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Reviews For: MFJ-989C

Category: Antenna Tuners/Matching Networks

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Review Summary For : MFJ-989C
Reviews: 144MSRP: 360
Description:
Handles 1500 watts PEP SSB output power
Product is in production
More Info: http://www.mfjenterprises.com/products.php?prodid=MFJ-989C
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
001442.7
KC9GI Rating: 2003-03-22
Works for me ! Time Owned: 0 to 3 months.
Well it seems like everybody has had bad experiences with this tuner, I just bought a used one and it works GREAT! I am not trying to load up a garbage can or the neighbors wire fence with it thou. My antenna is a Carolina Windom, 40-10 meters, fed with coax. I noticed some of the same problems as many people have experienced, wattmeter inaccurate by reading 10 watts low (so what), tuner doesn't sit flat on desk (I reversed the wire bail 180 degress & it sits perfectly flat now), roller counter not centered in window (it is adjustable on the backside of the panel by 2 screws in a slot), I disabled the internal dummy load and added a so-239 panel mount connector to the rear as I use my Heathkit cantenna for a dummy load (yes I run a KW thru the tuner, Heathkit SB-220). I believe my tuner may be an older version as the previous owner (now a sk) wrote on the manual a date of 1992. Also mine has the rounded corners on the cabinet and a belt drive for the roller counter. I have owned several MFJ tuners over the years, and they have always satisfied my requirements, usually sold them to upgrade to a higher power capable model or just to try a different model. I operate SSB with a KW input, SSTV with a barefoot rig. Would I buy another MFJ tuner if needed--YES.
WD2AEV Rating: 2003-03-19
Junk Time Owned: more than 12 months.
I used this tuner with an IC-706 @ 100w. Bought brand new at HRO. Out of the box the roller was out of round(cheap pvc supports) and the turns counter skipped and the band switch knob was loose. Matched 200' doublet ok fed with open wire. But was still very finiky on 160. Tried it once with 1000w during a contest at friend's house with an inverted L on 75M. Smoked and melted the the roller. Still have not decided whether i will repace the roller. Overall impression very cheaply manafactured. I will NEVER buy another MFJ product.

MFJ = Mother F**k**g Junk
KD3JF Rating: 2003-03-04
I have used mine for 6 years and love it. Time Owned: more than 12 months.
I have had my 989C for 7 years and have found nothing wrong with it. It does the job. I have loaded it up with 1000 watts PEP and no arcing or any other problem
Paul Gates, KD3JF
W4ACW Rating: 2003-03-04
GARBAGE Time Owned: more than 12 months.
counter skips,wont handle legal limit,smoked more than once and now no longer works.Wont waste time on fixing it.Resonant antennas for me now.
HL5FRF Rating: 2003-02-20
VERY POOR Time Owned: 0 to 3 months.
I DO NOT RECOMMEND IT REALLY!
CHEAP MATERIAL AND BAD MECHANISM MAKE ME ANGRY.
KC4VFP Rating: 2003-01-14
Good Idea, BAD INDUCTOR Time Owned: more than 12 months.
I picked this up at a Hamfest, and took this home with a bunch of other goodies. I bought this because of the roller inductor, which offers broader range than a fixed, tapped inductor.

I was shocked, to say the least, when I opened the cover, and found that the roller inductor had heated up sometime during its life, and caused each of the four PVC coil supports for the roller inductor coil to bow out! This is NOT a coil that is wound on the outside of a circular ceramic core, but a CHEAP attempt to make a variable inductor whose tap rides on the INSIDE of the windings, and whose coil is held taught by four rectangular pieces of PVC, spaced 90 degrees apart, with notches to hold each winding of the coil in place.

Do these "engineers" really think that dumping a kw into an accidentally mistuned (that's why they call it "amateur" radio) antenna tuner will not produce HEAT. Now I know why someone mentioned smoke billowing out. PVC burns. Someone should have told that to the people who tried to save a few bucks on the design.

Another thing that I found was that the PVC became hot like butter, and ran between the windings, lifting the roller portion away from contacting the coil as it passed over the PVC supports, presenting a further FIRE HAZZARD. I took a knife, and scraped away the plastic that was lodged between the coils. Now the roller made contact with the coil 100% of the time.

Now for the bowing problem. This was causing the coil to physically move as the roller applied pressure to the coil. I took a couple of pieces of strong cable ties, and put them around the outside of the PVC inductor supports, being careful to run it UNDER the mechanically switchable tap, and pulled them taught. Problem solved.

Had the inductor been properly made, this tuner would get a much higher mark. I work with broadcast equipment, and have never seen a PVC coil form for a tank circuit!

Don't let the class of license fool you, I held an FCC 1st.
WA5SSB Rating: 2002-12-31
Okay for the price. Time Owned: more than 12 months.
Variable coil control feels flimsy. Some grounding thing fell off the variable inductance control shaft, but it still works without it.
WA6BOB Rating: 2002-12-21
A good tuner Time Owned: more than 12 months.
I have used this for the past 10 years with a Collins 30S-1 amplifier in the RTTY mode with a full KW.

Once the settings are obtained and logged for each band and antenna, with an analyzer, they are accurate when preset the next time.

The only complaint is replacement of the belt drive from the inductor to the turns counter every three years
KB0WNW Rating: 2002-11-15
No problems so far. Time Owned: 6 to 12 months.
I'm glad to report that I haven't had as many problems as the others.

When I took it out of the box and set it on the bench, I noticed that one corner wouldn't touch so it wobbled back and forth......just like so many others listed here. I slipped a small piece of folded paper underneath and it took care of the problem. Other than that, I've run 600 watts thru it without problems.

The other day I decided to disconnect the internal 90 watt dummy load, install a female plug (I think it was a SO 239) on the back of the unit, and reconnect the wire from the multi-position switch to the new female plug. I noticed a capacitor was attached to the internal dummy load and then to ground. I called MFJ and spoke to their tech support people. They were able to tell me very quickly that the capacitor wasn't necessary. My finished modification allowed me to run a short length of coax to a full power oil filled dummy load and eliminate a redundant in line coaxial switch. Why MFJ decided to include such a small internal dummy load on a full power tuner is beyond me. I think my modification makes more sense from a design perspective.

While finishing the above mentioned project, I noticed that everything was tight and very clean on the inside. Nothing was out of place or bent. Once I put everything back together, the case wobble disappeared. Apparently all it needed was a little stress to be relieved in the case.

The main dial with the counter doesn't move as fluidly as I would've hoped but it isn't that bad. I'll check the gear alignment with the counter as someone else mentioned here.

The only thing that really bothers me about this tuner is the quality of the cross needle meter. It really is a piece of junk. It is so terribly inaccurate and unresponsive that you can't even use it. As far as I can tell, this meter is strictly for looks.

I'm glad to have bought a unit without the problems that so many reported. Good luck and 73's

Todd
KB0WNW
KO4NR Rating: 2002-06-19
Works OK!! Time Owned: more than 12 months.
Mine works ok and I have put 1KW in it on many occasions. I regularly run 600 watts PEP or so in it with no problems. I do open it up periodically to tighten screws and clean connections. A little Preventative Maintenance goes a long way!! Personally I think it should have better components and craftmanship for the money I spent for it but it does work for me!!

I have used it sucessfully with a G5RV, Ground Plane vertical and the NB6Z antenna explained in the eham article section. So far so good, Good Matches!!

73,
Bill