I've owned an AT-200Pro for well over a year and recently acquired an AT-1000Pro. I used the AT-200Pro primarily with a FT-857D and later/now an IC-7000. I am now using the IC-7000 with the AT-1000Pro with an AL-82 in the middle. I do NOT run the AL-82 above the power ratings of the AT-1000Pro, and DON'T try it! As the radio interface, etc., of the AT-1000Pro is similar to that of the AT-200Pro, I think some comparisons are relevant to some of the reviews here, and since the reviewers mostly do not mention what transceiver, antenna (Z), and/or power level is being employed.
Both the AT-200Pro and AT-1000Pro communicate directly with later Icom radios, i.e. freq, etc., and the FT-857/897. This communication seemed to work much better with the Icoms, AH-3/4 interface, than with the single pin 3 conductor Yaesu interface. More intuition could be gained here by reading up on exactly how these interfaces differ, and all manuals are available online. For whatever reason(s), I found that much less (re)tuning was going on with my IC-7000 than with my FT-857D once the first cleared memories learned the new settings vs freq, both with the 200Pro and the 1000Pro.
Another issue that really comes into play with auto tuners is RFI and currents reflected into the tuner from the antenna/load. Baluns and RF chokes should come to mind here. Ditto for RF not DC grounds. Otherwise, you may want to stick with a manual tuner and avoid RF bites, by not touching the chassis.
Then we have trying to "match" a load that is outside the auto tuner's stated range. This range can really be compressed also by say power levels higher than rated, jumper cables that are the wrong/bad length, i.e. creating a mismatch vs freq, are simply junk from age or abuse, or even presenting an inductive reactance at higher freqs (my MINI-8/U), the list goes on. Here, a measured purely resistive dummy load, an antenna analyzer, and the suspect jumper cable connected in between can be very informative at the freq of interest. Then connect an antenna analyzer instead of the auto tuner, and determine the impedance seen by the auto tuner, of what you're actually trying to match, at the freq of interest. Is it within the tuner's stated impedance range? Don't forget inductance reactance does change with freq. Sometimes a manual tuner, i.e. MT-3000A, can muscle it's way thru transmission line and antenna problems, unknown mismatches, etc., while the well designed auto tuners hopefully just keep the power low while never finding a match. With the manual tuners you may get a chance to hear sizzles, pops, arcs, and/or perhaps watch power suddenly drop to zero on your exciter or amp........$$$sss.
Between playing with auto tuners, and trying to get a good match between exciter and both HF and VHF solid state/tube amps, it's really been an re-education on the importance of good quality transmission lines/coax jumpers, well engineered and functioning antenna systems, etc., things that a tuner cannot really correct. When you read reviews about this/that solid state amp goes into protection early and often, and the amp is being blamed, I'm guessing the amp is just trying to save itself. Sounds like a lot of folks may be running into auto tuners trying to save themselves also, but blaming the auto tuner?
The bottom line is that my both my AT-200Pro and now AT-1000Pro work as advertised, and that once memorized, the AT-1000Pro tune time into my antennas is less than a second, if at all, running 750W CW/1kw PEP. And I have had several jumper cables hit the trash where they belong. Also, as the MFJ-998 appears to be a copy of the AT-1000Pro, yet the MFJ claims to be capable of legal limit, and at nearly the same price, would be informative to see some reviews on the MFJ-998 review thread from legal limit ops. I'm a veteran of the MFJ-989 back when they referred to that tuner's power rating relative to the input power of the EXCITER. Snap, crackle, sizzle, pop.......
As to whether a particular vendor is polite, etc., as a vendor I would politely refer inquiries other than product specific inquiries to souces such as the ARRL Antenna Book, online product manuals, brochures, etc. Let's face it, if you're not up on the basics of station safety, transmission lines, antennas, etc., it might be a good time to delve into these areas, especially BEFORE playing with high power stations, tuners, amps, etc.
And not trying to be condescending here. There's always more to learn about any field of interest.
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