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Reviews For: MFJ-934 Antenna Tuner/Artificial Ground

Category: Antenna Tuners/Matching Networks

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Review Summary For : MFJ-934 Antenna Tuner/Artificial Ground
Reviews: 9MSRP: 179.95
Description:
1.8 - 30 MHz 300 watt artificial ground / antenna tuner
Product is in production
More Info: http://www.mfjenterprises.com/products.php?prodid=MFJ-934
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0094.4
K3MOV Rating: 2018-04-10
Even works on 160. Time Owned: 6 to 12 months.
Please see my review of 12/5/17. I have been meaning to add this for several months. Thought I would take a shot at 160 with my 63 ft wire during the 160 contest. Got swr down to close to 2:1. Lowered power. Made over 20 contacts in about an hour. I don't understand why more antenna challenged folks don't give this box a chance. Write to me if interested. 73,K3MOV
KF4ULD Rating: 2018-01-17
VERY UNDERRATED! Time Owned: 0 to 3 months.
I have an LDG 100 ProII and an MFJ 993B and this will tune my G5RV Mini to 6M almost perfectly and the LDG and MFJ won't come close to it. It's slow and manual but the feeling I get having such a very low SWR compared to the other two is worth it. Plus, it's perfect for the campsite where power is limited as this needs no power supply except for the meter illumination. 73 / KF4ULD
WB3D Rating: 2014-09-28
Tuner and Ground Matching Work Time Owned: 0 to 3 months.
I live in a condo and use a 30' 22 Gage wire antenna deployed out the window into a palm tree with a variable length counterpoise in the shack. The 934 tunes 10-40 meters appropriately (as does the MFJ 971 and 901). I have had issues with RFI in the shack especially the computer. I do a lot of digital modes. The Ground Matching section of the 934 does a good job in eliminating the RFI. However, it was necessary to adjust a cover screw that was shorting out the Ground Matching inductor prior to getting the inductance working. This is a new unit right out of the box manufactured this year. Now works great! Wish I had gotten it sooner. The 5 is for performance.
TA3EP Rating: 2013-01-24
Great tuner Time Owned: 0 to 3 months.
Great tuner. Artificial ground is really functionel. It tunes my FT 857D smoothly at full 100W. output. Antenna is a 30 ft. longwire outside the window and 30 ft. counterpoise on the carpet. Works great on all HF bands and even on 6 m. No bad surprises, no electrical arks or any other botherings. I would recommend it.
WB3FXW Rating: 2012-01-15
It works, now Time Owned: more than 12 months.
I have owned the MFJ-934 unit for 18 months. When received it did not function properly. I took the top cover off and again tried the tuner. It worked. That was a major clue about what was wrong. The two inductors were not level. They should be evenly spaced between the case bottom and case top, A straightedge across the top, front to back, confirmed that the inductors would short out against the case. I carefully bent the brackets that held the inductors to the case bottom until 3/8" space was above and under both inductors. Now the MFJ-934 works flawlessly. Had I not had a DOA unit on arrival, the rating would be a 5.
Buzz, WB3FXW
K7GLE Rating: 2007-10-10
Functional but not great Time Owned: 6 to 12 months.
I have owned this unit (which looks different from the illustration on this page) for about a year. New Technician + HF license, old TS-530 driving a 25’ single wire antenna against a relatively close-by cold water pipe ground.

Out of the box it tuned the antenna acceptably across the HF bands I was licensed for but the ‘artificial ground’ function behaved strangely…the ‘reflected power’ needle (on the cross-needle power/SWR meter) would simply freeze and the ‘power’ needle (which is supposed to register your ground tuning adjustments) would not register at all, regardless of adjustments.

I returned it to MFJ, who promised me quick turnaround because it was such a new order. Ha. I didn’t get it back for nearly a month, even after repeated telephonic assurances it was ‘shipping out today or tomorrow.’

The ground adjustment did function after repair. I never experienced any RF in the shack (that I recognized, anyway…new ham, remember, and I was only using CW, not brushing my lip against a mic). I have upgraded my license and am using *somewhat* improved antennas (a simple vertical pipe with 2 radials trimmed to 40M, and a 10M vertical dipole whose top el is about 25’) now. I have no trouble tuning up to 1.5:1 or better on any HF band with the 934 – at what cost in signal loss I can’t say.

I get no response at all anymore from the artificial ground adjustment…nothing. Could be my excellent antenna systems?

As mentioned by others, I have noted some hand capacitance, but it’s only troublesome on 10M, where the tuning is particularly ‘twitchy.’

Overall construction seems lightweight for a supposed 300W tuner. This last weekend I noticed some internal arcing for the first time at 100W on 40M but haven’t looked into it any further.

Glenn K7GLE
KE5AKG Rating: 2004-04-04
my favorite piece of gear Time Owned: 0 to 3 months.
I bought this tuner after I could not tune my attic dipole on several bands with the autotuner built into my transceiver. It tunes the dipole well, but I had even better results with a 70 ft
random wire and several counterpoise wires running around the room and out of the window.
With this setup I was able to contact 12 DX countries on 3 continents within 2 days (there was a contest on) using only 100 watts. After this positive experience, I installed a 50 ft
random wire antenna on the top of my rv in a v-shape. It is attached to the ladder and roof rack with dog bone insulators and nylon rope,
and to a 15 in long PVC pipe standoff in front
With this setup I so far made contacts as far away as Maine and Aruba on 40m and 20m. I did not get the RV setup to tune on 10m, 12m or 160m, but I hardly ever use those bands anyway.
Overall this is an outstanding piece of equipment for wire antenna fans like me. It is a great value for the money. My only gripe (minor) is that it has "hand capacitance", meaning the SWR changes when I touch the tuning knob, which can make it a little tricky to tune on some bands. Also, I wished they would make a higher end version of it with higher power handling, so that I could use an amplifier for my base station.
N0EYE Rating: 2003-03-20
Peforms well Time Owned: 0 to 3 months.
I bought this unit because my shack is on the 2nd floor of our house...too far away from earth ground. The tuner performs well. I am able to tune my 130' dipole on all bands, 10-160M at 100W with no arcing or other problems. I believe the shafts of the tuning capacitors need to be better isolated, as my touch will affect the SWR readings.

The "artificial ground" seems to be functional, as I have no RF problems in the shack.

As the previous review said, the documentation could be a little better. I find it a bit confusing in places, but I've seen worse manuals too.

I would recommend this unit.
KB4COM Rating: 2002-04-05
Nice Unit Time Owned: 0 to 3 months.
I live in an apartment, on the second floor. Due to being a renter, I can not run a proper RF ground. This being the case, I had significant problems getting reasonable SWR's on my antennas (I am using mobile whip types, in a mag mount, on the balcony). The MFJ-934 has shown it self to be capable of reducing the SWR's, to a great extent. Unfortunately, there are other problems here, that I can not control (like aluminum siding).

I have been able to use the "artificial ground" feature, but I would like to see improvements in the manual, it is somewhat short, and the illustrations are a bit confusing. Overall, I like the unit and feel that my money was well spent