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Reviews For: MFJ-998RT Remote Auto Tuner, 1.5 kW, 1.8-30 MHz

Category: Antenna Tuners/Matching Networks

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Review Summary For : MFJ-998RT Remote Auto Tuner, 1.5 kW, 1.8-30 MHz
Reviews: 50MSRP: 769.95
Description:
An MFJ HF tuner (160 M-10 M), capable of 1.5 kW of power SSB and CW. It is an external tuner and can be installed at the base of the antenna, which yields better results than with the tuner in the shack. It goes well with the Ameritron amps: ALS-1300, AL-80B, AL-82, AL-1200 and AL-1500 legal limit amplifiers. It weighs 9.5 lbs and has an ABS plastic cabinet and stainless steel metal chassis. It measures 13.75x6.75x17.5". Matches instantly impedances from 12-1600 ohms and includes 20,000 virtual antenna memories. Has one coaxial antenna and a binding post for end-fed long-wire antennas. Upgrade firmware via a serial port. Includes a one year warranty.
Product is in production
More Info: http://www.mfjenterprises.com/Product.php?productid=MFJ-998RT
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
24503.4
W5JO Rating: 2013-08-30
Would recommend again Time Owned: more than 12 months.
After owning and using this tuner with everything from 5 watts to 1500 PEP I still like it. It has performed flawlessly and tunes my antennas properly

Remember that if your antennas complex impedance is out of the range of the tuner it won't work but in my case everything is cut and installed to provide the proper operational ranges so the tuner works as advertised. The unit will match all bands using my 1/4 wave inverted L for 160 meters except 80 which is out of the match range specified by manufacturer specifications.

Keep in mind you are dealing with a computer. If, for some reason, the memory is scrambled by a power flash or surge, it will cause problems. If you protect it as best possible from surges and isolate it from lightning then you should not experience major trouble. I have a relay that grounds my antenna system between it and the antenna connector of the tuner and thus far I have not had a disastrous lightning strike induced problem. Also I live in a rural area where power flashes and surges are common and proper protection on the power source of the tuner has prevented component failures but it will lose memory and it sometimes won't tune. So I pull the cover and do a reset and it starts right off.

If you have tuning problems, follow the reset procedure and it should work fine. The manual has several test procedures listed so, if you have trouble, follow them. My experience with MFJ customer service has been very good by email. They are very willing to help you isolate problems and give suggestions as to what you can do to fix the problem. I recommend the unit.
TF3ARI Rating: 2013-05-21
1 month old and still 100% Time Owned: 0 to 3 months.
Little add to my old review.
Tuner is now over 1 month old, I use him with up to 1 Kw daily and down to 1.840 Mhz from 6 meter and tuner still working 100%.
As many hams say he works only 1 to 5 days so there are good tuners out there or used as manual explain it should be or MFJ have fix there problems with it.
73
TF3ARI
DL4CW Rating: 2013-01-27
forget it! Time Owned: 6 to 12 months.
Part 3 of the story, or how it all ended. In brief: After the device had failed for the third time I finally demanded a complete refund, which was granted by the dealer without any further inquiry...

The tuner was meant to replace a 100W autotuner (which btw did its job flawlessly for over 8 years at the feedingpoint of a 33ft vertical in my backyard). I replaced it with the MFJ just to be able to run legal limit power.

The first time it failed after 2 months with the same symptoms as described by LA5HE. Since it still was covered by warranty, I had sent it back to the dealer and it was returned to me after 6 weeks, a chip of the divider chain as well as the PIC chip had been replaced.

After successfully testing the device I put it back into place where it lasted - I couldn't believe it - JUST FOR FOUR DAYS - before it showed the same symptoms again. I again had to return it to the dealer. The PIC chip was gone once more, this repair took another 7 weeks.

