty basic, or at least well explained. I need to get the latest ARRL antenna book. Thank you for taking the time, and the pics are beautiful. I can no longer live at high altitudes because of respiratory issues, the area you live n is so beautiful, I lived in Colorado Springs and Denver metro at different times. Kansas is my home now. K0XHF here. when I get my shack ready, I will be looking for you.
Just got am mfj-945e. Works great. Thanks for the infp
Thanks for this. I just got this same tuner at a hamfest so its was very helpful
Thanks Dave! I have an ATU and a Manual Tuner. I bought the latter to use it for DXing with my receivers. I have an MFJ-974HB that has a power and SWR meter built in. It is a bit bulky, so I may get a smaller manual tuner for DXpeditions. 73 from PY3WHO /PY5136SWL.
Great video and easy to understand for a new ham. Thanks!
One point I noticed- It's best practice not to operate the forward/reflect switch (or any feedline switches for that matter) whilst transmitting. You can get arcing and burnt contacts as well as possibly damage your finals.
Whoops just read other comments!
Thanks for your instruction kind sir I now understand what I’m trying to achieve much appreciated 🙏
Really appreciate these videos, thanks.
Thx I'm using an old archer tuner for my indoor di-pole base antenna, would be pretty tricky without it!
As a recent general class amature , I appreciate your videos and the excellent explanations. David Byrd KN4BHS
Thank you. Get on the air! Maybe I'll hear you.
thank you form your clear explanation, I learned my swr and anttene tunner are not standing in the right way
I just found out I also had mine backward too cause of this video.....thanks DAVE...
Nice explanation, Dave. Thank you!
Kenwood 590
Exactly what I needed. Thanks!
David - good data but I think you should have mentioned that if you use the rigs build in SWR meter you need to have the AGC on and the RF gain to Max. I usually turn AGC off, turn RF gain down and AF gain near max. Then I adjust RF gain for strong enough signal with minimum noise. BUT, I have to remember to go back to AGC and max RF gain when using the tuner again.
I just got it!
Finally!!!
You did something in this video that I have heard is a pretty big no-no, which is to switch the inductor while doing a transmission. The problem I expect is that the SWR could go through the roof and that’s due damage to the transmitter while the switch contacts break and then make the next inductor tap.
Dave, I just bought a mfj 891e tuner and was disappointed it did not come with a manual! One is available online I can print , I guess I can go to Kinko's and get one printed . I would not have bought it if I had known. I will survive but I will look carefully in the future at the fine print. Thank you for your instructional videos . David Byrd KN4BHS
"No manual" is getting more and more common.
I love your videos! Thank you!
+Eric From You're welcome!
Outstanding and very helpful video. I owe you a donation
Super helpful. Thanks!
Top man, Andy from the UK
I use a CB half wave ground plane and a manual antenna tuner for 6 10 12 15 and 20 meters. Longest QSO on 20 QRP was France.
It's hard to be impressed when we don't know that you aren't in France.
A good explanation.
I have had my Extra for some time. The was a good tutorial and refe
And a good refresher. Thank you.
Any antenna coupler with more than two variable elements needs an additional power indicating meter at the output of the coupler!!!
Couplers with two variable elements are L-couplers. If you match an antenna with these, the setting is unique, as there is just one and only setting (or none) to match the antenna.
Three element couplers like T or Pi couplers have several ranges in which they are able to match the antenna. But these ranges have quite different efficiency! You will not be able to find the most efficient setting for your coupler if you can't check how much power comes out of the coupler. The VSWR meter shows just the quality of the matching.
I strongly recommend to add a simple field strength indicator to indicate, how much power comes out of the coupler. There are a lot of simple circuits in the web to build a simple field strength indicator. But without this little gadget you simply can't find the best setting! This is not my opinion, this is pure RF technology!
Some elder antenna couplers have such an "relative output meter" and a potentiometer to set its sensivity. But modern manufactures simply left these out to save a few Dollars for each coupler they sell. Instead they have added nice looking VSWR crossneedle meters - most modern transceivers have a VSWR indicator already integrated, so in the coupler it is really unnecessary in most cases...
...but the other meter really IS needed! So build one yourself and tune your couple not just for a nice VSWR but for highest output!!!
