| KA1TY |
Rating:  |
2015-08-10 | |
| Good rx/tx if grounded, build quality is lower |
Time Owned: 0 to 3 months. |
I purchased this antenna after reading a lot of reviews here & elsewhere. I knew about the issues with grounding, and I did run into them, but managed to get it to work.
On V/UHF this antenna is a breeze - covers the whole band under 2swr w/ very little tuning, tx/rx very well.
6m & 10m - MUCH more narrow, and bond! bond! bond! But once you get that done, you should be ok. I do recommend an NMO/drilled hole mount, even tho that wasn't possible for my car.
I did have some swr issues on HF b/c my old swr meter is apparently bad. Tested at 1.5 for 6 & 10m, but then I noticed my tX power was folding back. Got my hands on an analyzer, and found the SWR was much worse. I spoke w/ Mark at HRO who was GREAT! Helped me by interfacing w/ diamond & getting me pointed in the right direction - grounding/bonding. Took me a while to get it, but once I did, the antenna was tunable, although a much more narrow range on 6 & 10. But I could live with that.
Here's where I have problems.
Wayne, the Diamond Rep, was asked by Mark (HRO) to contact me directly multiple times starting in July. It's now mid August. I've still not heard from Wayne/Diamond directly. Also, at first I thought I had a bad 10m coil (due to the bad swr meter). Wayne/Diamond originally said they'd just send me a new one. After a week or so of waiting I asked about it, and Wayne/Diamond had changed their mind. Granted, they were right - bonding was the issue. But I shouldn't have had to check in on it to find this out as something different was promised.
As to build quality - I drive a 98 outback w/ dual sun roofs. Drilling a hole isn't really an option, and I won't use a trunk lip mount b/c I often operate w/ the tailgate up. So I used a diamond K515S luggage rack mount. Managed to get the rf ground to work once I knew the issue. But just yesterday, the antenna itself simply fell off. It didn't break at the luggage mount (I'd blame the mount if so), but just below the tilt-over section, which I checked every cpl of days b/c I'd noticed it has a tendancy to loosen up. I never use parking garages, I don't have a carport. Maybe a drive thru sometimes, but it's on the passenger side, so rarely if ever hits.
Pictures: http://imgur.com/a/fQ5M2#3
I have yet to contact Wayne/Diaomond on this, but I don't expect anything positive to come from it. So ~$100 out the window.
TL;DR - Good if you ground it properly, use a known good analyzer. Can't recommend it for mobile - mine broke. |
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| KF6NTE |
Rating: |
2010-01-27 | |
| Great Mobile Antenna |
Time Owned: more than 12 months. |
Just wanted to update on my recent continued use of this underrated antenna with the 20m and 40m coils installed at the same time (40m coil on top, 20m perpendicular).
I have it hooked up to my IC7000 through an AH-4 to help increase the usable bandwidth. On 40 meters I can pretty much tune from 7.150 all the way to 7.300 under 1.5:1 and the entire voice band on 20m. I have been able (and continue) to make mobile HF contacts from Hawaii and Alaska to Florida on 100 Watts. I am checking into 40m nets and ragchewing all over the country almost daily from my car during the commute traffic without a problem. Just follow the mfg recommendations for grounding and you will be fine. The AH-4 is a great little tuner. 100 watts is all you need. Keep it simple and have fun !.
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Earlier 3-star review posted by KF6NTE on 2009-08-15
Nobody said this was supposed to be a perfect antenna. No antenna design can claim that. Even the most efficient antenna compromises some aspect of operation. The trick is to be able to understand the limitations of the design and work with them to formulate informed expectations and obtain adequate results.
This top-loaded antenna design requires a good RF ground and bonding to get the 1.5:1 SWR out of it that the spec says it supports but the limited bandwidth can be expanded with the use of a tuner or an UNUN. I've been able to reach HAWAII from California using the 14Mhz coil and 20Watts and I am SURE most of those 20watts went into efficiency penalties BUT I made the QSO and that fulfills what my expectations were. So this is a reasonable HF mobile antenna for the higher bands if you understand its limitations. It's not the best or most efficient antenna but considering all the complications required to operate 100% efficiently, this is a good compromise design. Don't be in a hurry installing this antenna, the most tedious part is to get all the grounding and vehicle bonding done correctly. Do check it periodically for loose screws. |
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| AI4HO |
Rating: |
2009-06-13 | |
| Like it very much!! |
Time Owned: 6 to 12 months. |
Just wanted to say that this being my second HV-7A, the 1st one I mistakenly sold. I know, I know, this is a compromise antenna at best, knowing that going in, I have had nothing but positive experiences with both my HV-7A's. For several months my HV-7A rode on top of my truck, that is until the mobile HF bug bit for the third and final time.
