| WA6JDC |
Rating:  |
2024-03-24 | |
| pretty good antenna! |
Time Owned: 3 to 6 months. |
OK, so I live in a fairly restrictive HOA in So Cal. That said, my lot abuts up to large eucalyptus on a slope behind our home. After considering all my antenna options, I decided that a camo-painted vertical would be my most workable option.
I bought the R8 slightly fearful of the quality issues you may have read about. And indeed, I did encounter them: biggest, was loose parts rolling around the matching box (MFJ did quickly replace it). I also encountered the occasional slightly off holes in the tubing... and extremely incomplete assembly and tuning manual. Well, forget the tuning part - there's almost nothing in the literature to guide one in tuning this 28' Rubik's cube...
That said, and after raising and lowering this thing far too many times... I am happy to say that I got this thing down to 1.1 - 2.5 swr over most portions of bands I use. It's generally 1.1 - 1.5, so not bad.
I have since paired 700 watt solid state amp to my station... so, and FTDX10 to an ACOM 700 watt amp to this R8. I can hear all the DX pile ups, and generally, of course, I can't beat the stations with the big guns. That said, with a little patience, I've worked the world, sometimes with great signals and relatively easily.
For a ham in a modern suburban community... if you can get away with an antenna 49' in the air... this one performs remarkably well. Yes, I'd love to have a nice beam on a tower and a rotator... but life is what it is. This entire shack set up performs truly brilliantly together. Im very pleased. |
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| K6NPA |
Rating: |
2022-05-01 | |
| Very Poor Quallity |
Time Owned: 6 to 12 months. |
Purchased new and assembled. No resonance on any band. Opened the match box. I had to fix open and loose connections. Now resonance on all but 20 meters. Cushcraft Rep said to push the second section all the way into the 1st section. Strange, but directions say 4.5 inches. Did as rep said but resonance is way below 20 meters. Now the two connections for 10 meters is open. Fixed once now it is open again. Poor MFJ quality!
Trying to sale so I can purchase a GAP antenna. |
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| WQ6N |
Rating: |
2022-04-16 | |
| Sharing lesson learned |
Time Owned: more than 12 months. |
| I really like this antenna. For the space footprint it does deliver on all bands. I have owned one for 5 years and have recently experienced high VSWR on all bands. We live in SOCAL and usually do not have high winds or extreme weather other than 100+ F days during summer. I have not guyed the antenna during this time. While troubleshooting the problem, I noticed stress cracks inside of BT1 traps mainly on the 17m coil form and on one side of the 20m coil form. One of the 17m sides was almost broken off. I did a hot glue repair on all the cracked surfaces but and not 100% confident. I found out that one can purchase just the BT1 lower dual trap from HRO. However, I also saw some UV wear on the fiberglass base insulator. The match box looked good but have not taken it apart yet. I did add a missing RF static drain inductor a few years back and that looked good. Parts for these antennas, or even the whole antenna, is hard to find due to current supply chain shortages. I did find a whole antenna at a discount $664 on a online web store (no tax, free shipping). I will replace as much as I can keeping the old material for spare parts. All aluminum to aluminum surfaces are treated with Noalox. The new traps will be additionally sealed with Loctite Sick'N Seal extreme and 3/16 drainholes in the bottom coil boot. All weather seals will have a layer of good electrical tap and coated with black liquid tape. This time I will guy the antenna just below the lower X-Hat to reduce the strain on BT1. BT2 did not show any indications of micro stress crack but I am going to change it out anyway. I do have the heavy duty stainless tilt brackets from DX-Engineering to augment the antenna maintenance. But with the antenna up 12ft in the air, it takes two to raise and lower the antenna safely. Oh, one more thing that I noticed is that the 12m element started to be pulled upward during wind movement separating the 3/8 splice connection which changes the tuning. Those 1/4in clamps barely hold those splice connections. Final input is the light coating of Dow Corning 111 silicon on all the black plastic stand-offs. Looking for another several years of good HF service. Hope this helps others. |
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| HB9IJC |
Rating: |
2021-05-24 | |
| High power on the R8 |
Time Owned: 0 to 3 months. |
After many problems with R-7000 traps and power amplifier, I have now the Cushcraft R-8: very good SWR and no problem with 800 watts CW on any bands.
