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Welcome all to this group. I set it up as a generic group primarily for amateur radio operators that covers both commercially-made and home-built impedance matching devices used to match an antenna system to a transmitter (or receiver). Technically, what most of us call an antenna tuner is actually an impedance matching device, and probably in most cases it's attached at the transmitter end before a run of coax or open wire line to the antenna, so we're not tuning the antenna--we're tuning the antenna system. We're not going to be concerned about the term "antenna tuner" here, though, as most of us know what it is and that it's not usually acting as a true antenna tuner. Call it what you want, but most will call these an antenna tuner. I have several MFJ tuners, including the 939, which I like a lot, and the 3KW roller inductor tuner they make, as well as the smaller roller inductor tuner, a couple of "Versa Tuners," and a small MFJ auto tuner I plan to use for mobile use. I've never used it, but I also have their "ground tuner" that can change the RF electrical length of a ground wire from say a second story room to an earth ground below. Why MFJ? I've had great experience with their products, but I am aware that at times they fail to solder a joint properly or have other quality problems, and they've at times earned the nickname Mighty Fine Junk. There are other great tuners out there also. I just happened to pick up several of these at hamfests at a fraction of the normal selling price, and the price was low enough I bought some of these "just in case" I might need them sometime in the future. I ask that everyone treat each other with respect and dignity. No politics or religion here please (check your signature lines before posting). Don't be afraid to ask questions here. Donald -- AD8DY Formerly KJ3I

There was a thread in another group that got me thinking. The antenna tuners I have all have an SWR indicator. All mine are cross-needle meter types but they all read the adjusted SWR that the radio sees. Are there any that display both the raw SWR that is seen at the end of the feedline nearest the radio as well as the adjusted type? I could see that being useful, or at least interesting to be able to view both. Donald -- AD8DY Formerly KJ3I ---------------------------------------------------- Some ham radio groups you may be interested in: /g/ICOM /g/Ham-Antennas /g/HamRadioHelp /g/Baofeng /g/CHIRP https://rf-amplifiers.groups.io/g/main

I have two roller inductor tuners, both MFJ, one good for 300W and one for 1.5 KW (or maybe it's 3 KW?). I haven't even used either of them yet. I just found them at a great price for each of them, $50 for the 300W and $75 for the higher powered one, and thought they might come in handy someday. Is there anything a ham should do to maintain the connection along the roller inductor? I am not going to try to clean it myself before knowing if I even should. Maybe you just leave it alone until it starts not making good contact then move on to cleaning it? I haven't opened them up so I don't know if MFJ used silver plating on the coils and the rolling contactor or not, and I don't know if silver cleaner is a good thing to use. I'm new to this. The last roller inductor tuner I had I made myself back around 1980 and used it for a few years, then sold it along with my ham stuff when I moved to another state. I now have acquired several tuners and two of them are roller inductor types, so if these need some sort of cleaning from time to time, I thought I'd do that before using them. Donald -- AD8DY Formerly KJ3I ---------------------------------------------------- Some ham radio groups you may be interested in: /g/ICOM /g/Ham-Antennas /g/HamRadioHelp /g/Baofeng /g/CHIRP https://rf-amplifiers.groups.io/g/main

I had a Versa Tuner II for some 35 years. It was pretty beat up from many camping trips, so when we bought a small camper trailer (16'), I invested in a new one. First trip to altitude here in Colorado to 10 kfeet, I was able to use the new one (where the old one had never failed) to all of 20-watts. Above that, one of the variable capacitors arced badly. Once we got home, I removed the respective variable capacitor from the old unit and installed it in the new unit Now the new one works just fine with 100-watts at 'Colorado altitudes". MFJ over the years had cheaped out on the variable cap plate spacing. The original variable capacitor In the new unit, I could hardly insert a piece of printer paper between the plates. The old capacitor which is now in place in the new Versa Tuner II can take a couple of standard business cards between plates. The small spacing may work at sea level, but it sure didn't at 'Colorado altitudes'!!!! So if you buy MFJ antenna matching networks and plan on using them at altitude (as high as 14 kfeet in this state), better be prepared on changing out the variable capacitors. Dave - W?LEV -- Please join me. Dave - W?LEV

Happy to have joined this new group. Any comments about these 1623-1625-1644 (L mode with artificial ground) or possible bigger ones with roller inductors but without artificial ground 969 (T mode) or 986 (differential T mode). I guess the L mode or the differential ode are better? I need that for a 3rd floor balcony with aluminium railing, steel reinforced floor and ceiling with a FT-897D. 73 - Pierre - FK8IH

