| N1JDH |
Rating:      |
2021-12-15 | |
| Excellent Remote Tuner |
Time Owned: more than 12 months. |
I purchased a 994 BRT 2 years ago and it has provided very reliable service. I use it at the base of a home brew 14.5 meter vertical antenna. It is fed with 150 feet of Davis RF Buryflex. It has provided very reliable service, both in barefoot mode with my Flex 6600, and with my ALS-606 Amplifier at 600 watts. Occasionally I have to power cycle the unit to get a better SWR. Although I have never had it provide an SWR greater that 2:1; I prefer around 1.5:1 at most when using the amplifier. I am a retired communications engineer, and I find this a very good value for the price. When tuning the unit, use 15-20 watts; this is made clear in the documentation. Based on my recommendation a couple of ham friends also bought units. One of them complained to me it was crap as it would not tune on 40 meters or below. I went over to look at his setup: He was using a single ground stake on a vertical wire only 7 meters high in a tree. No tuner is going to perform well with a vertical antenna that is too short and with no real RF ground system (a ground rod is not an RF ground system). I brought some wire over and made an inverted L for him 7 meters high and 20 meters long. Laid down four ground radials 10 meters long. The tuner worked fine. My buddy's response was that it was still crap and I was "cheating." I spent many years designing and building antenna systems for military and commercial applications, I'm always amazed at how many hams say something is crap when they don't follow the instructions or think something can perform magic. I guess I don't know what I'm talking about because I'm only a "general" and he is an "extra."
Update: I've used this unit now for over 2 years and it continues to work great. It is mounted inside a weatherproof enclosure, so the unit itself is not exposed to the elements. I do this because the location of the tuner is such that it is exposed to saltwater spray. Any metal quickly corrodes in this environment. Even in the enclosure I have had problems with degradation of some electronic devices, but not this unit. |
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| MM0IGN |
Rating:     |
2021-10-23 | |
| Not perfect, but good. |
Time Owned: more than 12 months. |
When I got this ATU, it didn't work at all. In disgust I put in the pile of broken things for about 2 years. Eventually I took apart to find the grounding terminal was very loose.
After mending this, it is actually a very good and very convenient device. I have had numerous 59+ reports driving a simple 9 metre vertical, grounded to 32 radials.
It is the closest thing I own to a 'magic antenna' that just does everything, and with very little compromise.
If you don't mind very likely having to finish part of the assembly, it is possibly one of the best things you can buy. |
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| K8JHR |
Rating:      |
2021-09-05 | |
| Sweet. Super easy and reliable. |
Time Owned: more than 12 months. |
I built a dual-band, two element Inverted-L antenna system for another ham and we installed this at the base/feed point. We installed 20 ground radials in his small city lot. The goal was a full-band antenna on both 160 m and 80 m that would accept modest power from his 600 watt solid state amp. We hid /protected the unit from bad weather, and marauding children from the neighborhood, in a fiberglass fake rock from the hardware store (as described in my article published in March 2016 QST Hints and Kinks column.) A design requirement is easy of deployment, ease of use and ease of control from the shack, as this is a remote tuner located a good 80 feet from the operating position. The antenna has a 66 ft element on 80m, and approx 125 ft element on 160 m. Both are configured as Inverted-L.
The operator is extremely pleased on all points. It is super easy to operate and trigger tuning from the shack. It has been extremely reliable and tunes both entire 160 meter and 80 meter bands, and accepts modest 250-500 watts of power without breaking a sweat. He does not run a full 600 watts, solely to be conservative and not stress the station - which I think is key to reliability and clean signals. The fiberglass landscape feature provides weather proofing and visual coverage so works well, out of sight and out of mind - and it has provided reliable service for at least two years without adjustment, resetting, or other maintenance. (Now if we can just get the squirrels to stop gnawing on the support ropes, it would be perfect!) BOTTOM LINE - easy to install, easy to use, reliable over time. We are both pleased - I am especially pleased as it was my idea! K8JHR |
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| WB1D |
Rating:  |
2021-03-08 | |
| Tuner is unable to tune with 600 watt linear. |
Time Owned: more than 12 months. |
I purchased this thinking that it would work with an ACOM 600S linear running at 600 watts. It does not work. After tuning the antenna with the MFJ tuner, running 100 watts or less, and then increasing the linear power, the linear just shuts down and gives a high SWR fault. Also when operating at 100 watts it can find a relatively good SWR of 1.5:1 and suddenly try to re-tune without warning, sometimes unsuccessfully. After many calls to MFJ technicians, I was unable to solve the problems and the reset procedure involves taking the unit apart, finding some poorly placed buttons, and having to press three simultaneously. Pretty much a nightmare. Not recommended. I run 200 watts on a sailboat in the summer with an SGC tuner and it works beautifully with none of these problems.
