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Reviews For: MFJ-1786 Super Hi-Q Loop

Category: Antennas: HF: Verticals; Wire; Loop

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Review Summary For : MFJ-1786 Super Hi-Q Loop
Reviews: 68MSRP: 379.95
Description:
High Efficiency 10-30 MHz Continuous Coverage Magnetic Loop
Product is in production
More Info: http://www.mfjenterprises.com/Product.php?productid=MFJ-1786
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00684.3
DL3MGG Rating: 2013-05-13
Now 8 years of good working Time Owned: N.A.
My loop is now 8 years old and it is still working like on the first day. The antenne is mounted at the rooftop with a rotary. I am also using an automatic matched longwire with 18 meter but in most of the contacts my partners could find no significant difference to my loop. Especially in the evening and
nighttime the loop can make a better job, because of lower noise from the nightbours TVs. Special modifications I did: I removed the matching Motor of mfj to a buehler motor with gear and about 2 turns p. min. Found it at ebay. The modification is very easy to do. The other mod: I closed the housing with a silicon glue, so it is better protected to rain, snow, weather. All in all Im very satisfied with this antenna, would not like to miss it.
WX4DM Rating: 2013-04-06
Works great in my attic Time Owned: 0 to 3 months.
I recently bought this antenna and hung in horizontally in my attic. This causes tx/rx to be omni-directional and helps prevent RFI to/from the house. Reception is fantastic - I regularly hear central Europe from North Alabama and have even heard Perth Australia. I've also been able to speak with multiple stations in Europe and reports are mostly 59. I ordered directly from MFJ and they were wonderful to deal with. I'd definitely recommend this antenna.
K8RBW Rating: 2012-07-05
Most Impressive Time Owned: 0 to 3 months.
There is a real tendency to complain about MFJ and their apparent lack of quality control. Indeed, I have found myself to be no exception to this proclivity. In most cases, however, I have found most of the things they manufacture to be adequate and the quality control acceptable. When they fall short, I have found them more than willing to honor their "no matter what guarantee" with no bickering over details. In some cases, their products are truly exceptional. The MFJ-1786 clearly falls into the latter catgegory. I have always struggled at my Wisconsin condo to put up adequate antennas that don't offend the tender psyche of the "architectural committee" for the condo association. My neighbors have graciously allowed me to toss end fed antennas over on the decks, but I have always felt like I was imposing. I have managed a stealth screwdriver antenna with capacity hat that I conceal in my patio table that performs adequately on 20 through 40 meters. Everything above 20 has been problematic, however. With improving propagation, I wanted something that worked well on the higher frequencies. After reading the reviews of the 1786, I took the plunge. I am very happy that I did as it has performed well beyond what I had expected. Mounted on a portable TV tripod on my deck at 30 feet, it is a stellar performer. Indeed, I have found that it probably works as well as a dipole at the same height. For one who spent many years tuning up boat anchors, I find the need to retune when changing frequencies to be be no real burden. Like the olden days, it just comes naturally and you give it little thought. When not in use, I simply bring it indoors and nobody seems in the least concerned. Well done MFJ! You deserve a pat on the back for a very nice product.