Icom AT-150 HF Automatic Antenna Tuner For Sale: The Icom AT-150 is an automatic external antenna tuner for 160 through 10 meters. It provides auto band switching with Icom transceivers by connecting to the ACC 2 jack on the back of the Icom transceiver. The rear panel features 3 SO-239 antenna inputs and one Hi-Z long wire antenna input. Controls in the top panel allow programming of the antenna inputs to specific bands. There is one preset frequency per band for even faster tuning. Power capacity is 100 watts. Minimum drive power is 8 watts. Tune-up time is really fast. The 13 V DC required is furnished by the transceiver. This one looks extremely nice. There is a smudge on it. It includes the almost impossible to find interface cable to go between the transceiver and tuner. It works as it should, which is really outstanding. With interface cable, and paper work for only $245 plus shipping from Florida. Thanks. 73, Ken, W8EK Ken Simpson E-mail to W8EK@... or W8EK@... Voice Phone (352) 732-8400 . .

Hi, All- Donald KX8K mentioned this Tuners group over in the Antennas group. I thought it would be interesting so decided to check it out. I like to build. My antenna tuner experience is fairly limited. I did build a coax tuner about 20-30 years ago, I think it was called the SPC? Anyway it is a slightly improved version of a popular design. Works pretty well. Just recently, very late in my ham career, I started working with HB ladder line. I have a 20 meter rectangular loop it feeds, vertically oriented, fed horizontally polarized at bottom center. What I wanted to share with the group is how happy I am with my latest HB antenna tuner. It is the PA0FRI S-Match design. I just have it cobbled together right now but do plan to finish it in nicer form. Luckily I had had time to accumulate some pretty nice parts for the tuner, including the big Johnson edge wound roller coil, a big 100pF bread slicer that looks good for around 9KV peak, a stack of two T300-2 toroids for the balun, several fixed vacuum caps for padding, and various heavy duty knife switches for them. It ought to turn out pretty good. That loop has the right length of open wire line so I can even get it to tune up on 40m, where it is 'almost as good' as my 40m sloper dipole. All this will lead me to try a few more open wire fed antenna types now, I do have some designs in mind. Fun!, If anyone is interested, you can search PA0FRI S-Match for a good page on the subject. That's where I took my inspiration from. 73, David K3KY Derwood, MD

The following link appeared on the NANOVNA group. It certainly is useful to these two groups as well. /g/NanoVNAV2/files/Impedance%20Matching%20EBook%20-%20July%202021.pdf -- Dave - W?LEV -- Please join me. Dave - W?LEV

Anyone out here have issues with the 994 BRT remote tuner? The day after the 1 year warranty expired, it expired. All tests recommended by factory tech were good, but it still will not tune. IC-746PRO internal tuner loads my 43ft DX Eng vertical OK through a4:1 UNUN, but the tuner worked better. MFJ received it for repair on Sept 7th. here it is Jan with the 7th in a few days and not repaired, replaced or offered a deal on a new one. I worked great for the year. I can't believe about 75-80 wats at the tuner input could destroy it a 600 watt capable tuner. Anyway, any ideas?

Hi Don, well I have a 100 watt IC746PRO that I am using, but 165 feet of RG213 buried in a pvc conduit, I never checked the wattage at the tuner input but calculations for loss per hundred feet it should be around 45 watts! Like I said it tuned very well and very fast. No lengthy searching every! 43 ft DX Eng vertical tuner mounted at vertical base, short wired tuner to antenna, 20 - 32 ft radials (more and longer to be added in spring) it worked great for a year and a day. The tech worked with me through the relay tests and codes and all was as per spec, it just doesn't load, radio internal tuner tunes the antenna but also the coax, not as good as just tuning the vertical. Thanks for answering, I do understand about high out-of resonance voltages, just hard to believe with 45 watts and quick reaction that it would damage it! Like I said they have had it since Sept 7th 2021 and no response from them, NOT looking for free just want it fixed or replaced at a cost OR maybe the 998BRT, 73 and HAPPY NEW YEAR de RON K1VSC first licensed in 1961 as KN1VSC, then Tech, Gen, Adv, Extra. 100% Disabled Vietnam Combat Vet 67-69

Hi, First timer here....I have been using an MFJ-998 legal limit autotuner for a few years, but only on my Icom IC-7300. I'm using the Custom cable for Icom and it works fine, when depressing the Tune button on the 7300 all is good. I recent brought my Kenwood TS-590S rig out of the closet and connected it up to the 998 with the Kenwood cable. I set up the 998 for Kenwood from the setup menu. However the tuner from the radio operates when pushing the Tune button, as if the MFJ isn't even there. I've googled this issue and have seen a solution by changing a resistor in the MFJ. Before I do that I'd like to hear if anyone has had this issue and what was the solution? If no solution, then what was the work-around to get the tuner to function. Thanks in advance for your help. I am posting this in both the antenna tuners group and the TS-590 group. 73, Mike K3FH

