| N6TEA |
Rating:      |
2011-09-09 | |
| It's Magic! Superior Compromise Antenna |
Time Owned: 0 to 3 months. |
Living in an apartment on the first floor is not conducive to good HF propagation but for this amazing antenna. When I asked the management if I could put up an antenna, they asked, "is there anything that looks like a satellite dish?" This is it! MFJ makes these to order. Mine took several weeks as I ordered it just after the Dayton Hamfest. I bought it from HRO who ships them free. Janet at Anaheim HRO kept me up to date on the ETA. Herself a longtime ham, she really knows the business of our hobby. Curious as to the quality, I propped the loop up on a soft chair in the living room and carefully removed the 26 screws that hold the ABS covers on. Inside I was amazed at the quality and pride of construction demonstrated by the aluminum welds on the HUGE variable capacitor and the solid, bright solder points (see my review on the MFJ website if you wish). One screw with its nut to help hold the SO-239 needed to be tightened slightly. I suppose it came a bit loose in transit from MS to CA via rumbling truck. Packaging was quite adequate. I used a Rig Expert AA-54 antenna analyzer to check the tuning of the end stub. No adjustments were needed for any band. All tuned 1.5 or better without the auxillary capacitor powered up. With power, I have learned to tune it between 1:1 on all but 15 meters which will come in at 1:2 - 1:4. To tune it, you first set the desired frequency (make sure your radio's internal tuner is OFF). Then add about 30W of unmodulated power (either CW or AM). Watch the needles. When they drop and the course tuning lights go out, either the up or the down light will be lit. Then, use the fine tuning as indicated up/down. I've learned to slow down as the needle falls using fine tuning. By doing this, you eliminate the needle "bounch" downward and get much lower SWR. Then, you may turn on your rig's built in antenna tuner to drop it dead on 1:1. You can even use the rig's tuner to extend the MFJ's bandwidth from the selecdted frequency. My antenna is mounted vertically on an MFJ-1919 tripod, a very rugged accessory. I use a DX Engineering 1:1 current choke at the shack entrance and have NO RFI in the shack nor is there any interference with neighbor's devices. By all means, read the directions carefully. If you have questions, MFJ tech support is more than happy to help. Just call them. The wait in not long. Clearly, MFJ succeeded in delivering a unique solution for stealth antennas. It is both well made and engineered. Now, the reality is you will probably not get 5/9 signal reports but from So Cal, I have QSO's from Magadan, East Russia (4,325 mi.), Molokai, HI (2,425 mi.) on 20 meters, and the entire West Coast, plus the Southwest, and FL so far on 40 meters. Signal reports on the more distant QSO's were low, but I got the QSO. I even got a 5/9 from a Sacramento mobile station (435 mi.). So, read the directions, install it carefully, use a 1:1 current choke, learn to tune it and you will enjoy ham radio from an apartment or anywhere.
73 de Mike Slate
N6TEA |
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| N0YXE |
Rating:      |
2011-08-30 | |
| UNBELIEVEABLE |
Time Owned: 0 to 3 months. |
The antenna was just installed and I just tried it out. The second attempt (after I realized what I was doing) to tune on Twenty Meters went without a hitch and occurred within a matter of seconds. It tuned to around 1:1 SWR. I called CQ and the return signal was 5 over 9 with the best audio I have ever heard! I thought AC8RD was next door to me, instead of 713 miles away!
After MANY antennas and attempts (and over two thousand dollars) I have found an antenna that will survive the Nazi Bastard Homes Associated that is guarded by octogenarians who spend other people's money (our dues) to patrol, threaten, and prosecute small unobservable antennas in resident yards.
If you would like for me to send you some great generic literature on magnetic loops and a picture of my stealth antenna, mounted at five feet on my deck railing, send me a note:
terryspaceship@yahoo.com
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| KJ6BBS |
Rating:   |
2011-08-11 | |
| Great working antenna/Horrible service and quality |
Time Owned: 0 to 3 months. |
Now I don't want to completely bash MFJ about this antenna, and this should be a review of the MFJ-1788, and not the 1786 (which I will discuss later), but the antenna works great once you get past the vague instructions, and can mount it without things falling apart.
1) Great reception; very low noise, and stations come booming in. I have the antenna only 7 ft. off the ground just outside my garage, and I get some fine results.