Vy 73 to all, de Dick K8RBW
K1CM Rating: 2012-06-17
MFJ-1786 - excellent Time Owned: 6 to 12 months.
I bought an MFJ-1786 (30M to 10M) Super Hi-Q Loop Antenna about a year ago and hung it vertically in my attic, which put the bottom of the loop at about 28 feet above ground. The loop is suspended from the ridgepole with twine. It has worked much better than I expected it would.
I had thought that loops were kind of gimmicky, but this one changed my mind. After tuning the antenna several times, I was able to get very close to minimum SWR just by listening to and peaking the noise on the frequency (hint: turn off the noise blanker while tuning). The Hi-Q of the loops means that you will have to tweak the tuning when you move more than a few kHz.
I operate mostly QRP c.w., and I have found the 1786 to be every bit as productive as dipoles (30M & 20M) at about the same height, and the loop is much quieter. Loops do, however, have narrow, deep nulls along their axes. I had thought about rigging up a rotating system using strings from the shack, on the floor below the attic, to move the null around. But I decided to get another loop (an MFJ-1788, which covers 40M to 15M) and mount it at a 90 degree angle to the first loop. They are about 15 feet apart. Depending on the direction of the incoming signal, switching between loops (on 30M to 15M) can make the difference between just barely hearing a weak signal and being able to copy it.
As to the quality of the units, I can only say that they have worked flawlessly. I have not taken the covers off the control boxes or the loops, but the units look well-built from what I can see. Both of the loops came with control boxes marked “MFJ-1786.” They must have run out of 1788 boxes.
They both exhibit one minor quirk that I haven’t figured out yet: If they are shut off and turned on again sometime later, they will have drifted slightly, but it takes just a couple of taps on the Fine Tune buttons to retune them.
Read the manual thoroughly, and understand it completely, before using the loops. I recommend these loops to anyone who cannot install full-sized outdoor antennas at their optimum heights.
N0YXE Rating: 2012-05-25
BABY BROTHER Time Owned: 0 to 3 months.
I have just purchased the MFJ 1780 mini box loop for inclusion in my attic, next to the Alpha Delta DX-EE inverted dipole. The 1786 was fun and worked well. But, I received a court summons from my homes associatiion to remove all stealth antennas. My attic is protected by my middle aged buddies, Mr. Sig and Mr. Glock. Both being 45. You would not believe the ransom note that the hoa and their asshole attorney held me up for. If you would like to see a copy of the summons and the ransom note, I will send them to you. Also, I will send a good picture of the loop and the mini controls as it appears in my shack. An on the air review will follow soon: WRITE TO ME AT:
terryspaceship@yahoo.com
N6MV Rating: 2012-02-20
Only 3 ft in Diameter and 3 ft Off the Ground ! Time Owned: 0 to 3 months.
Relocated to a development with CC&R's, so left behind the 55 ft Tower and 3 El. Yagi- that I used for 32 years and went about looking at everything possible to use for an HF Antenna, viz. loading the rain gutters, using a stealthy flagpole, as well as using a small Hi Q Loop.

My MFJ 1786 Loop has been in use for only 2 days now, located only 3 ft off the ground,and I was very pleasantly surprised at how well this loop works on 20, 15 and 10 meters, for I was able to hear and speak with others on the East Coast, in Europe, Japan and South America - with ease, running 150 watts. Tuning is not that difficult once you get the hang of it, using the Auto Tune and Fine tune buttons, while looking at forward and reflected power.

Recommend buying an MFJ 1786, and once you see how MFJ built the loop and the controller ,you can then go forward with building one for 40 and 80 meters, using copper tubing for lower resistive losses, along with a vacuum variable capacitor so you can run more than 150 watts.

Best Article on the web - with many photos and references - including an Excel Spread Sheet to design your own Hi Q Loop is located at:

http://www.aa5tb.com/loop.html

No question about it, the MFJ 1786 Hi Q Loop is an excellent antenna for those who have restrictive CC&R's and I have no regrets in purchasing it- whatsoever - for it works great !

And, if you would like to see what an Exposed MFJ 1788 Loop looks like- one can be seen at:

http://www.g1zrn.net/1788.htm

Upstream,the challenge is to build a servo- stepping controller that automatically tunes the loop as one changes frequency - for this is the only negative of using a Hi Q Loop.

73's
K2NCC Rating: 2011-09-07
more bands for the buck Time Owned: 0 to 3 months.
It may take a month or two to receive this antenna. I used the extra waiting time reading the 1786 manual. There are used MFJ loops cheaper, but I recommend you pay the extra 100 bucks and get support with it.

Inspect inside the box before walking out the door or accepting delivery. "Figure 8” shaped antennas have been reported due to mishandling.

It's delivered in a big box, so it won't fit in a compact sedan if you're going down to HRO to get it. It fit in my Nissan Sentra after I removed it from the packing. But consider the possible need to return/ship the antenna before discarding the box. Don’t bang it up going down the road.

If you’re after DX, over 20 feet up and horizontal is the way you’ll want to install it.

Check all the bands you can work before nailing it down. One band might be fine while another is useless. I’ve had zero problems on any band so far.

Installs in less than an hour if you’re prepared.

Don’t forget to disconnect EVERYTHING between the control box and the antenna. Well, except the coax of course! No low-pass filter, no lightening suppression, no balun... nada.

