| LZ2CSK |
Rating:      |
2022-12-26 | |
| A great compromise antenna |
Time Owned: 0 to 3 months. |
| I bought this antenna as a compromise due to living in sts Constantina and Elenor varna Bulgaria, Apartments galore. I* read the instructions and followed them to the letter. MY BALCONY SPACE IS LIMITED but i got it installed and had a SWR of 5. i used my mfj 207 antenna tuner not automatically but direct hook up for manual use. and got a SWR of 1.2. In the first day i got a weak reply from l2mm? in Argentina but was drowned out by high-powered italians. not detered i persevered and using my rigs 175 watt pep made contacts with Australia, Sweden, Vatican city Stuttgart, and numerous Italian stations. all with 5.9 reports. so people contrary to what some people say this is a superb antenna. definately worth a 5 rating |
|
| G4HUN |
Rating:      |
2020-11-01 | |
| Agreed - Fiddly, but works! |
Time Owned: 0 to 3 months. |
I purchased this antenna in order to do FT8 form my first floor apartment in the centre of Norwich.
Once you've created the choke, etc, the antenna is easy to set up and take down.
I agree with others, that getting the SWR somewhere within the range that the ATU on my IC-7300 can handle it is a bit fiddly; but I purchased a MiniVNA for £40 that makes the job much easier. And of course you're only using a spot frequency on each band for FT8, so no need to keep retuning the antenna.
Results so far are much better than I expected; and PSK Reporter shows just how well the antenna is doing - with reports from VK and Antarctica. Plenty of QSOs in the log on FT8.
Money well spent, in my book! But manage your expectations overall. |
|
| WB7DND |
Rating:     |
2020-05-06 | |
| Fiddly, but works. |
Time Owned: 0 to 3 months. |
6 week update
Have used this antenna for over a month now. Rating has not changed but I have a little more experience to support it. Overall, it is a good compromise for bad circumstances.
These antennas remind me of the old saying about bumblebees. Theoretically, their bodies are too big and their wings are too small so they can’t fly. Nevertheless, they do fly. These antennas are too small and too inefficient to work. Nevertheless, they work. The concept is not new. William Orr has a similar antenna - antenna in a wooden pole lamp housing, loading coil in the middle - in his 1972 book Wire Antennas and, more recently, W5ALT reports great success with a bottom loaded indoor vertical made of materials costing about $5. (Just google “W5ALT” for a link to his article.)
The Orr and W5ALT antennas are designed to work indoors where a wood frame and siding would not greatly inhibit signal transmission. They would not work very well in a Faraday cage environment, such as a steel framed apartment building. That is my situation. This MFJ antenna is designed to be mounted outside the cage - sticking out a window or on a balcony. My balcony is 10 floor up. I mount the antenna on a tripod so I can bring the antenna indoors, out of the weather, when not in use. (The antenna should not be left outdoors in bad weather.) I use a metal strip with a 90 degree bend in the middle, 4”x 4”x 1.5”. I mount this on the tripod with a C clamp and then attach the MFJ bracket to the metal strip with C clamps.
On 20 meters, I have a small magnetic loop that, at 25 watts input, performs as well as or better than this antenna at 75 watts and is easier to set up. So, I prefer that antenna on 20. However, this antenna performs adequately on 20 and gives a 235 KHz range of swr at 1.6:1 or less. On 30 meters, the entire band is easily covered in swr of 1.5:1 or less.
This antenna really outshines the loop on 40 meters, however. From Oregon, I get 559 to 589 reports from stations 500 to 750 miles away. I have worked Arizona, Texas, Midwest and east coast stations in QSO parties with this antenna on 20 and 40. I am not breaking any pileups and I am asked for a lot of repeats. However, in hour long evening 40 meter events, I get 1.5 to 2.0 times as many QSOs with this antenna as with the loop.
Over the 6 weeks or so that I have had this antenna, RBN reports for 40, 30, and 20 are usually in the teens when conditions are decent, single digits when not. Except for Alberta and British Columbia, which consistently give me reports in the 20s. Most of the RBN reports are from stations in California, Arizona, Colorado, Nevada and Utah.
I think that having a quarter wave length counterpoise running in a fairly straight line really helps the performance of this antenna as does being 10 floors up and away from ground effects. I also think using 30 feet of coax for a choke, as MFJ directs, is very helpful. It was surprising how a few inches of counterpoise length can substantially impact the swr curve and depth.
If you read the reviews for this antenna, you will see a pattern that is consistent with my experience. The higher up, the better. The straighter the counterpoise, the better. The farther away the counterpoise is from ground, the better. So, do those things. Make sure the MFJ soldering and other connections are good. Get the whip as far out into the open as you can. Then have fun.
Not a great antenna but, for challenging circumstances such as mine, a good antenna for those circumstances.
(Original review)
This is a preliminary review, primarily to address other reviewers who could not get an SWR reading below about 10.
I got this for use on 40 meters. I also experienced a flat SWR line at the top of the graph on my RigExpert 30. Very discouraging. However, a little trouble-shooting showed that the problem was with the counterpoise connection. The counterpoise wire was not making electrical contact with the ground connection of the loading coil. Once I sprayed a little WD40 on the connection, it all worked fine. From the balcony of my 10th floor apartment, I got a low reading of below 1.1 to 1, a 90khz wide section at 1.5 or below, and a 155 khz wide section
at 2.0 or below.
During an 0300 CWT session, working from Oregon on 40 meters, I contacted several stations in Texas, California, and Pennsylvania. Admittedly, their antennas were doing the heavy lifting but they did hear me.
Bear in mind, this is an MFJ product. Construction and quality control are not the best. The safety rope was missing from the box. The soldering looks less than ideal. For all I know, the counterpoise connection could stop working this evening.
