MFJ 993B Tuner Review Amazing Automatic Tuning! 

Back in the brown shoe days it was called a Transmatch or antenna matching unit. Antenna Tuner is a misnomer, it does not "tune" the antenna, the antenna is still NOT resonant, so the power in the form of heat has to be dissipated somewhere, like in the coax that heats up and can burn if you use too much power. There are better matching solutions like the MFJ- 993BRT, 994BRT & 998BRT remote tuners (I have two in service and they work very well) that put ALL the power into the antenna and not the coax, plus it keeps the RF out of the shack. I will never use a "antenna tuner" in the shack again. George N2SQ

I just bought this tuner yesterday. It will be installed between my Kenwood TS 570 D transceiver and my Vibroplex Endfeed 135' antenna. Looking forward to putting some of your advice to work. DX had the tuner but not the interface cable (here in their Sparks, NV store). They are shipping the part from their headquarters and it arrives tomorrow. The manual is 44 pages long but I'm hoping to get this up and running with minimal trouble. Thanks for the helpful video. I have since dumped the Kenwood (gave it back to the friend who loaned it to me). I now have a Yaesu 710 AESS. The radio is magnificent (to my thinking anyway) and this tuner is working flawlessly. ------------------------- Two weeks later: I watched your video again and picked up some things that my 78-year-old memory and retention skills missed the first time around. I LOVE this tuner! It helps me get more contacts easier and the tuning helps me get good audio and signal reports. Thaaank you!

Excellent video, very professional yet down to earth presentation.

I have this tuner, i'm very pleased with it.

Nice review. I know many have made fun of MFJ over the years. I have several of their products, and have never had an issue. I've never encountered shotty craftsmanship either. Others I know have.

I have 2 of them and very happy with the way they work.

Nice video!

5 years late, still like it?

Thank you. I was wondering about mfj tuners. I gave my old one to my son. N0QFT

This video was very well done!

You might have taught me enough to purchase this tuner

You say that a swr of 2 is fine, just to point out that a swr of 2 is a load impedance of 25 Ohms connected to an expected 50 ohm , and when you impedances don't match you don't get an efficient energy transfer.

ARRL Handbook 2014 edition chapter 20.4.2 "...The antenna tuner’s function is to transform the impedance, whatever it is, at the transmitter end of the transmission line into the 50 Ohms required by the transmitter. Remember that the use of an antenna tuner at the transmitter does not tune the antenna, reduce SWR on the feed line or reduce feed line losses!..." This means that the system has been coupled to the transmitter and is balanced. However it does not mean that the radio will receive or transmit the signals better. The best way to accomplish that goal is to use good quality coax and connectors and tune the antenna for the frequency being used. A tuner can be of great benefit in certain situations but not more efficient.

From what I've heard on the coax... you might want to pull the case off and go through it before you just drive in that screw. Thanks for the video. Very informative.

Thank you for your information and I am thinking about getting this one...

Mine is about 13 year's old . Think it will tune a wet string on 160 hihi

To add a bit of info, just in case. This tuner is advertised as a 1.8-30 MHz tuner, but it works just fine on 6-meters too. What doesn't work (on 6) is the frequency counter.

Think I'm going remote antenna tuner for mine. Partly to declutter station, but also to reduce line losses.

Great review!

Good video. Having a tuner "cant hurt" and will protect your final amps in your transmitter. But I still maintain it doesn't help you radiate more RF. It just "fools" your radio into thinking it is tuned. (But I will get one to experiment with various antenna types and have piece of mind.) It should be noted that there are circumstances and antenna configurations and what you should never use a tuner. If you were using a magnetic loop antenna that incorporates a remote variable capacitor you should never use an antenna in addition.

Good advices...thank you

Hi Josh, it's Robert Lackey. Sorry for the lack of missing out on your live shows . Got that flu for way too long. All studied up. Gotta wait one more month for nearby license test. Important question? Because my $ is so tight for a while this is my last splurge for a long time. Hot a pro quad vhf/uhf, they stryker sr94hpc. Unlocked. So 25-30 mhz. Got the Hesenate HT-UV8R PLUS (3800mah) 8 watt. Other than my mobile antenna set, I'm going to build my own base antenna's. So I can sorta afford the MFJ 941e hf. 135$. Non- automatic. Seems more important than a vector analyser? Remember, I'm building my own base antenna 's . Lol more like alot of different types, best tool? I'll be listening tonight. Peace my friend.

