| WB2VUO |
Rating:  |
2023-11-05 | |
| Too Flimsy |
Time Owned: more than 12 months. |
Too flimsy. I live next to Lake Erie, not on the shore but within 5 miles. The first winter stretched all of the wires and the slack had to be taken out. The second winter killed the antenna with 4 of the 5 bands breaking in the winter winds. My solution was to rebuild it with stranded Copperweld.
I had to modify the wire anchors and went with UV-resistant wire tiedowns at all the crossing points. I also added lugs to both ends and fastened them down with just enough slack to accommodate my local winds.
All the lengths had to be readjusted, a tedious job, but well worth it. The antenna is now tuned to the low end of all the bands and no tuner is required anymore. I added 6 meters to it, but the 6 meter performance is very poor (Might be out of the balun range? IDK...)
Now that it's rebuilt, the performance is noticeably better. The antenna is mechanically stable, and this is the way that MFJ should have done it the first time! ALso, the fiberglass arms weather poorly. I have painted them to eliminate the glass shards that are just waiting to stick in ones hands...
IF you are buying one, and your climate allows, it's a good choice. If you like to rebuild after the storms, this is the antenna for you.
If you want to install it and forget it, look elsewhere. YMMV, but it's been an interesting trip.
DE WB2VUO |
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| W7ARE |
Rating: |
2023-04-16 | |
| Decent parts and fitment but… |
Time Owned: more than 12 months. |
| I bought this new a couple years ago. I have several verticals and thought I’d enjoy trying something different. (I didn’t have any need for it til the bands heated up just now due to the new solar cycle in case you wonder why it took so long!) I opened the box, read the little instruction booklet, made sure everything called for in the booklet was present. It was. Then I began assembly. Easy, even for me! Until I got to the 20 meter elements. The two wire elements were approximately 5’ short. I checked the booklet again. I strung it just as shown, where shown. There was no way these two wires could stretch enough to come together at the center insulator. I did the calculation. The two wires should each be in the neighborhood of 16’8” or so. The two wires provided in the packet marked “20 meters” were each 14’2”. What the hey, MFJ? So, tomorrow I am off to Home Depot to find some suitable wire! |
|
| K0DXV |
Rating: |
2021-03-27 | |
| Minimal Quality - Excellent Performance |
Time Owned: 6 to 12 months. |
I bought this antenna several years ago. It remained in storage until last summer when I decided to set it up and see what it could do. I did not like the wire so I replaced it with insulated 14ga antenna wire from DX Engineering. I did not like the way the wire was held to the fiberglass arms so I used black, UV-resistant wire guides I got from All Electronics. These wire guides were simply attached to the arms with the provided screws.
The quality of the parts is barely adequate. For the money charged, MFJ could do a lot better, especially how the wire is held in place on the arms - which is just crushing them under a washer. This method could lead to easy breakage after enough weather. The wire supplied is very thin. I did not feel it was sufficient for full power so I replaced it.
The system uses two square, aluminum plates to hold the arms in place. Two stainless bolts secure the support arms. There is no hole in the plates to allow the mast to protrude through the top so you cannot add anything above the antenna or add lines to support the arms. I intend to change this next summer. Cutting holes in the plates and extending the mast above the antenna would allow the use of support lines to stabilize the arms.
I am somewhat suspicious of the balun - but so far it seems to be working correctly. I bought a very high quality balun with the proper ratio (50 ohm feedline input - 25 ohm output to the antenna -- DX Engineering) , but it is too heavy for the current configuration. Once I cut a hole through the mounting plates to allow support lines I will install the new balun.
Assembly is somewhat complicated. There are a lot of wires to route around the arms. This is something to take plenty of time doing. I expected the final tuning steps to be, as the Brits put it, fiddley. But, surprisingly, it only took a few adjustments to get each band tuned. Easy to do with a little simple math: 468/current resonant frequency then subtract 468/desired frequency - assuming you started with the wire slightly long. Do the reverse if its to short. But, basically, determine the difference in lengths from desired and observed, divide by 2 and add or subtract wire to each end as needed. Adding small pigtails to increase the length is not a problem. It took me no more than 2 tries to get it right. I did the assembly and tuning on my second floor deck approximately 15 feet above the ground. I would recommend testing for resonance on each band with the antenna as high as you can manage and at least 10-12 feet. Otherwise, you might find that resonance at your working height to be different than what you tuned.
Now let me comment on the overall design of a CobWeb antenna. This is, very simply, a unique, even brilliant design: compact (< 10' per side), light (11 pounds) and mostly omnidirectional antenna that covers 5, 6 or 7 bands depending on the model you have. What's not to love?