2) MFJ's customer service leaves a lot to be desired. I ordered the antenna in April 2011, didn't receive it until the end of July 2011. They charged me for it, without even notifying me that it was on back order since March 2011 (something they should have published on their site). Once I received it, in the excitement I wanted to get on 40 meters right away, so while tuning and tuning and tuning, it wouldn't tune, I soon discovered they sent me the 1786 model, and not the 1788, that I had ordered specifically for the purpose of getting on 40 meters, and here I am with the completely wrong model.
3) While mounting the antenna on the mast, the threads are press-in ones, that are pressed into the metal chassis, and all four had popped off while applying very little pressure on the wrench. This made the vertical mount practically unusable. So I had to take off the housing, buy new hardware (because the thread was not easily removal from the bolt), and wrestle with putting the mounting brackets back on with my own solution).
4) Lastly, getting on 20 meters last nite, I could tune easily on the high-end of the band, but when I decided to drop down to 14.070 MHz for some PSK31, the loop would not tune at all.
I would not be so irritated and dissatisfied if the antenna did not cost me a whopping $469.00, but for that much money, that thing should work 99.9% right out of the box, or with very little hassle. I would have given this antenna at least a 4, but the aggravation mixed with the high cost justifies the low rating.
As far as performing when it does tune, this antenna works great. The two QSO's I made so far on it, were into the Northwest (from my QTH), on 20 meters at 0400 UTC, with 58 signal. |
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| W6PDC |
Rating:     |
2010-07-09 | |
| Great Urban Choice... |
Time Owned: 0 to 3 months. |
Having been forced by the current economy/Silicon Valley employment scene to downsize from my half acre in the country (with yagis, verticals & wires), to a condo in the city (albeit on the second floor, and near to the rise of a decent hill), I was dismayed to toss out the usual 10-15' of hookup wire stuffed in the center of the SO-239s/BNCs on my FT-1000MP Field & K-2, and not be able to hear a peep on the HF bands, just a S-9+ QRN roar. A jaunt to HRO for a Timewave ANC-4 did allow me to discern a few signals on 40 & 20 meters, but couldn't even hear WWV on 10 MHz.
Thus, I "bit the bullet" and ordered a MFJ-1788 while at HRO, a bit dismayed (having prepaid) by the "no idea when it might ship," but pleased when it showed up on my doorstep less than 2 weeks later! Price is now about $40 more than mentioned here: $470.
Was pleased at the sturdiness of the shipping box (for those with $ concerns re. shipping- free with orders over $100 at HRO, and no doubt others)- must have been upgraded, since the decades old QST review.
Typical MFJ ("Mighty Fine Junque") out-of box experience, tho: missing the 4 1/4-20 bolts for mounting the antenna, and a suspcious "rattling" sound inside the thin plastic housing. The rattling turned out to be a "free-floating" 4-40 screw, which upon close examination didn't seem to have fallen out of any location, so its origin is a mystery. Two daisy-chained pairs of zip-ties loosely around the plastic housing- no idea of their purpose or origin (shipping box seemed sealed, so doubt a customer return).
Upside of having to immediately tear into the unit was seeing that the construction & parts were actually of reasonable quality, and thus, the retail price isn't out of line (tho also gave me the "chance" to tighten the quite loose 4-40 mounting hardware on one side of the motor-riveted on other side- for the cap: perhaps the source of "backlash" in other reviews?).
After a few minutes of getting familiar with the tuning/control head, was enjoying arm-chair copy of signals on both 20 & 40 meters (wife even popping hear head in, and asking if those voices were from the radio ;-), and early this morning, with the antenna simply propped up against the interior wall of the radio room, aka 3rd bedroom, was close to amazed to be copying (grayline?) several JA stations on 40 SSB S3-5! Looks like I'll be able to enjoy HF from San Francisco after all!
Given the sunspot cycle debacle (i.e., 10 meters not terribly viable for a few more years?), and my enjoyment of puttering with kits and restoring boatanchors on weekends, with the 40 meter West Coast swapnet on in background, & liking 10 MHz WWV access, chose the 1788 vs. the 1786.
Had it not been for the QC issues, would have given this one a 5 star rating!
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| JFROOT |
Rating:      |
2009-04-13 | |
| Very Impressed |
Time Owned: 0 to 3 months. |
I was wanting to get on HF but my living situation provided me very limited antenna and ground choices. After some suggestions from some Elmers I ordered an MFJ-1788. After waiting 6 weeks it finally arrived and I placed it on the flat metal roof of my apartment building using some PVC pipe as a mast into a patio umbrella stand. Ever since then I have been making DX contacts all over the place. My very first contact was with a Russian fellow on 30m using PSK31. I live in Vancouver, Canada so that was pretty impressive for me. Lately I have been getting into Europe, S.America and all over the US on 20m, 30m and 40m.