73 Andy DH5AK
Very useful explanation dear KE0OG Dave 👍👌
I have got an swr meter with a tuner bulit in for my CB but im kinda afraid to mess with the tuner
Thanks Dave
Dave how would i set up a manual antenna tuner with an amplifier and a swr meter
How do you “adjust the calibration”? Is the a adjusting knob o the back or something?
What is the ideal capacitance setting for the Tx and antenna when switching the inductor to find maximum noise? Fully meshed on both, or midway on both, or elsewhere?
As fully meshed is supposed to be optimally efficient I start fully or close to fully meshed. This generally provides a fairly broad Q once tuned.
I've tried other matches with higher/narrower Q thinking it may act to some degree as a preselector to help reject out of band QRM/QRN and to some degree end band noise. Are both the hi-Q and lo-Q matches just as efficient assuming the same indicated power out and reflected power?
Thank you Great Chanel
I have a low swr on 145.000 high swr on 147.000 should i use a tuner? 1.0 to 2,7high freqs
Thanks for another great instructional video to help us newbies along, Dave! That Micronta SWR meter is readily available on EBay and looks like it would be a decent choice for a shoestring budget ham newbie. I’m curious if it is suitable for a 100W rig? I figure it was designed primarily for the CB market (4 watts).
I've used it with a 100w rig. Seems to be okay.
Is the antenna matching unit good to improve preselection of a receiver? Which are the LP, HP construction? 3 decades back I had an up-conversion transceiver and frequently heard AM stations around 10100 kHz. There was no broadcast there. When I turned on the ATU (AT150) that "QRM" was dropped. Which tuner is good for this purpose, T match , S match ...... ? Recently I compared my K3 with a direct conversion transceiver and heard the unwanted signal on 30m band later on upper band also making that band unusable. Need a solution, this type of QRM is not predictable depends on propagation. You may give an answer in QST as many tiny transceiver owners could be affected.
I have a 1-1 swr meter on my radio to antenna and on meter in line ,,when i put a linear in line the radio meter gos to 3 and the in line meter stays flat why is that ?? and will a antenna tuner fix this ??? thanks
Nice video
Can someone comment on the _considerate_ way to tune one's antenna? Would not a long tuning session create a lot of interference? Do you tune at a minimal power-output?
...Thinking of getting into the hobby.
GREAT !!! Thanks a lot
Dave hi
I hv a Heathkit sa 2060a.
I am familiar with the tuning but there is a ‘sensitivity’ dial and a ‘set’ button. The manual gives almost nothing abt this.
Am I correct in thinking to transmit at low power and to turn sensitivity dial while set button is pressed in, and then to line the needle on the meter, to set?? And to do this to each band?
I appreciate your answer.
Thanku Dave.
Billy
N1mrk
Hello Dave my questions is. Is there an antenna Turner that I can use for 2meter and 440 all in one.i see the mfj-921&924 looking for all in one.
Thanks
Excellent video thank you very much. 73 By CE3HOT
Hi Dave, it is always a pleasure to watch your videos. I do have a question. I have an antenna tuner that has a small meter on it. I don't know how good it works, but it looks ok and the tuner seems to work quite well. However, due to the size of the meter and because of my failing eyesight I would like to place a second larger SWR/Watt meter in front of the transmatch. Is it ok to do this? It would really help me to see what is happening better.
Yes you can put these meters in series prior to the transmatch
what would the setup be with an amp in line?
Great video Dave, thank you. I have an MFJ-969 tune and it works quite well with my Yaesu FT-950. The 950 has a built-in tuner as well and I was wondering if I should even use it after tuning with the MFJ-969? I was concerned about having tuned with the internal tuner then trying to tune with the MFJ or vise versa so I reset the radio to factory default settings and have since left the auto tuner alone. Any thoughts on this matter are greatly appreciated, keep up the great work! I upgraded to Extra in March of this year having reviewed many of your training videos. Again, many thanks.
Frank, K6FLD
Frank D Hi Frank, I'm glad you found the videos helpful. You're right - either use the internal tuner or the external one but not both. Usually you can tell a radio to turn its internal tuner off with a menu setting or something. I'm not sure on the 950. Good luck with your HF work! 73, Dave, KEØOG
Does it matter how long the cable is to the tuner/receiver? Won't I also have some signal loss there if the cable is too long? Where can I get this cable that has the proper connections on both ends?