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| W4IOA |
Rating:      |
2020-09-28 | |
| does it's job well |
Time Owned: more than 12 months. |
September 2020.
After 3 years this unit has never failed to deliver and it still does the job. Snow, deluges, and blistering sun has not been an issue whether I'm running digital or SSB, it always tunes the antenna. I have it set upright on aluminum stock pounded into the ground and it sits right outside in the weather. And I've hadn't needed to reset it since I last reported. Great product and has been worth it's money to me.
2017
I have this at the base of a flagpole antenna. 150' of coax feeding the antenna and the tuner works. There is a bit of a learning curve and the instructions are not as helpful as they could be so I am rating it a 4. Haven't needed to crack open the box, I installed it at the base of the antenna in a vertical position high enough that the bottom is 8" off the ground. Been through some typical mid-south squalls and lots of driving rain without a problem. I think if they improved the instructions and clarified on how to properly tune it there wouldn't be problems. 40m was the only frequency I had any issue with but after a reset I got it up and going.I'll come back in a year and give another review. |
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| N4ECW |
Rating:      |
2020-06-16 | |
| Revolutionizes Portable Antenna |
Time Owned: 0 to 3 months. |
I bought the MFJ-994BRT to test on a Transworld Antennas structure to eliminate the TW center section switching array. Additionally, if successful, it would eliminate the need to interchange individual TW2010, TW3030, TW4040, TW6060, and TW8080 center sections. I am happy to report that the experiment was a resounding success.
The unit tuned all bands from 6 meters through 60 meters near perfectly (i.e., 1.5:1 or usually much less). The MFJ-994BRT struggled to tune 80 meters on the small structure; but, would generally get the SWR down to slightly below 2.0:1 between 3.5 and 4.0 MHZ.
I recommend first tuning the unit at about 20 watts of transmitter power, checking at 100 watts, and then going to full power. I kept my output power at 500 watts or less without any difficulty.
When the HF bands were open, I had no problem making contacts and had great signal reports including occasional contacts with Germany, Spain, and France.
Contacts on 40 meters and 80 meters were at least as good as using the TW4040 and TW8080 center sections with similar power outputs.
Upon retirement, I moved into a condo with serious restrictions for hams. I used the set up on the concrete area just outside my screened lanai and also inside my screened large porch. The results were simply amazing.
The condo association president and the property manager expressed appreciation that the set up was fully portable. I actually set it inside the screened porch when not being used.
I chose this L-network tuner over a PI network tuner (i.e, ICOM AH-4 and Yaesu FC-40) for its ability to deal with a higher output and higher mismatches. However, a PI network tuner is faster until the L-network tuner places your usual frequencies in its memory bank.
I'm unable to speak to the unit's ability to tune various lengths of random wire. Other reviewers will have to speak to those type installations.
I noticed that when the Bias T is placed too close to your transceiver that it tends to give off a 1-2 S unit hum. It's best to place it at least a couple feet from the rig even though it may be slightly inconvenient.
Before you e-mail and ask: you can either use a coax pigtail on the UHF port of the unit or remove a TW array box from its center section and attach a wire to the top post and the bottom post and then attach both to the to the ceramic insulator where a random wire would ordinarily be placed. I opted for the latter to avoid the possible need for a 4:1 balun.