However, this is a product design that does work and, considering the compromises regarding the size of the whip and the laws of physics, works well.
Time will tell regarding durability. I hope to post an update after a few months use. |
|
| KC9SQR |
Rating:  |
2018-11-12 | |
| Just light your $100 on fire |
Time Owned: 6 to 12 months. |
Absolute garbage. This is the worst excuse of an antenna that I've ever seen. High SWR **EVERYWHERE**. Buy this if you don't like your radio finals and want to blow your radio up. Worst antenna ever made.
I never did get this junk to tune ANYWHERE, ANY power level, ANY band. 10:1 across the board. |
|
| WU6R |
Rating:  |
2017-11-21 | |
| Crap - Never Worked |
Time Owned: more than 12 months. |
A complete waste of time and money. Complete crap. I could never get SWR below 18:1. I can't believe MFJ sells this junk.
----------------------
Earlier 0-star review posted by WU6R on 2017-09-03
I bought this antenna 9 months ago to attach to my 3rd floor balcony rail -- SWR was off the charts ~18::1 on all bands. I checked all connections, rechecked by moving the tap clip from the top "1" coil position to the middle and to the bottom and I still could not get a good SWR. I followed the instructions for counterpoise lengths and tapped coil position, still to no avail. I moved a few months ago and today I got it out of the box and tried it in my backyard on a tripod. Using a RigExpert AA-600 in multi band mode from 40m-2m, SWR ranged from 18.1 :: 1 at 7.00 MHz to 8.1::1 at 50.100 MHz, regardless of telescopic length or coil tap position. This thing simply does not work. |
|
| KB3ZUO |
Rating:   |
2017-11-21 | |
| JUNK |
Time Owned: 6 to 12 months. |
| It picks up only strong amplified regional signals but not very well . the telescoping sections fill up with water when left out as an apartment antenna would need to be , as they do it has worse reception. |
|
| KF3EI |
Rating:   |
2017-07-22 | |
| Not recommended |
Time Owned: more than 12 months. |
I fortunately purchased mine used. First I upgraded the coax since the original RG-58 has minimal outer braid, then I changed the coil attachment to a sturdy stainless clip in place of the tiny copper clip. Next I measured out lengths of counterpoise at .28 wavelength for each band. The antenna nickel? coil has a suspiciously lower q than what is required, and in spite of my mods, almost all the rf current was getting lost before reaching the 3 joint telescoping antenna.
The bandwidth is very narrow below 15m assuming you want to work at SWR <2:1
This antenna just cannot work and consumes too much time and no fun just trying to get out a signal on 90 watts input with 2 w actual output. Contacts were found using WSPR, and occasionally using CW on 20m. I guess that makes sense.
|
|
| K5VOP |
Rating:    |
2016-05-23 | |
| Works as described but poor contstruction |
Time Owned: 0 to 3 months. |
| First off I must say that for my situation this antenna is the best option that I have found. That said, it does work as intended, for the most part. I tested various frequencies' SWR and could get 6-40 around 1.8-2.1:1. (more than one coil wire may be touching the clamp causing higher SWR). The antenna is compact, and very easy to put in my suitcase when I travel (this is what I bought it for). A carry case would be nice, I'll make or find one for it myself though. However, two issues I have with it: 1. first time using it the exposed coax lead that connects to the coil was broken off, very poor soldering job, I had to re-solder it. 2. The alligator clamp that is meant to clamp on the various turns of the coil is TOO large of clamp at the teeth end, I have to bend (spread apart) the coil wires if I want it to NOT touch the other wires and give a higher SWR. the clamp should be narrower at the nose so that you can easily clamp it on a single coil wire without having to bend the other wires away from it to keep them from touching the clamp as well. I am keeping the antenna because, as I said, it is my best option for hotel window antennas that I have found. But I am going to have to remove the alligator clamp and solder on a more narrow one so that I can actually clamp on ONE coil wire at a time. For what it is, the performance is good, the price is fair, but the construction is not so good, 3-4 rating. I shouldn't have to re-solder and exchange parts for it to work out of the box. (If the alligator clamp was more narrow I would probably be getting closer to 1:1 SWR as it wouldn't be touching more than one coil wire). |
|
| KA2DDX |
Rating:     |
2015-08-24 | |
| works well |
Time Owned: 0 to 3 months. |
Hi,
Just thought I'd share my experience from this past weekend - I bought this antenna about 3 months ago and finally got to try it out in a park from a picnic table in a shelter - during a high solar wind day (conditions weren't very good) , and the feed point at picnic table top level - I put it on 20 meters, set the counterpoise wire at 18 feet - the end of the counterpoise was wrapped around a stick about a foot off the ground - tapped the coil 9 down - my mfj tuner got the swr almost flat - and I worked Cuba, Slovenia and Peru - ssb and cw - my first experience with this antenna or any antenna like it - quite surprised - have fun with yours.........
Larry KA2DDX |
|
| KD7ZCI |
Rating:     |
2015-03-17 | |
| Works Well |
Time Owned: more than 12 months. |
| I got this antenna to get onto HF from an apartment and I worked great from my balcony. It comes with a 5.5 foot whip and about 35 feet of counterpoise wire. With some time I was able to get great SWR and signal reports on 40 meter, but I wanted to go lower. I purchased MFJ's 12 foot telescopic whip and used some 75 feet of leftover speaker wire from an auto project to make a longer counterpoise and was able to get onto 80 meters with low SWR and great signal reports, and now I use the 12 foot whip for 80-20 meter operations. Drawbacks: If it gets windy with the 12 footer on, go back to the 5.5 because the antenna does whip around quite a bit. I've had nothing break, but it does worry me. |
|