Edit: May 2021:
My old R8 fell during a big thunderstorm. I then replaced it with an R6000, smaller but without the 30m and 40m. It worked great for 15 years and is still in excellent conditions. Now I have a new R8.
The R8 is truly the best multiband antenna I have ever seen. The one I bought in 2021 is still different from the one in the 2000s.
First the tubes are reinforced with other tubes inside. This makes it much heavier than the old model and poses real problems for installation in difficult places. Then in the first SWR measurements I made the 20m and 30m bands resonnance frequency much too low (13.3 MHz and 9.8 MHz). I had, following the advice of the manufacturer's technical support, to remove 6 turns of the 20m winding in the BT1 trap. Then it is advisable to cut the tips of the traps screws because they are very close to the central tube. Once properly installed and properly adjusted the R8 is really excellent.
73, HB9IJC |
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| ON4VP |
Rating: |
2021-01-30 | |
| Performance is great, build quality is poor |
Time Owned: 3 to 6 months. |
A long time ago I installed the R-5 on a rooftop and it performed outstanding. A friend of mine had both the R-6000 and R-8 and raved about it. So after several years of doubting I made up my mind and got myself a new R-8 model 2020.
The moment we (my buddy and me) unpacked the antenna for inspection and assembling my buddy noticed that materials were changed. The network was different, the spacers for the stubs were different and both coils were different (I come to that point in a moment).
We started to build the antenna. First obstacle was mounting the network to the antenna (hot side). The hole of the bracket didn't match the hole drilled in the tube (lower antenna part). So we had to enlarge the hole in the bracket to a point that the bolt became a bit to small to have a solid contact with the bracket. Some washers and slightly bigger bolt did the job.
When assembling the stubs the run along the central tube we noticed that the spacers where to tight so we had to put the stubs through the holes with a little force. (this resulted after a few months in a situation where after a windy night the 12m stub was broken in two at the joint of two elements because of the bending of the whole antenna. Since the holes in the spacers were a bit to tight we came to the conslusion that there was not enough flexebility so that the stubs could move when the whole antenne bends in the wind). Since wheater has been bad, the 12m element still has to be fixed.
Another strange problem occured after the first rain (after errecting the antenna). We saw water dripping out of both coils and SWR was sky high on 30 and 40 meters. Lowering the antenna and after some inspection we made a small movie and sent it to the vendor. He told us the antenna came with coils with caps on both ends and that was not supposed to be. Only top caps were needed (my buddy also referred to his antenna with only top caps on the coils) so the vendor told me to cut off the lower caps (I asked proof by email for my warranty). So we removed the lower caps of the coils and a glass of water came out of the coils. After some emails we were told that the put coils from a yagi in the box ???? Weird explaination but the coils now seem to work as advertised.
Last (only after 3 months of installation) I start to notice corrosion. All the screws that close the network plastic housing are rusted. Also the radials are corroded and rusted at the lower end (where raindrops keep hanging and dropping off the antenna).
It left me with a mixed feeling. Would I advise this antenna to another ham? I don't know. Performance wise this is a great antenna. The low angle take off does work. I have better results compared to other verticals and low mounted dipoles. On bands that are open at the moment (40/30/20/17) I get very good dx results, lower noisefloor than 1/4 groundplanes so I'm really happy with the performance of the antenne.
The problem lies in the manufacturing and finishing of the antenna. The quality has changed when MFJ took over Cushcraft. If I see the R-8 of my buddy after over 12 years, it still looks in great shape. Mine (only 6 months up in the air) show rust, corrosion and had wrong coils, louzy drilled holes and spacers totally different from former revisions that are way to tight for the stubs.
I still have to alter the spacers to give the stubs a bit more flexability in windy conditions and have to take care of new stainless steel screws and brush the radials and protect them against rust.
So finally, yes, I will advise a ham to buy this product for his performance but will make him or her aware that the manufacturing is poor and not at the level of previous revisions made by Cushcraft in earlier days. So if you want are willing to improve some things and take the poor finish for granted you will be having a good time on the bands with this R-8. If you are looking for a top quality product, look elsewhere.
Picture of installation on my qrz.com page. Keep safe and enjoy radio. Phil ON4VP |
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| K0GZL |
Rating: |
2018-12-23 | |
| The R8 is ok. |
Time Owned: more than 12 months. |
During my 62 years of Amateur Radio, I have found that vertical antennas are great for low takeoff angles to secure that elusive DX.