Mechanically MFJ does what it always does. Quality is just barely adequate. Fortunately, what you get is easy and inexpensive to upgrade with more robust parts. It needs better wire, a better means of attaching wires to the arms, holes through the mounting plate to allow support lines to the arms - especially if using a 40 meter radiator, and a better weather sealed, structurally stronger balun.
Finally - how did it perform? I mounted it on a heavy-duty 38' MFJ telescoping mast. I did not use the two top sections that were just too light weight. This puts the antenna at about 25'. I wish it were higher. But that's all I could do with what I had on-hand. I guyed the mast in 2 places with 3/8" Nylon/Rayon support line. It's survived wind storms greater than 60 MPH, Heavy snow, and driving rain. It still performs perfectly.
The actual performance results are exactly what I expected. This is basically 5 dipoles folding into a square. Each band shows excellent SWR bandwidth. It is a quiet antenna. It seems somewhat resistant to picking up random noise. At only 25' it's a bit low for good 20 meter performance. nonetheless, it hears surprisingly well. On 17 where it is a half wavelength above ground it does a great job. 15, 12 and 10 haven't been very active but I expect it will perform very well on these bands. I always start with the CobWeb when I scan the bands for activity. If I need more gain and better elevation I switch to the beam. But, often, the CobWeb is all I need. Being quiet and omnidirectional has a big advantage.
If you are space-limited or just want an antenna that has multi-band versatility, this is a GREAT choice. |
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| VY1WUD |
Rating:  |
2020-05-10 | |
| Balun box is junk |
Time Owned: more than 12 months. |
| We have gotten the New MFJ 1835-H model. The balun is poorly build had to rebuild the whole thing. The insulators are really thin and looks like it can break easy at -40ºC. We believe MFJ have extremely cheap parts. MFJ = Major Floppy Junk. MfJ will not honour their warranties tried many times to talk to them.. NEVER BUY MFJ! |
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| W6MVS |
Rating: |
2019-07-17 | |
| QC issues with Balun |
Time Owned: 0 to 3 months. |
After assembling the 1835H, I just could not tune any of the bands. SWR would show infinity. I suspected the issue was in the Balun box as others have reported being able to tune this antenna. I dissembled the box to find that there was too much of the insulation removed from the center conductor of the coax where it was soldered into the board that was causing a direct short between the center conductor and the shield.
I gently moved the ferite rings out of the way to expose the coax connection. I covered the center conductor's bare wire with a plastic flexible epoxy and let it dry. This would now insulate the conductor from the shield. I reassembled the box, connected all of the band wires and now was able to easily tune all of the bands except 6 meters. I already have a tri-band vertical with 6 meters so I wasn't too concerned about 6 meters on the cobweb and didn't waste a bunch of time trying to tune it.
I deducted one point due to the poor quality control. Otherwise, I'm happy with the cobweb antenna. |
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| KC9NCS |
Rating: |
2019-06-08 | |
| Received A Hot Mess of an Antenna |
Time Owned: 0 to 3 months. |
Not sure where to start this review. Moved from the big house with the big tower and downsized to a townhome out of necessity (declining health, unable to take care of big house and tower anymore...) so I decided to give the 1835-H a try after reading all the positive reviews.
Everything looked good in the box and assembly began, taking about an hour to put things together and get the wires installed. That's where the trouble began.
The eyelet for one of the 20m wires came off in my hand. Getting a new eyelet and a crimper and soldering the connection was easy enough to fix.
Tried to tune 10m first per the instructions to no avail. Couldn't get it to go above 27.995 to save my life. Said screw it, let it be and figured I'd use my tuner for 10m should I ever use it.
Same problem on 12m. Can't get it to tune anywhere in the band and yes, I'm using the wire labeled 12m.
15m tuned right where I wanted it. So I went back to see if I could get 12m and 10m tuned - no such luck.
17m tuned right where I wanted it. Tried 10m and 12m again - no luck.
20m next. No luck. The wire sent was far, far too long and drooped excessively. Measured the wire and saw it was more than three feet too long.
At this point I don't want to clip it, I just want to box the thing up and return it. Unfortunately I purchased it three months ago and had to wait for a friend to install it in my attic for me. I'm very disappointed the antenna only works on two bands for me. I followed the instructions to the letter and used my MFJ Antenna Analyzer to try and get this thing dialed in for almost four hours.
