Manager - NA4M
Manager Notes

Reviews For: MFJ-971

Category: Antenna Tuners/Matching Networks

eMail Subscription

Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted.
Review Summary For : MFJ-971
Reviews: 55MSRP: 99.95
1.8 - 30 MHz 200 watt portable antenna tuner
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
PA3GMP Rating: 2002-05-06
Basic but nice Time Owned: 0 to 3 months.
There are two kinds to have fun with HAM radio. One is to buy the latest Wundermaschinen, plug it in, go on air and leave the technicalities to the hardware. The other is to use more basic equipment, do your own tuning and operating, and use skill rather than rely on sophisticated automatics. The 971 falls in the latter category.
This is a basic tuner: there's a switch to select the appropriate inductance tap (you pick the initial position for the strongest noise or by experience) and two capacitors that interact so that you need to retune several times. In short, you develop tuning skills as you go.

The tuner matches almost most pieces of wire and coax, and has a balun (that needs a separate jumper wire) so that you can connect balanced lines and antenna's.
The construction is about on par with most MFJ products: it looks cheap and a bit slipshod, but it will do the job, although it's just a bit on the sloppy side for products in this price range.
The cross-needle power/swr meter works fairly well but isn't entirely balanced in my tuner; it disagrees with other (calibrate) SWR meters as to where the exact 1:1 match point is; if the SWR meter indicates zero reflection, the actual match is 1.1:1. The deviation is small, though.

MFJ offers this tuner primarily as a QRP tuner. Having opened the case I agree with this: the tuning capacitors have a rather small plate spacing and the balun is based on a single, small toroid. On the other hand, the power switch has two settings: 30 and 300 Watts. In my opinion 300 Watts isn't exactly QRP, and I'm not all that sure that the tuning capacitors and the toroid balun can handle 300 Watts. My rig puts out 100 Watts, but I haven't tried anything above 10 Watts yet. When I feel braver than today I might try if the tuner can actually handle 100 Watts.

All things considered, it's a nice tuner. Not earthshaking, but nice.

KK9H Rating: 2002-02-03
Nice general purpose and QRP tuner Time Owned: more than 12 months.
I pretty much agree with VK2NEW's assessment of this MFJ tuner. I bought mine a few years ago when I was looking for a small travel tuner that could handle a typical 100 watt radio and had an SWR meter built into it. I ran across the 971 at a hamfest and it was just what I was looking for. When I got it home I looked inside and found that touching up a few solder joints and tightening of some the internal hardware was needed. I have owned other MFJ products in the past and found that fundamentally their product designs were fine but their manufacturing and quality control often was lacking. I also touched up the SWR meter's calibration and got it to agree quite close to my Bird wattmeter's readings. Lastly, I like to know when I am dialing up more or less capacitance so I set the tuning knobs so that on a scale of 1 to 6, 1 meant less capacitance and 6 meant more. I really like the small size of this tuner which makes it handy for vacation trips. Last year I built a Small Wonder Labs DSW40 QRP rig and the 971 tuner can be set through inernal jumpers for a very low 3 watt meter reading which is perfect for this rig. I have run the DSW40 with a 33 foot wire out the window and a ground lead running to a nearby center screw on a wall outlet. Tune up is a snap and signal reports are very good. I would comfortably recommend this tuner. It works very well, but it did need a little attention when new to get it in the condition I wanted. It should have been that way when it left the factory, hense the 4 rating.
VK2ATN Rating: 2001-08-24
QRP + MFJ-971 = PERFECT MATCH Time Owned: 0 to 3 months.
OK, I noticed that W3JJH gave the MFJ-971 a 4 for construction, well after opening the case of the tuner about 5 minutes after it was deliverd, I say that a 4 would be right on. You have to remember "you get what you pay for and it does not matter what it is".
Now for performance this is 1 hot little tuner, I could even get a 1:1 match on my aluminium window frame with a random length of wire for a counterpoise. I believe that when you operate QRP you should use a resonant antenna for the frequency you are using, which I do as at this moment I am only licensed for 80, 15 + 10 metres, so one of the main reasons why I purchased the MFJ-971 is for when I travel and I only need to carry 2 lengths of wire to make a end fed antenna.
I have noticed that a lot of QRP operators are using the LDG Z-11 automatic tuner, which is a excellent tuner but why pay almost twice the amount of money when you can buy the MFJ-971 which has a built in swr and power meters and to top it off a 4:1 internal balun for balanced feeders, and it may take you only 10 seconds to get a 1:1 match most of the time when the Z-11 will not.
So if you are in the market for a new tuner and you do not mind turning a couple of knobs to get a perfect match, have a look at a MFJ-971 and you will not be disappointed.
W5CGH Rating: 2001-06-22
Excellent tuner for the money Time Owned: more than 12 months.
I originally bought the MFJ971 based on the recomendation of a friend. I use it QRP both at home and in the field. It's small and light, and easy to pack for travel or backpacking. The dual needle watt/SWR meter makes tuning quick and easy. I regularly use the 971 to tune a random length end fed wire, and have virtually never had any problem finding a match.
W3JJH Rating: 2001-05-30
Good QRP Tuner Time Owned: 0 to 3 months.
I bought the MFJ-971 to use backpacking with my FT-817. I was all set to buy an automatic tuner and a QRP SWR meter when I noticed the MFJ-971. It works well and, unlike the commonly used QRP automatic tuner, has both an SWR meter and a built-in balun. I've been able to match any antenna I've encountered so far. Usually, I can tweak up a better match than an automatic tuner can. The 971 gives all this at less than half the cost of an automatic tuner.

As shipped, the SWR meter ranges are 30- and 300-W. Moving a couple on internal jumpers changes the ranges to 6- and 30-W.

I give the unit a 5 for performance but only a 4 overall. MFJ's products are good value for the money, but their construction practices are more like what one finds in third-world consumer goods than I would like.