If you read the reviews on commercially made verticals and also beams, so many people complain that they don't work properly some of the time. I have never had any trouble with verticals or beams if I read the manual and follow the assembly instructions closely.
However, over the years, I have found that there are other things that can enhance the operation, reliability and longevity of any antenna that especially uses metal tubing such as Aluminum.
Remember this; Aluminum oxidation starts forming as soon as the tubing is manufactured and ... Aluminum oxide is an insulator. I would say that over 90 percent of antenna problems are due to mechanical and/or electrical bad connections.
Here's what I do when assembling an antenna right out of the box:
1. Get the electric drill out and install a large bit into the chuck.
2. Wrap a pad of fine steel wool around the bit and ream out the inside of the larger tubing into which another piece of tubing will slide and... also buff, with fine steel wool, the outside of the smaller tubing that will slide inside the larger.
3. This is important: Buy a tube of "CONDUCTIVE GREASE" at the hardware store; do not use dielectric grease. Grease up the inside and outside of the Aluminum tubes and other parts that are to be fit together; this will guarantee a good electrical connection for sure; no need to over-do-it on the grease, though !! Cleanup the excessive grease with alcohol.
4. One weak mechanical and electrical situation with the Cushcraft R8 and R9 verticals is that the ends of the trap coils are brought out and wrapped around small hex sheet metal screws to the trap cover; this is asking for a bad connection, oxidation and intermittent operation. Purchase some Aluminum flat washers and lock washers and use them to produce a solid contact but don't over tighten the screws; don't forget to steel wool the connection and use the conductive grease first !
5. Last but not least !!!!
Verticals have a tendency to get water inside the tubing and traps. The plastic, trap covers, often crack or split with age; water can ooze into where the tubing pieces slide together or where various screws run thru the tubing.
A sure fire cure for water problems is a product that I use, called "Through The Roof" made by a company called,Sashco. It is a clear rubbery liquid. You can paint brush it on all those connections that have been steel wolled {Sp.?} and greased and ... don't forget the plastic trap covers and misc.screws. It does not harden like epoxy, so you can pick or scrape it off if you need to adjust your antenna settings; Good stuff.
73s, Bob K0GZL
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| K6JMQ |
Rating: |
2018-02-18 | |
| Worth the Money |
Time Owned: more than 12 months. |
| I have had my R8 in service for about 3 years. I'm on the SoCal coast where salt air is a problem. I'm also on a residential lot with no space for radials on the ground, I operate on phone, CW and digital modes on all 8 bands at 100W max. Assembly was easy. All the parts were there and fit correctly (with a little tweaking). The antenna is mounted on a 16ft 2" galvanized pipe attached to a the factory tilt base assembly. The tilt base is mounted to a 4ft section of galvanized pipe set in a 3.5 x 2ft concrete base. Because we have a strong sea breeze everyday I used the 3 point guy wire kit. The antenna has performed well on all bands and modes. 40M is very narrow so I tuned it to 7.175 and my AT2K handles the tuning elsewhere. I don't need (although I still use) a tuner on the other bands as the SWR is good (1.5 to 3.0) across the bands. Over-all I would say the antenna meets my expectations and performs well considering the limitations I have here in SoCal. I've worked 110 countries on it and all 50 states. I get very good signal reports from it. Yes its noisy on RX, but that was expected from a vertical. Upon initial installation, I placed the antenna too close to my house. The radials were less than 3ft from the roof. After testing, I found by relocating it so the radials were 8ft from the roof, the SWRs were much better. This might have been because there is a metallic material (granules) in the composition of my roof shingles. Over all I would say the R8 meets my expectations. I didn't give it a 5 as during the assembly, I had several questions for Cushcraft and I was surprised to find they didn't have the answers. This puzzled me as they have been producing this antenna for years. Would I recommend the R8? Yes, if you are dealing with space restrictions. If I were to do it over I would get the R9 and have 80M. |
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| VK3YP |
Rating: |
2018-02-06 | |
| Mechanically Poor |
Time Owned: more than 12 months. |
Assembled a MFJ manufactured R8. The tuning stubs needed double hose clamps or else they would slide apart when the R8 was moving in the wind. Guyed at two levels but the 40M trap went faulty after about 2 years due to the 'whipping' of the top trap element in the wind.
Performance was excellent on all the bands 40M to 6M with low SWR.
Haven't bothered to take down and repair/replace trap so might just junk the entire antenna instead.