I just give up on it. If I could get 15m, 17m and 20m tuned on this thing I'd be happy and would give it a good review. I just can't. |
|
| G0UZJ |
Rating: |
2018-11-11 | |
| A fantastic compromise antenna |
Time Owned: 3 to 6 months. |
Review of my MFJ Cobweb
Here in FL I do not have many options for antennas due to various restrictions. I had a dipole in the attic/loft but it was very disappointing.
A couple of local amateur radio stations told me that their cobweb (from another manufacturer) was a great antenna and suggested I consider one.
So a decided to buy one from DX Engineering who offered the best price delivery options. The package arrived and I started to build. Putting it on a pole made assembly a lot easier.
I did query the Balun with DX Engineering, the instructions showed two bolts for my high powered version. However that is how they are now made. My guess is a cost cutting exercise resulted in a single bolt, which resulted in it having to be adequately secured with an addition of a zipper tie. I also had to make a modification to allow it to sit further down on my pole as I have a colinear above it. None of which were difficult to accomplish.
On the day of the installation a couple of friends helped one came armed with his MFJ antenna analyzer which made tuning easier - be careful and only make small snips/cuts as it is easy to overshoot the desired resonant frequency. On one band I overshot and I had to solder additional wire back on and start again.
The antenna is mounted on a small 25ft telescopic pole bolted to my pool enclosure. It is fed with 100ft LMR400 buried underground. The 2:1 bandwidth is not too wide so I use an ATU. On the air I immediately noticed how quite the background noise was (<-120dbm) and signals are fairly good (but not as good as a multi element beam at 200ft).
Another local amateur using a MFJ cobweb told me his signals increased >10db by raising his mast from 20 to 30ft.
Am I pleased with it? YES - I have now worked more than 100 countries in 5 months mainly using 20m and 17m. It was much easier to put up compared with my A3S and Rotator. |
|
| K7LRB |
Rating: |
2018-09-04 | |
| Works "as advertised". |
Time Owned: 6 to 12 months. |
I actually purchased the model 1836 but there is no place to 'review' an 1836. The 1835 is the same antenna minus 6 meters. The two are virtually identical with the exception of the addition of 6 meters on the 1836.
As a 'baseline': I have been a ham for about 58 years and for the VAST majority of that time I have been a "wire antenna" guy. So keep in mind, when I bought the MFJ-1836, I was not looking for a 'replacement' for a yagi. I aslo considered some of the 'spider beams' but opted for the "cobweb" because, primarily, it requires no rotor. It is also much less expensive than any of the spider beams. So, I was not expecting yagi performance.
Another thing to keep in mind is that, although ham radio has been a lifetime hobby, I am not a contester, nor a 'DXer', nor a 'paper chaser' of any kind. It is, and always has been, a very casual hobby. It has always been fascinating to me, can be a 'stress reliever', and is just plain FUN.
To the "cobweb". Assembly: Assembly is straight forward, simple and with no "gotchas". One thing I did do was use my own stranded copper wire, same gauge as that provided by MFJ. It looked to me like the wire provided by MFJ is "mystery wire". To this day, I am not sure 'exactly' what it is made of. Yes, I know, wire is wire, as was pointed out to me by other hams. Still, in my 'pea' brain, copper is better for antenna wire than, well, whatever MFJ provides. Nothing against MFJ, I have no reason to doubt that a cobweb with the wire provided would not work just as well as my copper wire. In the interest of "full disclosure" I just wanted to mention that I used copper wire in place of the wire provided by MFJ. Yes, this meant I had to cut my own wire; no problem, I just cut each wire to the same lengths specified by MFJ.
One other thing I did was to NOT let the ends "hang down", as suggested by MFJ. I am sure it would work just as well, I just don't like the idea of wires just "hanging down" from ANY antenna. So I did take extra care to carefully place the 'insulators' so that once the 'trimming' was done, the ends would lay flat and along the 'insulators'. Just looks "neater".
I took my time assembling the antenna, and, eliminating copious 'snack breaks' and other, ahem, interruptions, I would estimate the build time to be about 4 hours or so. "Quick and dirty" would take less time. I assembled the antenna on a short (5') fiberglass mast and 'tuned' it at the same height. I don't understand why all the 'complaints' about tuning this antenna. Now, I DO have an antenna analyzer (an MFJ 259B, GREAT antenna analyzer) and perhaps this has something to do with other's negative reviews on this. Not sure why you would build, or work on, ANY antenna without an analyzer. Anyway, tuning was quick and easy, and I noticed little to no interaction between the bands when tuning any other band. I easily got ALL the SWR readings down to 1.1 to 1 MAX on each band.... EXCEPT 6 meters. I simply could not get 6m down to less than about 1.6 to 1. I did NOT spend a whole lot of time on 6m. Perhaps if I had "Jacked" with it enough (moved the attachment points, etc), I could have gotten it down more, just was not worth the effort (to me). When the antenna was raised to it's final height of nearly 30 feet, I noticed negligible change in SWR on any band.