Yes, longer cables lead to greater losses. You can find cables with the connectors already mounted from several sources on the Internet. Try usacoax.com
Dave could you please confirm when measuring the length of one of the legs on a quarter wave dipole do you disregard any line that was wrapped around the connection screw and only measure the straight length or do you have to include any overlapping or or Loop as part of the full measurement of a leg
All of it counts that's in a straight line. If you wrap it around a mounting screw, the distance is that from the mounting screw to the other end of the wire.
I have an old RS SWR meter that's even older than that one!
Great video thanks Dave!!! Got a question for you Sir...i'll have in a few days a lovely well kept Kenwood TS 440 S...this radio already has a tuner inside...would be enough to tune a 102" whip for mainly 10/11/17/20/40mt band? Or i better add to the set Up an external tuner? The whip will be mount on the Roof's center of my Sprinter Mercedes RV...the Roof is made out of steel , so should be a good "ground" ...i'll maybe have as well place enough to fit some Radials at the Antenna's base...if it help .looking forward to hear from you...the whip is metal no fiber glass...73's hope by the way you and beloved one are Fine...here in Spain we do fighting hard against CoVid 19....all the best Steve ciao
Other option apart of the 102" whip , could be Buy an Antena Multiband HF one of those you got to move a cable between pin connection to tune on every single band...like the Outback 2000 antena or the Proxel X1...if you have any suggestion on other good antena for Mobile Car uses...i'll be happy to pay attention to your suggestion...the idea of the 102" whip is that i already have one with pl mount and spring bought from Usa from Breedlove shop...best again 73 ciao
Great video, thanks! Here's a question: Are some manual tuners better than others? I'd like to buy a manual tuner, hopefully one that I can take out in the field. But I also don't want to compromise on quality, especially because in the field I mostly use relative low power.
MFJ makes many antenna tuners, including QRP tuners. All manual tuners these days use the classic "tee" model. Two variable capacitors and a variable inductor.
? will my old ic-7200 work with the new ah-730 th.
Please put up a vid on tuning a liner amplifier lots of confusion about a tube type amp and proper tuning of it
thanks Pilgrim5
I don't have a tube type linear amplifier. My amp is solid-state and does not require tuning except to tell it which band and using. You should follow the instructions in the manual.
Dave I have a question. you used a micronta swr meter. I had one like that years ago. I used it for a cb radio. could that meter be used for any ham frequency and power.
Yes, for any frequency even including 2m. But I'm not sure how much power it can handle. It was made for the CB market back in the 1970s. 73
Was looking for different types of Antenna tunners explained like 3 knob type and 2 nob type what is good?
Most manual tuners are the three knob type. A tuner for a long wire may only have two knobs.
Ty!! Great explanation.
And as they say..
You can tune a guitar, and you can tune a piano. But you can never tuna fish! 🐟 🐠 🐡
Hi going for my Tech. lic. next week. I've ran CB radios for many years . do you tune your antenna in the same manner as a CB if your radio does not have a built in swr meter? looking to get a BTECH 5001 for both mobile and base unit , possibly setting one up as a emg. go-kit .
+richard imel Essentially, yes. Put the SWR meter between the radio and the tuner, then adjust the tuner for minimum SWR.
I have been struggling trying to understand the advantages of a feed point installed tuner. I am struggling so much, I am not sure how to ask the question. Assuming everything else is equal such as tuning range, power capability, and so on, is it always optimal to have a tuner at the feed point?
One of the LDG products says it will handle the problem of feed line standing waves. In my mind, this means only a remote tuner can solve feed line problems and a desktop model cannot? The desktop solves the feed line issue before the radio. Is that all we are trying to do, match the 50 ohm radio impedance or is there something else going on?
Love to see a video, Remote versus Shack Antenna Tuners
PS, Your the best on CZcams. I am in the process of watching them all.
Brad
N6GR
Thank you for the kind words. If the antenna tuner is at the radio, there can be very large voltages and currents in the feed line, and these can create heat in the feed line. If you put the tuner at the antenna, you will avoid these the losses. Unless your antenna is way out of tune though, you not going to save that much by putting the tuner at the antenna.
can you use the internal tuner in the radio to clean up swr as you change freq instead of retuning the ext. tuner each time on the same band ie as long as your on 20 meters
Maybe, but only maybe. It's generally considered best to use just one tuner--either internal or external. 73
David
Thank you for the reply. I am brand new at this and currently putting together my first hf station. I have acquired a Kenwood 570d with internal tuner, and am looking at a g5rv dipole as my first antenna. Trying to save up now for tuner, but after seeing your video i believe i can get by with one of those 901b tuners, as my radio does have internal swr meter. I just got my general licence on 2-27-17. i may just wait till after Dayton though as i think i might try to make that trip.