I can get the SWR down to 1.5 or lower every time on any band. The tuning system does take some getting used to, but after a while you will be able to re-tune to any band easily.
The build quality is quite well.. in a recent wind storm my whole antenna came crashing down onto the roof while i was away and filled up completely with rain water. When I got back I drained it out, let it dry and was back on the air.
I haven't used any other HF antenna so I can't say this is better or worse than anything else out there, but for me it works far better than I imagined.
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| AF2DX |
Rating:      |
2009-03-06 | |
| MFJ-1788 SWR BUGS? |
Time Owned: more than 12 months. |
Check the spring on the back of that big cap.
The cap has backlash and at times the cap will not stop where it should.
I inserted a buxxcom choke and now have zero RF on the feed line.
I also use CATV coax
Some times I may have a 1.3 to 1.5 SWR
I give the slow turn button a fast tap and I have the needle laying on the pin.
If you think your doing everything right then remove the coax and put a dummy load on in place of the loop.
The SWR needle should not move.
Hook the coax back on the loop and try reshaping the coupling loop
A mod I did on the MFJ loop was to feed the loop with coax from my rig to the loop and feed the DC 12 volt wires to drive the motor with a sperate set of wires.
This lets my RF go to the LOOP and not through the remote tuner
Read my post below and see where my loop is.
But my Pixie beacon was heard in GA and my Rock Mite beacon was heard in CUBA
BOB
AF2Q |
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| K4ELO |
Rating:    |
2009-02-06 | |
| Just OK |
Time Owned: 0 to 3 months. |
| I tried using the 1788 loop on the balcony of a 3rd floor apartment. Results weren't great. Either vertical or horizontal mounting. SWR can be tuned to <2:1 but it always seems to have a greater noise level and weaker reception than my screwdriver vertical under the same circumstances. Maybe I'm doing something wrong here. Also, the "Auto Band Select" doesn't work for me. Just keep tuning and watching the meter, then you can find the right point. I wouldn't buy it again, but maybe it's just my setup or location that's wrong. |
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| EA5BLP |
Rating:      |
2008-12-03 | |
| A great radiator |
Time Owned: more than 12 months. |
My 1788 is abt 3 m over the ground. No problem to tune it 1:1 from 21 to 40m. The performance is excelent on all bands, even on 40. I make DX on this band without problems almost everyday using 100 watts. Of course, the higher the band, the lower the power you need, but on 30 and 40 works also superb. Surprisingly fine for it´s size. The antenna is not only a good choice for restricted spaces, but a very good radiator for any situation. No complicated instalations on the roof and a very good compact antenna. This is not a compromise radiator, but a real high performance sistem. Tunning it whenever you cahnge the frecuency is not a problem when you get used, it´s only a question of a few seconds. Even working QRP, the antenna shows a great behaviour. Otherways, it´s sensible to rain and wind. You must take it in account if SWR raises one day and suddenly is normal again. A minor problem compared with all avantages of this great antenna. I have had yagis, rotary dipoles, verticals, loops...After my experience with antennas i would say this one is perhaps the most interesting I have never tested.
73. |
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| KA4AIY |
Rating:     |
2008-10-05 | |
| Still works for me |
Time Owned: 6 to 12 months. |
Previous review still applies; wish to add that the addition of a Buxcomm UNUN RF Isolator seems a near-must as it makes the tuning easier/more accurate versus without it. Originally, I followed the usual "gospel" of forming an isolation loop in the feed line coax. I removed the coax loop and installed the Buxcomm UNUN and viola! Easier to tune to find that coveted Hi-Q tuning niche. I am getting good RST reports while running only 20 watts out; I tune all bands to a 1:5 SWR or slightly less without an Antenna tuner (I find that an auto tuner complicates finding that Q spot quickly)
As I reported earlier my less than perfect rating is based on construction of the unit.. I contend it is not well-built vis-a-vis it's high price tag when you high shipping costs due to box size and weight. |
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| M0NKD |
Rating:      |
2005-06-24 | |
| Simply Fabulous |
Time Owned: more than 12 months. |
| I've had spectacular success with the MFJ-1788 Loop. I commonly use mine on 40m and have it mounted vertically, less than 5' off the ground. Many stations have commented how good my signal is and have been stunned when I've informed them what I am using. The controller also has a built-in battery case, so the aerial can be used for portable work as well. I guess the controller could be improved to make it fully automatic, but that is really just a very small niggle. A really excellent antenna, costly, but worth it! |
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