I have used the HV-7A on my FT-8900, then on the 706MKIIG. Never did get the other loading coils for the antenna. But since buying the Tar Heel 40A, haven't had the need to, but that doesn't mean I wont, hurricane season is upon here in south Florida. Might be nice to have them on hand, cause I know that the 40A WONT be on my truck in the event we get hammered this year.
I think the most positive experience I've had with the HV-7A was in Mexico about 3 years ago, using a Yaesu FT-817ND and theDiamond HV-7A. We had an afternoon to ourselves,it was then I remembered the Treasure Coasters Net that used to meet on 14.187.5. Had some time trying to find a suitable spot to mount the antenna, finally found an old chain link fence about 5' high, with the couple different types of mounts my friend included with the antenna he loaned to me for the trip. Got the antenna mounted, hooked the coax to the 817 tuned a bit, heard Freddy KD2XD in Ft. Pierce, Fl. calling for checkins. I answered, took me a couple of tries, as Freddy was in his mid to late 80's at the time. Well Freddy did hear me I was light to say the least, but from Vera Cruz Mexico to Ft. Pierce, Fl which is a considerable distance with 5 watts and the Diamond HV-7A. Yes I do like it very much. |
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| KL7IPV |
Rating: |
2009-03-12 | |
| it is okay, but...... |
Time Owned: more than 12 months. |
I bought the antenna thinking light would be good. It isn't but it is okay. I used mono line to keep it from blowing backwards as I traveled the freeways. I don't like getting out to change the 20 meter coils for the 40 when I want to change bands. After using the Hustler with 80-15 meters without needing to change the coils, I built my own antenna. I use my "Antenna-To-Go" now and run all the bands with a tuner and I am not worried about it falling apart either. I still use mono line to keep it vertical when driving the freeways though.
Frank |
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| KD7CAO |
Rating:  |
2009-03-12 | |
| Design Flaw |
Time Owned: more than 12 months. |
| Well during the past three years of ownership on this antenna I must say I have been thoroughly disappointed. The first disappointment was that there were no mounts available that adequately supported this antenna, the second is because this antenna is so inherently heavy. I had the first antenna for about 18 months, always had to check to make sure it was tight to the mounting bracket I made. The problem was that the antenna cracked at the Black Resin Ring just above the PL-259 body. Replacement parts cost $50.00 plus s/h. I fixed it and moved on. Then today I'm driving down the road and I hear a blare of an airhorn and notice that my antenna has broken off and is being ran over by an 18 wheeler. My $140.00 antenna plus the $50.00 for the replacement is now a pile of mess in Corinth, TX on I-35E. I must say that it was a disgusting displeasure to work with Diamond last time, I sure hope they work with me this time. I want to point out too that it scratched the side of my truck as it broke off. Not to happy about that either but hey it is a truck. |
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| KU4AA |
Rating: |
2008-06-06 | |
| Prone to problems when older (but aren't we all?!) |
Time Owned: more than 12 months. |
I've had my HV7A for nearly 5 years now. After 4-1/2 years of use, the Loading Coil/Foldover Assembly (the "base" that several reviewers have alluded to) sheared off at 70 MPH on I-565. It would have dumped the mast out onto the highway, save the wire in the bottom loading coil was still attached. Nearly beat my roof to pieces before I could get stopped, tho!
The big problem was getting a replacement for the Loading Coil/Foldover Assembly. Repeated attempts at getting Gigaparts to order one for me failed; the store salesperson (apparently a neophite in retail sales) even told me to "get lost, don't come back"! Fortunately, Diamond dealt directly and courteously with me, and I was able to order Part No. 981101 from them directly ($50 plus shipping--www.diamondantenna.net). Pricey, but not nearly so as a new antenna.
Moral of the story: If you have an older HV7A, keep a sharp eye out for cracking around the insulating epoxy near the base of these antennas. Also would not be a bad idea to keep the hex key handy and occasionally give all the set screws a little torque!
