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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
KK9H Rating: 2020-05-23
Works well, but had the same stripped screw issue Time Owned: 3 to 6 months.
Well, I didn’t have a completely bad experience like the previous reviewer, but my 998RT also had two stripped screws holding on the plastic cover. Like most reviewers I also carefully removed the cover to check the contruction inside and I’m happy to report that the build quality looked very well done. For many years I have used a Drake antenna tuner with my 130 ft. inverted-L antenna on 160-40 meters and always wished I could automate the antenna tuning process since the antenna feed point and tuner are located a fair distance from my operating position. I had been skeptical about the MFJ automatic antenna tuners due to concerns cited in the reviews of MFJ products, but I’m happy to report that my 998RT works perfectly. I have left every setting at “factory default” and my 998RT successfully finds a match of of under 2:1 SWR on 160, 80, 60 and 40 quickly and smoothly. Basically, it works just as it’s supposed to. The only reason I gave it a 4 due to the obvious stripped screws that would have been easy to remove and replace during the manufacturing process. It should not have been shipped from the factory that way so quality control remains the be MFJ’s main issue but my 998RT works just fine.
K7NNV Rating: 2020-05-23
Horrible Quailty Control if any at all. Time Owned: 0 to 3 months.
I just received the MFJ 998RT that I ordered from HRO this morning. As usual with any MFJ product I do a quality control check prior to putting it in service. First, 2 of the screws holding the cover on were stripped out and I had to use a pair of long nose pliers to pull them out. Once I removed the cover it was quite obvious that this unit was a refurbished by the finger prints and the remnants of a removed tag.
Then the other shoe dropped, capacitor C203 had pulled away from the circuit board and there was no way to get to it to re-solder it.
Somehow I knew better that to purchase an MFJ product but they are the only affordable game in town.
NI0C Rating: 2020-03-18
Tunes reliably and quickly Time Owned: 3 to 6 months.
I use this tuner to match a N6BT Bravo V8 vertical dipole antenna on 40, 30, 20, 17, and 15 meters. Using a tuning power of 13 watts from my Elecraft K3, the tuner achieves a very fast match with a final SWR of no more than 1.5:1.

The feedline is 300 ft. of high quality coax, and I use a 1:1 common mode choke at the tuner input, with DC power for the tuner supplied through the feedline.
I run about 500-600 watts, using an ACOM 1010 amplifier.

The unit is mounted with U-bolts on the antenna support. I was not convinced the supplied gasket in the enclosure cover would provide adequate waterproofing, so I supplemented it with a combination of coax seal and electrical tape around the top and sides of the enclosure. Since there were no weep holes in the enclosure, I omitted the bottom row of screws. So far, so good in heavy rains and some snow this past winter.

The unit has a nice set of controls and a display panel that I wish were visible with the enclosure all buttoned up and sealed; however operation is so automatic, it really only needs to be setup once. It works for me!

I previously used a LDG RT-600 (600 watt remote tuner) that was not nearly as satisfactory and had some issues with tuning. The MFJ unit is much faster and dependable.
W2NER Rating: 2019-09-03
wonderfull Time Owned: 3 to 6 months.
I was very sceptical when I purchased this and the only reason I did was I had the 998 in my shack which performed great. So, now that I have put it through the ringer for the past 4 months, I have to say I'm VERY pleased. Works great and no more RF in the shack! Its been a pleasure to use and I have had MANY tuners (check my QRZ page) and I have to say this is the BEST bang for the buck. I have put 1200w into it and I have had ZERO problems. I know its got some bad press but I think this has to do with problems from a user view point. If you expect this to handle 1kw and tune as well, get your head out of the clouds because thats not realistic. This has been the best money I have spent in some time... I use it on a inverted L made from a 30ft flag pole. Handles every band with no problems at all.....
WR0F Rating: 2019-04-05
DOA on MFJ 998RT Time Owned: 0 to 3 months.
We received our tuner last night and ran up to Home Depot in get U bolts for mounting on 1.9 od pipe . We got it mounted on the pipe and hooked up feedline . Then it was time for the 13.8 volts

We plugged in Bias Tee in with dc cord after hooking up antenna with tuner. The dc cord which is non fused started smoking ,Very bad start on a new antenna tuner .

