It is a departure from the tuners that use a balun on the output. It is easy to use, once I log the settings for each band/frequency. That said, I think the 974H fills a definite niche in my shack. I use a venerable 275 watt Johnson Matchbox (modified) for the loop, to prevent excessive losses. The QST review showed a dismal 41% power loss on 80 meters with a 6.25 ohm impedance. I also have a delta loop, used for 80 & 40 meters, which has a very low impedance on 80 meters. The 974H is used for a 44 foot dipole (a Cebik favorite) for 30 through 10 meters. There I noticed the efficiency is good if the impedance is not too low. There is a review of balanced tuners in September, 2004 QST. It is is one of two tuners in regular use. Could have spent 3 times as much for a Palstar which I'm sure is better built but I balked at spending more for a tuner than my rig. Very easy to tune, the suggested settings chart are nowhere close to what I wound up using but you have to start somewhere.įrom my experience, would say the unit lives up to its specs just fine and is a good value for the money. Replaced match box with MFJ unit and happy to report it tunes fine on all three bands including 20 meters. Could not obtain a good match on 20 meters in particular, 75 was the only band that came close to 1:1 VSWR. Have an old Johnson 250 Watt Matchbox, it failed miserably to tune a 125 foot dipole fed with 100 feet of 450 ladder line. Inside of case was clean, solder joints looked ok, tightened allen screw and put the cover back on. Just received MFJ-974HB tuner, as most other reviewers have mentioned, had to tighten the coupling shaft inside the case to the inductor switch. Great value for the money, works exactly as specified.Įarlier 5-star review posted by W6IZK on Easy to obtain a match, repeatable dial settings, matches right down to 1:1 on the three bands mentioned. The MFJ Tech Dept was very frendly and helpful.Īfter nearly two weeks with the tuner, very happy with its performance on 75, 40 and 20 with the 125 foot dipole. If you want to play with end fed random wire (Marconi) antennas, this may not be a good choice. This tuner may have worked well with a balanced feed line (didn't try), but manual says it works with end fed wire and it didn't (even after try a variety of lengths). Returned it to dealer (and ordered a Palstar 1500BT instead). They agreed that it was 'defective' and gave me the option of returning to the dealer or to MFJ for a new one. The "antenna" tuning capacitor knob had little or no effect on the meter. Could not even get a near match on all bands 10-160m. Attached to the same lug, a grounding wire to the the house service grounding rod directly outside the shack window (tried both with and without this ground- ing condutor). Had plans for a 160m horizontal loop, but first hooked it up to a 120'(also a 144')end fed wire antenna with a 1/4 wave counterpoise on each band (two on 160m), the counterpoises were installed 14" above dirt and attached to the grounding lug. The metering is accurate and easy to read, the build quality is of a reasonable standard. (Yes it tunes my doublets on 6 metres and I have had some great contacts). I now have two of these tuners, the B model (80 -6) and the HB model (160 – 6). The same holds true when measured using various doublet antennas and overall I am impressed with this tuner’s performance. In making A/B measurements, using a pair of calibrated RF ammeters and various balanced loads, the MFJ unit comes very close to the the link coupled unit and, on some bands, is a little more efficient. The best, in terms of RF efficiency and balance, was always the link coupled unit but that is no longer the case. Z-match,T-match + 4:1 balun and a classic link coupled unit. Over the years I have acquired many different tuners i.e. I have always been a big fan of simple efficient antennas fed via open wire or ladderline.
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