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| VR2AJ |
Rating: |
2018-01-02 | |
| Needs handle more-loading power |
Time Owned: more than 12 months. |
What’s unwanted experience had been happened in last year, of course, talking about the lovely star of Cushcraft R8, I would to say that 2 trap coils have totally burned by the normal CW mode with my current liner amplifier (Tokyo Hy-power HL-1Kfx). I have tried to order those spare parts of trap coil (BT1 & BT2) from MFJ by 2 different times, but they have rejected my orders without reasons. That’s fine forget it, I’m going to consider other brand’s vertical antenna in the market, hopefully, coming back to the radio soon.
Don’t put too much output power on this product, less than 500watts CW mode will getting safety.
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| KN6SU |
Rating: |
2017-05-05 | |
| Bandwidth on 40 |
Time Owned: more than 12 months. |
Follow up to last post:
Used the Rig Expert AA-230Z (new gadget...highly recommended) to reset the 40M tip element and set the SWR min at about 7.23MHz and got the 2:1 range from 7.150 to 7.290. The SWR graph is fairly symmetric but steep on 40, so if you want to use it w/o an ATU you really need to set the min SWR point carefully in the part of the band you want to do that. My MFJ-986 easily handles the slight mismatch below 7.150. 30, 20, and up are fine across each of those bands.
BTW, the AA230Z makes it super quick and easy to check and tune multiband antennas like the R8. Last time I used my MFJ Analyzer...it did work but the Rig Expert analyzers, with their graphic and other features make this sort of work almost enjoyable.
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Earlier 5-star review posted by KN6SU on 2013-07-16
I got the R-8 in 1998 and it's been mounted on a 5' section of galvanized pipe attached to the peak of my roof (25' up). I've had it down for maintenance 2 times since then, when for various reasons it developed very high un-tunable SWR (>25:1 on all bands per the MFJ analyzer). In both cases the problem was in the MN-8 matchbox. The MN-8 is a simple unit that contains two wound toroids and a blue disc cap. It makes electrical contacts with (A)the upper radiating section of the antenna, (B) the ground plane clamshell ring, and (C)the base. A & C are connected with aluminum brackets and B is connected via a wire flat braid. You'd think it should be bombproof, but it isn't. The brackets get oxidized and need routine cleaning. That can be done without opening the MN-8 box. However, I found I couldn't fix the problem and I opened up the box. The first time I did that I found the problem was poor soldering at the center coax connector and fixing it got another 3 years of good performance. When it crashed again, I opened the box, but couldn't see any obvious problems (on the "front" side of the board, so I removed the board from the box and, voila, found that one of the lower toroid wires had detached from the board! Easy to resolder. The other joints looked intact, but just to make sure I resoldered them as well. The R8 now works as well as it did in 1998.
As others have said, this is a multiband HF vertical, and such antennas represent compromises. My previous vertical was a Butternut HF-9 (used the 80m add-on kit and radials). I liked its being "trapless," but it was a very noisy antenna and required lots of real estate for the radials. I found that the R-8 worked just as well (and better) without the need for a radial system. Both required an ATU to get SWR down to 1:1. On 40 and 20, you can get 1.5:1 w/o an ATU, but you need to space the antenna segments where you plan to operate (either CW or SSB band segments)because the resonant bandwidth on 40 and 20 is fairly narrow. I set mine at the middle of the bands and use the ATU to get the best match that I need, since I operate both CW and phone. 20 and 17 seem to be difficult to independently tune mechanically (shared trap?), but an ATU works there when the R-8 is mechanically tuned to mid-band on 20.
Bottom line: I've had the R-8 for 15 years. When it works, it is a fine multiband vertical HF antenna that sets up over a very small footprint. I don't know about the MFJ version, which may use some less durable hardware parts according to some of the posters. All the hardware (clamps, bolts, etc.) that came on mine were SS. I don't know if MFJ has changed the aluminum Cushcraft used for the elements or the traps, but mine has stood up fairly well. Aluminum is what it is, and needs occasional cleaning. Last time I took the antenna apart I used Loctite C5-A copper based anti-seize compound between the elements, which seems to make a good electrical connection and protect from corrosion. I recommend it when you first assemble the antenna. Finally, the MN-8 is a potential source of serious problems, and you should always suspect it if you develop high SWR across the bands. The good news is that it is easy to repair. |
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