There is something no body talks about.......which is that most tuners available today are high pass networks. There are low pass tuners that will work as a tuner but can also lower harmonics by 50 or more db. You might say, who needs a low pass tuner at this point in time?? One thing you might try is to measure the harmonic output of your transmitter or amp especially tube amps. You may find something you did not expect. I have been designing and building low pass tuners for years and my SS amps are much simpler since they don't need $500 harmonic filters. And reflected power is not dissipated in the output devices.

impact driver will get that screw in!

Do all tuners require that you place on CW,AM, or FM? Can you tune on SSB? Sorry for dumb question but Im new to the hobby.

Your background music at 9:09 sounds like the Webex hold music. 😄 Thanks for making me want yet more gear. 73 Josh, hope to QSO some time soon!

So, I just recently bought this antenna tuner and have the interface cable for Yaesu (FTDX-10). Even though my radio shows I'm transmitting 100w, the tuner shows only about 2-3 watts forward, no reflected power, and an SWR of 1.0. Any ideas of why the tuner would show such low forward wattage even though the radio says it's putting out 100?? Thanks.

Will the interface on this tuner work with a Kenwood TS-50S. If so....how would I find the cable ?

Any clue if the MFJ993b can tune without txing ? I know some ATU are able to get the frequency from the radio and change the data saved related to frequency. Thanks

I do have a comment regarding this particular A/T. Having used for a number of years the 941, I was able to fine tune it, in a way that the reflected needle, would not move. Now this one, even though I have selected via the menu, to have 1,0 SWR, in some cases, it simply can not do it by itself. Now the question is, can I fine tune using the C up/ down and /or L up/down, without reducing the power to 10 -20 W? As you know, with less power is less SWR. If I can not fine tune with full power of my transceiver (ic 7300), then, how shall I reduce even more the SWR manually?

Will this, or any tuner, help with reception?

I realize this was 2 years ago, but this tuner is at a nice price right now. Do you know if it will tune without input from a radio (sensing RF), I have a Xiegu G90 and an old Ameritron als 500m and am trying to get things running, even to the point of using a foot switch to key the old amp. kd9oam.

Can I use this tuner on cb radio with an max 2000 antenna?

I just bought one of these to go with my 200watt rig. I have the control cable in place and it tunes nicely using my rig's tune button. But at full power my tuner appears to be limiting output to 118w. I can increase the power up to this point and the indicated power onthe tuner matches the increase shown on the rig but will not pass 118. Switch tuner off and re-engage internal tuner and I get the full 200w output. Anyidea what's occurin ghere, is this in anyway normal? Tumer is tuning down to 1.0 - 1.5 swr

I like where you call YQ YQ @9:03 :-)

AT a price of around $350 you'd think that the screws would fit perfectly....hi.....

The interface cable for connecting the mfj to the 7300, is sold together with the mfj or seperetly? And how much does it cost?

Hi Hosh , bouvbt the MFJ 941e versa-tuner 2. Since I need to stay legal till my test, I hooked it up to the cb band. A stryker sr94hpc mat ched to a A-10 antenna. Love that radio and antenna. Soon as I hook it up as a base with the tuner all I can get is super hi swr All is grounded , even put some radicals for a ground plane. Completely in useable. Any ideas ?? Funny thing is in my .mobile I get 1.2 to one swr. I must be doing something stupid. Besides screwing around on cb bands. Though I talk all over go us on its stock ten watts mobile, no ssb.Thanks

will it tune a dual band antenna made for 2 and 70 meter to work for 10meters

Do you recommend mfj929 or mfj993b? 20$ apart only however mfj929 is significantly smaller for protability so what do u think

Yes new antenna ! I can just see the look on your wife just as you made that comment haaa . Ty 73👍🍺🤠

For new viewers FFWD to 7:50 :(

Prediction: in < 1 years time the features of the MFJ will be in all the new transceivers.

Have you tried the 993 on 6 meters ?

can a 993B be upgraded to a 993B ?

A far better tuner than the LDG tuners.The MFJ tune is much quicker than the LDG and will tune antennas that the LDG cannot tune on any given day.

wow come down to Earth lol

After the tuner reduces the SWR have you ever noticed when your speaking with SSB the display jumps all over the place causing the SWR to change?

2nd

its ok dude...

If your antenna is not resonant, its not going to transmit any electromagnetic energy so you may have a match, but you are still wasting your time.

1st!