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I have this thing with tuners

My field day antenna tinkering made me realize I have something with antenna tuners. ATU. Antenna couplers. Or remote automatic matching systems. Potato – potato. Tomato – tomato. That doesn’t work when you type it. But you know about what devices I’m talking. It’s the deus ex machina for people with antenna problems. It magically deals with weird impedances, one size fits all antennas, non-resonance – everything that does not present 50Ω to the transmitter or amplifier.

My first HF rig, the notorious TS-850, had an ATU on board. I’m surprised the tune button didn’t get worn out. I had an inverted V dipole cut for twenty meters. That’s the general advice offered to the newbie on HF: twenty is the place to be. Running barefoot with a 25-30 meter stretch of RG-58, and then hit ‘tune’ to get me some contacts on the other bands. Cycle 23 peaked and it worked above 10 MHz. It made the finals happy on 40 but it didn’t bring me much joy. The ATU even found a match on 80 but even a little RF power there turned on the hifi stereo and made the cassette deck play. Cassettes, go figure! That was a scary surprise the first time it happened. On Top Band the ATU didn’t find a match. But the rig’s ATU made the DXCC counter tick on the higher bands.

The more I got into basic DXing (I had yet to get introduced to contesting), the more I learned. I think I read every related website available back then, so to speak. I learned that manual external tuners not only have a matching network but more than often they also have a 1-to-3 switch on board. Since I managed to convince my dad to run another length of RG-58 through the house and between the roof tiles, that would be a nice solution for me: dipole, the 30m vertical I also managed to desecrate the parental lawn with and the homebrew dummy load.

A local ham offered such a tuner. The Kenwood AT-230. I bought it. I used it. It served me well when I was living at my parents. I already wrote a story about this tuner two years ago. It was a nice thing but I sold it a few years ago. At the same price I bought it! I didn’t need a manual tuner here anymore and it was just sitting on a shelf.

I didn’t need a manual tuner anymore  because I bought an SGC SG-230. Somewhere in 2002 I guess, from a UK supplier. Again after much online reading. That thing was and still is pretty expensive so I doubted a long time. But I worked for a living and was still living with my parents then so spending money didn’t really hurt. That thing worked great too (eHam review to testify) and I still have fond memories of WAE CW 2002. Yes I got bitten by the contesting bug by then. I made a temporary 40m delta loop fed with this antenna coupler. Sunrise brought me ZL6QH there, totally impossible before from my parental peanut station. And a bunch of Californians. Those few real DX stations answering my 100W CQ on such a hard band as 40m (little did I know how easy 40 really is) with a simple wire, it was amazing. I still remember the feeling. But contesting is like a drug addiction: you always need to crank up the dose for the kick to remain as intense. A dozen years later, if I don’t work a 120 QSO/hr west coast pile up at sunrise, I’m not happy. So to speak.

Then I moved to here. My own personal contesting ranch. I built my station around a tower and swore by resonant antennas. The SGC coupler was still used to work my first DXCC on 160. Even USA. Again: getting out of EU on 1.8 MHz was a milestone. I even recall a brief experiment with an 80m delta loop here in WAE CW 2005. Fed with the ladder line I now use for field day. But that thing was too big for my taste. And I didn’t get to give it a real test. Now that I looked it up and read it (3830 report), I remember that T-storm. You see, I have always been plagued by the weather.

But then I changed my contesting style to QRO and the SG-230 was useless. We used it in 2006 for the OT1A/P field day activity. It sat in a box for years until I decided to sell it a few years ago. I effectively sold both the AT-230 and the SG-230. Both have served me very well and are really good devices. But they weren’t used anymore. I had always said that a SGC coupler that would take full QRO with the same ease would be a commercial hit. I’d buy one right away if it wouldn’t cost an arm and a leg. In other words: unlike the system that was already available (link).

Then we did some work in the garden and on the terrace and I changed my 80/160m setup. It was time for a big performance jump to increase my contesting fun. Junky needs a bigger shot. I had come up with the plan to make myself such a QRO tuning device that would make a ground plane look like 50Ω on the two lowest bands. To make it easy, I started looking for a manual QRO tuner. High power rolling inductors and high voltage vacuum capacitors are expensive so why not just buy a tuner and motorize the dials? Then a Palstar 1500W tuner presented itself. I didn’t waste any time and bought it. It was a beauty. But:

“Of course soon after the purchase, when sobering up from the rush of having made the deal of the century, it dawned on me. I make many plans yet execute few. I envisioned the tuner packed in the box for a few years and then I’d finally decide to sell it. So I put it for sale online right away.”

I believe this is its new home since then. My gosh, 2008? Tempus fugit indeed!