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Earlier 3-star review posted by WR0F on 2019-04-04

Tuner came with no owners manual .Note in box manual can be printed online . What if you do not have a printer ? and no u bolts mounting hardware to mount to my 1.9 od pipe in the ground
W4IEE Rating: 2019-04-05
Update - working fine Time Owned: 3 to 6 months.
This is an update to my Jan 9, 2019 review.
I now use a long wire different from previous one. Wire goes vertical about 15' at back of house against a fiberglass mast then out about 70' slightly sloping upward to a pine tree, at about 40' the wire comes down the side of the tree thru an insulator for about 30'. Total length of vertical and horizontal wire is ~115' I have a ground system around the house with 6 rods inter connected with #6 wire and connected to electrical box bonding point. The ground and antenna wire terminate at the tuner sitting on the ground in a covered plastic box. Also have a lightning arrestor and line isolator in the box. The tuner does a good job 160-15m with SWR below 1.5:1 but can't tune 12/10m - wire too long I suspect. It handles all the power I can give it from the KPA500. Aside from the poor assembly noted in previous review, the tuner works well.
VK3BZF Rating: 2019-01-14
Reservations Time Owned: 0 to 3 months.
I am generally happy with the unit. It handles the legal limit well in VK. A few major frustrations however are that one can’t operate or see the control panel as they are underneath the lid of the RT unit at the feed point. These controls and data screens would be so helpful to have in the shack! One amateur has suggested cutting a hole in the cover of the mfj998rt which would be highly impractical and damage the device. Does anyone know how to easily bring these switches and data information screens into the shack?
I have checked with mfj but they don’t seem to make such an item except to purchase an Mfj998 shack version (which displays this data and has the controls but this defeats the purpose of having a quality feed point tuner like the mfj998rt not to mention the expense. Doe any one have thoughts as these would be most
welcome. I am happy if you would please email me your ideas to peter.wilson.mapss@gmail.com 73’s Peter vk3bzf (former Vk3mow).
N4MIT Rating: 2018-09-05
Unreliable at best Time Owned: 6 to 12 months.
After the second failure I returned it for replacement just to find out they don't have any in stock. It is very unforgiving and when the relays fail it burns a hole in the circuit board. The relays are just not heavy enough. I have never been able to put 1500w to it even at 200w it struggles to keep the smoke inside.

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Earlier 3-star review posted by N4MIT on 2018-02-20

It works great for SSB/CW but it doesn't like RTTY or FT8. The SWR creeps up the longer you transmit even at 200w from my FTDX5000MP. I kinda expected it not to take 1500w of RTTY but it should handle 200w for more that 15 seconds.
K4HYJ Rating: 2018-06-26
2 years and no problems Time Owned: more than 12 months.
I bought mine from an SK over 2 years ago. It was still in the box and so clean that I wonder if was ever installed. I installed it outside right at my foundation where the coax went through. I use 2 dipoles (identical) oriented 90 degrees apart. They are 15:1 on 15 and 30 meters (50 ohm). The MFJ unit has no problem tuning them.

I usually run 100 watts, but have run 1500 watts from an AL-1200 with no issue. It is important to install per manufacturer. It needs a separate ground wire ran to your station/antenna grounding system - don't just rely on your coax shield. Also, I use the bias tee for powering the unit. Because of a long coax run, I make sure I feed the bias tee with 13.5+VDC. Another item to note is to wait 6 or 7 seconds after turning the unit on before trying to match an antenna. Similarly, when power cycling to touch up a tune, wait several seconds after turning the unit off before turning it back on.
N3PS Rating: 2017-06-13
Overall Happy . . . Time Owned: 3 to 6 months.
I have not been a fan of MFJ (previously a DOA antenna analyzer and a stray nut found rolling around the inside an Ameritron amp) but needed a remote ATU solution for my 135' end fed antenna used for 80m and 160m. Currently, the 998RT is the only product capable of handling the full legal limit.

Overall, the unit has worked as advertised.

My only complaints:

* The unit requires a minimum of 20 watts to recognize transmit frequencies on 160m (10 watts sufficient on all other bands).

* When mounted vertically, and to keep the internal display right side up, the cover is upside down.

* The unit lacks range to tune up low impendence situations (< 50 ohms). In order to get the ATU to tune up my end fed on 160m, I eventually had to place a 1/4 wave matching section of coax between it and the antenna.