After that it worked for about 4 months when I first noticed that the SWR would suddenly run bad on certain bands when increasing tx power beyond 25-30 watts. Leaky caps in the LC network this time? Anyway, it's history.
RK3TD Rating: 2013-01-10
Good, but not great Time Owned: 0 to 3 months.
By paying attention to the previous reviews, I first carefully examined the new product. The funny thing is that the PL-connector MFJ-4117 missing one screw and nut jumped inside device. Restoring the MFJ-4117, I opened the main unit and looked him in the presence of poor quality soldering or other mechanical problems. All appeared normal. I did not change the default settings.
I use a device with an GP. Antenna height of about 7 meters (24 feet). The antenna has a few radials also up to 7 meters. The device is ideal works in the frequency range from 7MHz to 25MHz.
At 28MHz tuner refuses to find a normal SWR. It works more than 20 seconds, and in the end - a mismatched antenna on 10 meters. This seemed strange to me. However I found a way out of this situation: device has good matching on frequency 28.7-28.8. In the CW TX (28.0XX) station of this matching is enough.
Few words about 3.5MHz: Yes, it works, but the effectiveness of 7-meter GP is very low. So talking about the normal long distance QSO on this band is not necessary.
In general, the device I'm satisfied. But given the weaknesses identified during the first examination, and work on 10m, can not put the highest rating.
W7DAU Rating: 2012-12-03
Call it the Gambler Time Owned: more than 12 months.
I have had the unit for about a year and a half. I would not recommend it to anyone for purchase. I call it The Gambler because sometimes it works and sometimes it doesn't. I am using a 43 ft. vertical over an excellent radial system and Andrew LDF4 for the transmission line. And a ICOM 7000. Using this vertical it requires using some kind of antenna tuner so I depend on this unit. When I change bands, 75, 40, 30, 20 meters I always have to turn it off, let set for a few seconds, and sometimes it will tune. Often I have to do this multiple times to get it to tune. This is the reason I call it The Gambler, you never know the outcome. When it does work the VSWR can be anywhere between 1.7 and 4.0. I am not at all satisfied with the unit. Right now I live in the city and am going to set up my ICOM tuner at the base of the tuner. Will have to run control line but it will work every time. MFJ is loosing it when it comes to reliability. This is the second piece of equipment I have purchased from them that was inoperative.
OT1A Rating: 2012-11-26
OK if not too difficult Time Owned: 0 to 3 months.
First of all : the points are given for my own box, not to the general product, nor MFJ customer handling. My box is used as a portable solution during a contest, so no suffering of rain and wind during longer periods.

This is written after about 1000 Q's on the low bands in both CQWW contests and always with about 850 W delivered by an Acom1000. I didn't check the ability to handle legal power, and I will not try it...

Before ordering this one, I've sent mails to most of the people that made a review in this chapter. It seems that there are serious problems with the first series, especially those boxes sold in Europe. QST did a review and mentioned an upgrade by MFJ in particular around the PIC-circuit. This was generally the mean complaint of the owners with trouble boxes.
In order to avoid this, I ordered directly to MFJ ** cut / a too long story about customer (dis)satisfaction, published in detail on my blog ot1a.blogspot.com ** and two days later at DXEngineering. Perfect order handling by DXE.

I opened the box : all solderings in good shape, nothing bad to mention.

Do not expect a wonder box. It tunes something that is tunable, but nothing more. I tried a 30m longwire with elevated radials : ok on 40m and 160m but no tune on 80m. Just to give an example that you can't play a random game.
But when correctly used it is a pretty nice tool.

My only complaint : the connection for the mean wire is on the backside and you have to pass an opening made in the metal (earth) part. There is no isolation foreseen. I've had sparks probably caused by a contact between the wire and earth (due to the wind). A better design for this is preferable. I will make a solution by isolating the hole in the metal part.

Another difficult point is the collaboration between the TX and tuner at the start of a tuning : my Yaesu sees a bad swr and goes into power protection, while the tuner needs power to perform tuning. I've detected that placing the TX into FM-mode and quickly changing the power level between 0 and 30W gives the best and quickest result.

For this reason I can't give a 5.

73s Ken
ot1a/on4ccp
G4GED Rating: 2012-11-24
Glad to be rid of it! Time Owned: 6 to 12 months.
This is my 2nd and final eham review for this device. It never worked correctly from day 1 and needed a dealer repair when it blew a voltage reg chip. Over 11 months I tried all the various optional settings but it would rarely tune reliably and always required several off/on power cycles when changing bands. I've just traded it in for a Palstar HF-Auto which so far works perfectly. Although it's not so elegant tuning an antenna from the shack as against tuning at the feedpoint, since my feeder SWR is not too bad on any band, I can live with it. As another reviewer has said, if a "quality manufacturer" could take on production of a similar remote device, then it could be a huge success. As things are, I'm very happy to be rid of it!
K1BZ Rating: 2012-11-11
BEWARE ! Time Owned: 0 to 3 months.
The 1st one had a wire broken off the mother board to the SWR daughter baord. The dealer quickly replaced with a 2nd unit. I ran several days of testing and couldn't get the device to maintain a match on most bands. It kept going into the retune mode. I returned the device and installed a manual tuner in the shack. A remotely powered autotuner at the end of a long coax line is something the amateur community sure needs, at least I do, but I certainly can't recomend the '998RT.... MFJ should go back to the drawing board.... /DL
W4YN Rating: 2012-03-15
Acceptable Time Owned: 0 to 3 months.
Worked out of box for me. Only issue I have is the rig I use most of the time does not like even moderate SWR and shuts down while tuner is self tuning.
The other issue is on another rig the rig output with out linear is 5 watts which is not enough to start tune process.
K6QT Rating: 2011-11-28
Wonderful external antenna tuner! Time Owned: 0 to 3 months.
So far only owned for a few days, but works better than an antenna tuner in the shack. Would recommend. Will post an update after I have had this for a while to give a more thorough review. It's really too new now to give a good review.