I’m not sure about the dates anymore but in Autumn 2009 I gave it another go for the low bands and bought an MFJ-998. Yet another tuner! It handles 1500W according to the specs. It wasn’t cheap but not too expensive either. If this black box handled my low band matching needs, the investment was justified. There was no ‘remote outdoor’ unit available like they have now. So I hacked my way through the tuner and ‘remoted’ the tune button. That way the tuner was only inline with the 80/160 GP antenna, out of the shack and close to the feed point in a weatherproof cabinet. Still I could switch it on or off from the shack and had remote access to the tune button. Straight out of the box, I drilled a hole through the enclosure to bring my remote cable inside. Warranty void if buyer drills holes? I had mixed feelings about this one. It can find a match near resonance but it can’t handle really tough stuff. It was nice to use my CW tuned 80m antenna in the SSB part without fiddling with the wires. But it couldn’t get this thing to work on 160. So in the end this one too got an early retirement. I decided that the best match was resonance so I redesigned the antenna with two resonant wires, the 160 part being linear loaded. Once again I was able to find a buyer and cut the losses. But yet another tuner that cost me some money.

Since then everything was quiet on the tuner front. I settled for matched antennas. But one day someone offered an AT-230 for sale. Like the one I bought. Like the one I sold. The ad said ‘like new’. Do I need one? No. But I had some regrets about having sold it. It was purely a case of nostalgia. The price was the same as the one I bought a decade ago and as much as I sold mine for. So buying this one would financially restore the balance to the 2001 situation and would put one AT-230 back on the shelf. It has been there for almost two years, only to sense some RF last week in my attempted field day.

For this field day experiment I decided I needed a ‘smart tuner’. I evaluated all other options yet settled for an automatic antenna coupler. Yes I had one like this, maybe the best in its class. Yes I sold it because I didn’t use it anymore and thought that resonant antennas would be the way to go on field day. The SG-230 is still available but it costs a lot. But there is its brother that comes without weatherproof enclosure. The SG-239. It’s said to be the naked ‘230. You probably won’t believe it, but once I bought TWO of these at once. It must have been 2005 or 2006. My guess is 2005 because in January 2006 I bought an amp and took the QRO route in contesting. So why still buy 200W thingies then? I know because it’s the only two years I visited the notorious Friedrichshafen ham fair: 2005 and 2006. A major German dealer offered them at a bargain price. I think it was 230 Euro or so. Maybe less because I seem to remember I asked for a discount if I bought two. Back home I managed to sell one right away. No profit taken, as a close ham friend bought it. I bought a plastic food container with rubber seal to put the other one in. I remember I drilled the holes and put bolts with wingnuts through them as the wire terminals. I vaguely remember someone picking it up in the plastic container. So I must have sold it before the enclosure got finished. Geez, I really start a lot of projects and finish only few. And I have this buy-sell thing with tuners!

Anyway, field day. Smart tuner. Price difference between SG-230 and SG-239 is about 200 Euro. For a piece of plastic? I had a fitting enclosure in my huge stock of parts. Something I bought a long time ago for who remembers what project. Possibly a K9AY RX loop. It had some holes but I put aluminum blank panels inside, fixed with pop rivets. I sealed these from the outside with silicone. Make sure you have ‘neutral’ silicone because the rancid smelling vinegar based silicone is very aggressive to metals. Don’t ask me how I know. It makes brass turn green overnight.

So with the regained AT-230 and the new SG-239, I once again have two tuners. A classic manual tuned device and a remote automatic antenna coupler. Of the latter I still say: too bad SGC doesn’t make a real QRO model. The SG-230 and SG-239 are great tuners, and I trust them more than the MFJ-998 that I have used myself with mixed success. The reviews of the MFJ-998RT outdoor model aren’t unanimously positive either. All the rest is just very expensive. Quite frankly right now I don’t have the need for such a device either.

Me thinks I should leave tuners alone for now.

3 replies on “I have this thing with tuners”

Long time very happy camper here using 2 SGC230 units. I agree with you on your observation about QRO autocouplers, but I’m afraid there’s a higher order relationship between handling power(especially under severe mismatch conditions) and selling price… I remember back in the early nineties when I started working on my first job as an RF project engineer… job at hand was the extension of a HF TX site for our Belgian MoD near Kemmelberg. Mostly full-sized big wideband biconical ground-mounted thingies with huge radial systems, some BIG log-periodic rotatables and one 23-ft marine whip which was to serve as a backup, fed through this monstrous Harris 1kW autocoupler. 1kW 100% duty cycle that was… Back then it cost well over 10k EUR. I’ve seen it popping up for sale recently, alas without the necessary external control unit and no manual was available. As for the JC-x line of tuners mentioned above, although they look interesting at first glance, they do raise some red flags here: no manufacturer info, no direct contact details, only available on online selling/auction sites, some iffy specifications, no downloadable data sheets, no online reviews apart from the ones on the selling/auction sites… I don’t know. If it sounds to good to be true….. but then again: I’m ready to stand corrected when proven wrong with hard engineering data 🙂

73 es gud dx de ON4WIX

I’m using the JC-4 coupler now. It’s rated 1KW pep when used with antennas long enough. The manual states that very short antennas on lower bands or large impedance mismatches puts stress on the components and reduced power is advised.

At present time I have the JC-4 in a symmetric setup feeding a 600 Ohms open wire line to a 2 x 23 meter dipole. The couplers handles all bands just fine from 160 to 10 meters, no gaps, zero problems. I’m working with the full load of my Acom 600S solid state linear amplifier. Never had problems. The tuner coops very well.

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