73
KM4ZJL Eastern TN
how about when/where/why to use an antenna tuner?
i guess an example would be, say I have an FT-450D, it has a built in antenna tuner capable of tuning out 3:1, but lets say im using a Windom or OFC dipole which is designed to have a fairly low SWR on multiple bands (i've heard 80-6m can be under the 3:1 across - though i think that might be a bit of a marketing claim). would it be better to let the built in tuner do its thing no matter what, or, if the SWR is already fairly low, just leave the tuner off?
from what i've heard, having the tuner on reduces the power? i'm sure its minimal, but with farther out of tune antennas, how would this effect "real world" performance? antenna on doing its thing, vs off with a bit of SWR (but still acceptable, up to say 2.5 or so).
It comes down to experimentation. Leaving the tuner on all the time is probably the way to go unless it misbehaves. Some of the verticals on the market (e.g., AV-640) are pretty spectacular when it comes to low SWRs across multiple bands, but they can be pricey. The OCFD is a popular antenna these days, but you might need a wider-range tuner than the built-in tuner. 73, Dave
Good basic information, though I personally wouldn't flick between Cal and Ref whilst keyed down but that's just cautious old me.
You are correct. My bad.
Hi David,
Really good video congrats the way which you explain i found very good, I'm struggling with a President Grand II and a sirio signal keeper to reach a better SWR value right now I'm on 1.9:1 which is not bat but i wanna do more, Yes i operate currently only CB and I think you convince me to get a antenna tuner, I tried all possible ways to get antenna higher, I've build a ground from a 2.5 m copper rot and is no difference if I connect the ground or not which lead me to idea actually maybe antenna mass reflectors are not working well, the antenna have a total height of 209 cm including the base coil but one radiant is only 65 cm I think way to small, but i don;t know how to calculate the proper size for them. I know for a 102 inch whip to use same length for radiants but the whip have no inductive coil so i'm a bit lost here.....
Cheers,
The 102 inch whip is a full quarter wavelength at the frequencies you're using, so needs no loading coil. Generally if your SWR is less than 2:1, you're okay. Getting it down further could take lots of work for little gain. I'm not familiar with the products you mention, so I can't offer much help there. Keep experimenting, and, of course, an antenna tuner might help.
Thank you!
I have 2 radios using the same antenna. I have the MFJ 941d. Is there a way that I can use the same tuner for both radios?
Yes, just hook up the tuner to whatever antenna and radio you're using.
I have enjoyed several of these videos and have learned a bunch. but the swr tuning in this video went way to fast and I could not follow. currently studying for my technical.
Yeah, it's about time for another antenna tuner video.
A NEWBEE Question?
I want to put up long wire antenna it would be a loop pattern around to roof edge of my home. About 12 inches above to roof, of course to get the length it would have a loop type configuration. 14 gauge stranded wire of 148 ft length, then a 9:1 UNUN and a 1:1 line isolater. Feeding to a FT-450d yeasu with a broad LDG matching tuner. Grounding the long wire on the opposite end from the feeder. So far I think it is working on 20m and up with an swr Under 2.2 across the bands. (I tried it on FT8 to a POTA station 1100 miles from me on a power setting of 50) Any suggestions on how to improve it to cover 40m and possibly 75m the voice end of 80m? Is the antenna to long/short, wrong UNUN? Thank you and 73.
P.S. does the wire have to be tight or can it sag between supports- about 10’ apart and sagging about 3/4 inch between them.
Is an "antenna tuner" and "antenna matcher" the same thing?
Great video. I am living in a ground floor apartment. A have one buddipole dipole antenna. If I put my antenna in the balcony, how much ground and side clearance do I need for the antenna?
There's no hard and fast answer. Simply do the best you can. Farther away from the building is better, but that might only be a matter of inches. Good luck! 73, Dave
Thanks Dave :)
73 de OH2EYS
I have the same antenna turner . Sometimes when I tune my antenna, the antenna knob well be on 3 ( for instance) and the transmitter knob well be on 5 or 6 why is that? should the antenna ,and transmitter knob be on the same number ??