Operation: Again,I refer you to my initial statement about 'casual' operations. Most of my antennas over the years have been wire, primarily dipoles/inverted vees. What I first noticed about the cobweb was that I seemed to be able to 'hear' more stations. Subjective? Of course. But I did quite a bit of A/B testing and that appeared to confirm my initial reaction. I can't give you any "measurements" and of course, conditions vary a lot, often in a very short period of time, same QRG, same time frame. I can only say that I noticed anywhere from 'very little' difference between the 'cob' and the dipoles, to as much as a 2 S-unit gain. Take that for what it's worth.
Bottom line: I am certain I could build a "better quality" cobweb antenna for significantly less money. HOWEVER, I wanted to get something that was "ready to go". I did now want to go out and find all the individual parts, fiberglass poles, insulators, matching network (balun, bought or built), etc. Other than providing my own wire, which I already had in my "junk box", everything was provided by MFJ; 'pop the box', "some assembly required", 'tweak it' and put in on the air. Buddda bing, budda boom. Easy peasy.
One other thing. I do have the antenna mounted on a fiberglass pole. Not sure it that makes any difference from putting up on a metal pole, but that is what it is mounted on. I have one set of guy ropes and the antenna has survived winds of up to 50mph with no discernible change in performance.
So yeah, I am very comfortable giving this antenna a "5". It does what it says, "as advertised". A kid could put it together and (maybe an older kid) can tune it up. Stick it up on a pole and make contacts, as in, HAVE FUN!
If you are considering a 'cobweb', I hope this helps. Please feel free to email me if I can be of any further help. My info is good on QRZ, et al.
73,
Larry |
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| KC7YE |
Rating: |
2017-12-03 | |
| Still OK |
Time Owned: 6 to 12 months. |
After about 6 months use, still pleased.Antenna has survived 60 + MPH winds with no damage. Condition still don't allow for a real A / B test but better then expected. Do to band conditions have been on the JT / FT modes and working some DX. Have one issue ( that I don't understand) : No rain SWR is in the 1:1.5 range on all bands, rain in heavy amounts SWR goes to 2.0 or so, lite rain is in between . SWR goes back to "normal" as soon as rain stops. Have only had one neighbor comment and she didn't care as her dad had been a ham.
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Earlier 4-star review posted by KC7YE on 2017-06-21
Moved to a "new" QTH about a year ago and have been running EFW (end fed wire) on HF with OK results until this last spring when conditions went south. Really wanted a beam but thats not happening also want to keep a low visual profile. Know one guy down in Oregon that has one and talked to him, bought on his recommendation. So around first of May antenna arrives, assembled in garage ( raining ) and tuned per instructions for the CW end of bands. Was pleasantly surprised by the quality of metal work and hardware, instructions are good. Works as advertised at 20ft and if there is any propagation is much better then EFW. Of course conditions have gone even further south so have had no real test or A / B comparisons. Antenna might be a "5" but I don't rate anything that way. |
|
| VA3FLF |
Rating: |
2017-09-11 | |
| Pros and Cons |
Time Owned: 0 to 3 months. |
Well, I needed a multiband antenna that was affordable and fit my needs for limited space. The MFJ Cobweb filled the bill for that purpose. I got it mounted on the roof of garage with a Rohn tripod and it works fine. As matter of fact, we had several days of high winds and a squall line go through and it stayed up fine wires and spacers are all good. I got the H model and the manual stated to make a balum out of looking the coax. This was impractical using RG8. I called MFJ and got the "antenna guru" immediately. He said I can use a 1:1 isolator instead. I installed that right at base of tower on feed line and it is working fine. With the band conditions as they are, its very difficult to say how well it is working, but I have made a few DX including HI from here in Ontario.
Negatives: This thing is a bear to tune. I went through several, I mean several iterations of tuning. I thought this was going to be easy on my first time through but discovered 17M was low out of band. After adjusting 17 back up, all the other bands were off. I am a digital guy, so I was shooting for low end of bands. After its all said and done, I could never get 20M better than 1.2 SWR. 12M is a bit high as well, but the other I have 1.1 and 1,0. I would not recommend this antenna unless you have an auto tuner on rig, or external. The bandwidth is just too narrow without an external tuner.
So overall, good for price, size, and as far as I can tell performance. I think some improvement could be made on the tuning spacers and screws to make it a bit more durable and easier to tune. |
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