Hi all, I have a MFJ 994BRT 600w remote antenna tuner up near the feed point of my 80m horizontal loop. I have about 5metres of home brew open wire feedline from the tuner to the antenna. It works great on all bands from 80m to 12m, getting 400w out. But, on 10m I can only get about 250w output from my Icom IC-2KL with the 80m loop antenna. Can anyone shed some light as to why I don't get 400w out on 10m? My guess is that the antenna and open wire feedline impedance at 28Mhz is too high, but would like a second opinion!!! Regards Rob VK2VH

Where is the [ANT] button? From the manual MFJ-993BRT Version 1A "Delete Entire Antenna Memory To delete the entire antenna memory turn off power to the tuner, and then press and hold both the [TUNE] and [ANT] buttons while turning the power back on. Press the YES [C-DN] button to delete the antenna memory or press the NO [L-DN] button to cancel. Release the button to resume normal operation." bud N0IA Lakewood, CO

Selling is allowed in this group for ham radio equipment only, and at least one of the items for sale must be related to the purpose of the group. We require that anything being sold here have a price with it. So "make offer" or anything like that will not be an acceptable post here. Please indicate if shipping is included, otherwise leave it out. Also, please indicate the general location of the equipment for sale, so others will know if it’s within driving distance for them, and if you're willing to meet someone X miles away from that location. If you have any information about the item, please add it, as it will make it more likely that it will sell. Just list similar to the following. This was a suggestion for the SWAN-AMATEUR-RADIO group. Just replace the Swan item with one that would fit the purpose of this group: Swan 350D, great cosmetic condition, may need new final tubes since output drops somewhat on 15 and 10 meters. Model 117XC AC power supply included. Asking $325.00 OBO. Located near Charlotte, NC. Will drive up to 25 miles from Charlotte for pickup or delivery. Call 444-444-4444, or email hamoperator@....

This isn't a poll as much as a discussion on what YOU use and WHY you use it. For the sake of discussion the word "tuner" means an impedance matcher, used at the antenna or at the transmitter end of an antenna feedline. (We're not trying to discuss which brand is better than another.) Do you use a manual tuner, an automatic tuner, or both (depending on certain criteria)? I haven't used a manual tuner for several years now, but I have a few of those, and two auto tuners. I prefer the auto tuner by far for the ease and speed of getting my parallel transmission line and antenna system tuned to match the transceiver. What I didn't like about the manual tuner is how long it took to tune to a frequency. Of course, having a chart of frequencies and corresponding tuner settings cuts down on the time needed to tune a manual tuner if you've recorded those before. And if you use a computer or even a phone, you could use a spreadsheet to record those (even a free online one from Google) and sort by frequency and band to keep things in order. I know many years ago when I operated tube radios I didn't drop the power level to tune, but I had a home-built Pi-network tuner with a roller inductor and never had any arcing in the caps or inductor. It did the job. I can see an advantage of a manual tuner besides cost--there's less to go wrong. Instead of a bunch of switched-in caps and inductors with relays and some small "computer" chip to figure out which ones to switch in to make a good match, you have a handful of components and perhaps a transformer or balun for use with a parallel transmission line. If I decide to hook up my linear (I'm not a person who prefers them over a barefoot ~100W radio), I'll switch to a manual tuner because that's what I can afford. The better brand auto-tuners for high power cost a lot more than I can justify paying for, and the lower cost ones sometimes seem to be problematic. I have a roller inductor legal limit tuner I can put to use, and if/when I do, I will make a frequency chart to make tuning a faster process than starting from scratch. Donald -- AD8DY Formerly KJ3I ---------------------------------------------------- Some ham radio groups you may be interested in: /g/ICOM /g/Ham-Antennas /g/HamRadioHelp /g/Baofeng /g/CHIRP https://rf-amplifiers.groups.io/g/main

Am I making it through? Jim - K5LAD ------------------- Growing old is like being increasingly penalized for a crime you haven't committed. -- Anthony Powell --------------------------------- Visit my web page at: www.hayseed.net/~jpk5lad/ ============================= Virus-free. www.avast.com

OK, I get posts of new subscribers. But, so far, I've not experienced any traction of postings to the group. Am I subscribed? I would hope so! Dave - W?LEV -- Please join me. Dave - W?LEV

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Hi I have the Dentron 3000 atu one of the black leg drop since the screw missing under [4 leg ] Any one know the size where to buy it Thank you Elan ea5iwt/dl9fcc