D.M. Barrett
N4ECW@arrl.net
Former owner and developer of Transworld Antennas
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| WA8ZIP |
Rating:      |
2019-07-23 | |
| Very cool gadget... works well |
Time Owned: 0 to 3 months. |
I had been frustrated with the very narrow bandwidth on my 160 and 80m loaded dipole with high SWR near the band edges and figured a remote tuner would be a good solution. After receiving the unit from HRO, I opened it up and did an inspection; all looked good, although I did snug up the external ground terminal. I also discovered that my shipment incorrectly included an MFJ 4712RC remote antenna switch instead of the 4117 BiasTee Power injector. The 4712RC will also inject DC power into the coax so I was able to proceed with checking the tuner without a problem. I contacted MFJ and they promptly sent me the correct part (looks like they are basically the same part, just labeled differently).
After the inspection, I setup the unit near my radios so I could check things out before heading outside for the installation. I was very impressed from the moment I applied power, some RF, and heard the relays click away.
The unit tunes quickly to find a good match and remembers those settings to tune almost instantly when returning near a previously tuned frequency. It’s easy to bypass the unit by turning off the DC being fed up the coax. I spent 2 days trying many different bands and power levels up to 500 watts CW and SSB from my little Ameritron AL-811 amp. Just for fun I tried feeding a 3 element 20 thru 10m yagi some 40m RF and the tuner quickly found a match to make the transmitter happy. After all looked well I took the 994BRT to the roof and installed it on a chimney mast with a good earth ground and a short jumper to the antenna.
This is one of the neatest ham gadgets I have seen. It’s not exactly built like a tank, but the sealed plastic enclosure seems durable and up to the task. It’s lightweight and had a reasonable price. It’s well built and works great, an easy “5”. DE WA8ZIP |
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| KG9H |
Rating:      |
2019-06-24 | |
| A 5 |
Time Owned: 0 to 3 months. |
| This is my second MFJ-994BRT from MFJ. I had issues with the first one (probably the first one they made) but they did make good and I was sent another. That was when they first came out with it. Now, 4 years later, I did purchase another one. (The first is still in use at my Lake house.) This one performs flawlessly and matches my 80 meter loop on everything above 80 meters like it should. Highly recommend this tuner. Oh this version has a DC input on it so ... no bias-T needed. I have it mounted on a wall in my garage! de Frank KG9H |
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| KK8ZZ |
Rating:      |
2018-08-01 | |
| Fast, efficient, dependable! |
Time Owned: more than 12 months. |
Bought the DX Engineering mounting kit for this fine tuner, and gam using it with their famous 43 ft vertical with radial plate and 36 radials laid down on the grass with lawn staples. Radials disappeared under new grass in 2 weeks. Using the tuner ar the base of the antenna for low feedline loss per the DXEngineering installation suggestions. Was using 600 watt LDG inside the shack for 2 years before. WOW! Once you teach it a few frees on each band, it retunes in less than a second on your new frequency. Yes, I’ve used it on 160 successfully with the 150 feet of buried coax, again at DX Engineerink’s suggestions For easy matches on 75, 80, and 160m. Bought this one used at Orlando HamCation. Best ham fest purchase in years. I highly recommend this 600 watt weatherproof tuner! De KK8ZZ
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Earlier 0-star review posted by KK8ZZ on 2014-09-16
So sorry I had any faith in MFJ for this.... what a poorly-constructed (screws rattling around inside) hunk of crap... Martin, have your stuff assembled in China.. at least they can get it right.... |
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| N7UVH |
Rating:      |
2018-04-24 | |
| great tuner! Works as should |
Time Owned: more than 12 months. |
I picked up my tuner used. It gets used every day. Most the time at 100 watts. Durning contests, 500 watts. I have had problems with it not tuning. Was my shack fault. NOT TUNER! Found bad ground, bad coax connection which caused it to keep trying to tune. 40 meter would not tune. Changed twinlead feed line Boom fixed. Just as instructions said. I am saving to get the 1000w version. Cant wait to put on my 2nd tower. If you have one that is giving you problems. Most likely pilot error.
Murf
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