I did pound in a dedicated isolated ground to strap to the braid of where the coax enters the house. I use real LMR400, which I recommend. Low-loss line is best with this antenna. You’ll also need a short run of coax to bridge the radio to the 1786 control head. Keep it short.

BE SURE to watch your SWR meter or the control box as you TX, since small adjustment are sometimes necessary. If your tuned antenna suddenly shoots up in SWR, tap the slow tune up or down once or twice and you're back in tolerance.

Tuning is really narrow. Nearly any frequency change will require a re-tune of the antenna. The mag-loop can be tuned by ear with eyes on the meter, otherwise, use a solid, stable tone when tuning the control box. Whistling won’t do it, so use a key or your radio’s tune tone.

Not that it’s a high noise level at the QTH, but I found the loop just as noisy as my previous antenna; a 20M homebrew half-wave dipole. Both measure a noise level around 3-5db on 20M mid-day. However, considering where I had the dipole compared to the loop, I wouldn't be surprised if I received some gain from loop.

SWR was below 1.5:1 on all six (really *7*) bands. Everything does as expected. Easy to tune, although frequently required.

I seldom give a day-one review, but my first impression is a solid 5. Not enough bad things to lose a star. Although I’m not confident this is a 10 or 20-year antenna. Another reason to buy new.

There’s enough good that I’d recommend the upgrade to anyone with a compromised antenna or restrictive QTH.
ON5UN Rating: 2011-09-06
Amazing antenna for restricted space Time Owned: 0 to 3 months.
I ordered the MFJ-1786 from Classic International in Roermond ( Netherlands) Got it well packed 3 days later. I packed it out immediately and found that the mains adapter for the remote control box was a USA version 110VAC, a simple mail to Classic International solved this and I got a European 240VAC one 2 days later. The finishing of the antenna is not the best and I expected that from MFJ, but a little filing solved the not perfect alignment of the mounting clamps holes. I have tested the loop at a height of 1.5 meters above ground on 29 August and compared it with my ground mounted Hutsler 6BTV with 30 radials .( Hutsler 6BTV has no WARC bands)

In general the Hutsler 6BTV has a noticeable better result, however the loop gave an unexpected result. I made that day 29 QSO with the mag loop in JT65 mode and this resulted in 15 QSO with USA, 3 with JA, 5R8UO and ZP9EH, the other QSO were all inside Europe. Pretty amazing! All with 30 Watt.
Tuning with the control box is easy ( and very sharp) Very good SWR on all bands, except 18 MHz where I cannot get it better than 1.8

Advantage is that the antenna can work on 18 and 24 MHz. If you have only a small space, a magnetic loop is the antenna to consider, but do not expect it will perform like a beam or a larger well placed antenna. And Classic International service was also perfect.
KJ4EBE Rating: 2011-07-01
Great antenna, but... Time Owned: 0 to 3 months.
Well... this is a great antenna. Easy to tune, great when receiving and very good when transmitting. It is incredible how such small antenna can perform that well. This is not just a highly compromise antenna for small or restricted places, this antenna really give you a very acceptable performance even at only 10 feet over the ground. Obviously it is not a bean at 100 feet but this Loop can compare to any multiband vertical.

Now the "but" part... the mounting clamps holes... well, not a perfect matching with the antenna mounting holes. So I had to buy a Dremel and work out the mounting clamps holes until they fitted with the antenna holes. Not a big deal but I had to spend $40 on a Dremel.

Like antenna the MFJ-1786 is a 5, but the quality control needs improvement. I gave a rating of 5 because, after all, the antenna is performing great.

I recommend this antenna if you want a great performance on a small package.

If you have any particular question email me and I will be happy helping you. My email on QRZ.com
CT1DRB Rating: 2011-06-05
Perfect antenna for my situation. Time Owned: 3 to 6 months.
Hello all,

since some time I have this antenna, knowing that till end of my life, since I still live in this building (it is very difficult to buy a new home up to now in Portugal), I will not have any kind of antenna on building for sure for ever.

This antenna is my gate to HF and up to now is working fine, of course I use it inside my home, signals are not that strong, but I am able to work some interesting DX's like VP5/W5CW or PZ5RA.

Best 73 to all.