Just the luck of the draw. No significance.
This is a really old thread but hoping for an answer. I have a Yaesu 817, MFJ-813 and a Z817 auto tuner. What is the order equipment should be connected, I thought that antenna into SWR meter, from SWR to the tuner and from the tuner to the radio, but I am just not sure, please help.
VA3LAM
THANK YOU AND 73
Connect the radio to the S meter. Connect the S meter to the antenna tuner. Connect the antenna tuner to the antenna. Tune for lowest SWR.
should the tunner in the radio should be turned off?
Dave, it seems like auto tuners are made to specific radios or brands, and a manual tuner could be used without knowing what I might own?
Thanks for all your videos. I have a Yaesu FT- 817ND radio, and a MFJ-971 manual tuner. What mode do I put the radio in to send a carrier for tuning. AM? and should I transmit the carrier at 5 watts or reduce it. Thanks KG7CQG.
You can put the rig in CW mode. You may have to use a menu setting allowing the buttons on the hand mic to act as a key, or you can simply use a telegraph key plugged in. The tuner you have has a QRP mode, so you may not have to use 5 watts, but can use a lower power. Good luck! 73, Dave
Ham radio kenwood 590
Why can't I us my antenna tuner be for my amplifier? If you put the amplifier in bypass mode anyway and antenna tuner turn in low power anyway.
Your radio output is 50 ohms, and your amplifier input is 50 ohms when the amplifier is on. Don't put a tuner between the two. If you're going to use a tuner, you have to bypass it when you're using the amplifier. Or, get a high power tuner and put it after the amplifier. You can use the high power tuner on either high-power or low-power.
I have two antennas that is no tune. I have an auto tuner the the five ninety and on seventy three i have a no tune antenna. the only problem is they will just take a hundred watts. i DO HAVE ONE ANTENNA THAT I HAVE TO TUNE. I have g-5rv. it has to be tuned when you change channels
Hey Dave, I have been watching every single possible video on antenna tuners that I can find in order to understand everything I can about this devices, I have a modem receiver that have this single wire antennas that come with a ATU unit "Two of them" each have a this totally miniaturized version of it.. but range on this particular unit really stinks. Now its my hope to increase the range by installing a good set of choked dipoles but don't know if I have not other choice but to use the same type of ATU? with the same value on the capacitors & inductor....your advice will mean the world to me!!
The radios that have internal antenna tuners that are usually only good up to 3:1 SWR or so. If the antenna has a higher SWR, then an external tuner often can tune up to 10:1. If you do use an external tuner, such as those from MFJ, turn the internal tuner off.
Thank you very much for your thoughts, the ATU that is in my modem is internal, I have been taking steps to disable it "Specially the Inductor, that connects the active element to the ground and I just plan to make my own tuned dipole antenna dead on the 433Mhz. so I can just do with out the tuning circuit..
Perhaps one last question... what would be the dBm or mW output of perfectly tuned antenna? using a frequency of 432.629 Mhz? thank you very much for your valuable time and effort! at 1.5 watts
In theory, if there's no reflected power, all power is radiated. But there are resistive losses in the wire or tubes in the antenna itself, so an antenna can't be 100% efficient.
So... not even a dead on perfectly tuned antenna will put the 100% of the RF Power in to the air? isn't there any type of exception?
Howdy. Very nice presentation.
Is there a reason to why most tuners are T -tuners ? I believe Pi -tuners provide more harmonics attenuation. Perhaps modern tranceivers have very good harmonics attenuation by themselves ?
Regards.
Electrically, a T tuner and a pi tuner do the same thing. They both help with harmonic suppression. Modern radios do not need any additional harmonic suppression and can be connected directly to the antenna and meet all requirements.
I’m setting up a portable station. The question I have is, is a small manual tuner better to use because of the power drain of an auto or is the power drain from the tuner not enough to be concerned about I love your videos keep up the good work. Also if you have any recommendations on an inexpensive but capable tuner for portable stations ( not qrp ) It would be appreciated
I’m setting up some experiments with the loop antenna in a horizontal position and will test 40 again.
The power drain from the tuner is small but not zero. I like my MFJ 993B.