Jim in Huntsville, AL |
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| W4VD |
Rating: |
2006-11-25 | |
| Great |
Time Owned: more than 12 months. |
Love this antenna, mine has been in service for over 3 years with an 8900R, many miles, hit many trees *installed on the luggage rack of a van* and she keeps on trucking, the fold over feature is very handy in low places, it's fairly narrow on 6m as some people mentioned, but being mostly on 1 freq on 6m, that is not an issue for me, 10 m works great, when it's open I work with the best of them. As far as 2 and 440, it's nice and flat, very well (pre)tuned, I don't see any noticable difference between this one and the dual bander it replaced as far as performance, I hear the "marginal" repeaters just as good if not better than with the dual bander.
Haven't tried any of the other HF resonators but if they work as well as the 6 and 10 meter bands it should be a nice, low profile all-in-one antenna package, |
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| N4LI |
Rating: |
2006-07-27 | |
| A Diamond, Somewhat in the Rough |
Time Owned: more than 12 months. |
I own a Yaesu FT-8900, so the choices of antenna are somewhat limited. The Diamond HV7A, or the Diamond 8900 (and the associated knock-offs) are really the only options without turning the car into a pin cushion.
I have owned 3 of these antennas, and have had mostly a positive experience. I recently had one fail – the resin insulator near the base sheared off, not unlike the previous poster. But, the antenna was fully 3 years old, and, frankly, had been bounced around quite a bit.* Let’s face it; this is a substantial antenna. There is a lot of strain at the base. This HV7A has ridden on my tailgate roughly 60,000 miles.
As far as performance, it’s about as good as one can expect from an admittedly compromised antenna. On 2m, SWR is fine (though it dips a bit high in the band). UHF is well within acceptable range. On 6m, like the other posters, the best I can muster is about 1.5:1 or 1.6:1 in a fairly narrow swath – not great, but acceptable. But, on The Magic Band, it seems to work about as well as a ¼ wave antenna is expected. When the band opens up, I easily make 6m FM sporadic-E contacts driving around town with the 50w output of the 8900. From Memphis, I have worked the Eastern Seaboard, TX, the Midwest, etc., with very little effort. Oh, and Florida… lots and lots of Florida.
On the 10m band, SWR seems a bit better – mine came in at ~1.2:1 in the FM section of the band, where I tuned it. It does not seem quite as potent on 10m as 6 (which makes sense, since it’s less than ¼ wave). But, I do make contacts on it (subject to the shortcomings on the radio on 10m). I hear 10m repeaters all Summer long. I hear W1OJ/r and KQ2H/r more than some of my local 2m machines.
If one wants an antenna they can set and forget while using a quad-band radio, this is the best choice. It’s just not a perfect choice.
Peter, N4LI
*And, it broke on one of the VERY rare occasions my wife drove my vehicle. I scored big points by not being mad when she called to apologize for breaking my antenna.
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| KC2JFS |
Rating: |
2006-04-04 | |
| Cubic Zirconia not Diamond |
Time Owned: more than 12 months. |
I have had two of these antennas. Why? Because two of them broke right in half !! The antenna was mounted on a Diamond Trunk Lip Mount. Both snapped where they pour the epoxy resin near the base. These antennas work well as a do all compromise; however because of Inherent Design Flaws I give them a revised ONE. They also loosen up frequently.
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Earlier 5-star review posted by KC2JFS on 2002-10-31
I have owned the Diamond HV7A and really must say it works great! My friend K2ESE helped me install and tune the antenna with his MFJ analyzer, there was a lot of trimming but in the end it was worth it. I own a 706MKIIG and the LDG RT11 tuner, all connected to my trusty Diamond HV7A. The coils I selected were the 10 & 20 meter ones. With this set-up I can effectively tune all bands 10-20 with a swr of 1.5 to 1 or less. I drive a company car and wanted the most unobtrusive set-up I could effectively operate. I use the Diamond K400 trunk mount and with one antenna and a push of the tune button get 70cm,2m,6m,10m,12m,15m,17m,20m. Now thats the cats meow! My signal reports have been great, with many a DX station saying that I sound better than a lot of base rigs. I would also like to add that I can operate 40m with a 2 to 1 swr in parts of the band. Overall a great set-up if you can't go all out, mounting a smokestack or chimney on your bumper.
73 all KC2JFS and THNX K2ESE |
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| KB1AWV |
Rating: |
2006-01-19 | |
| Fair to poor. |
Time Owned: more than 12 months. |
I bought mine used. It never tuned on 6 meters, not matter what I did. It tuned very nicely on all other bands (although bandwidth was a bit narrow) and I made many good QSO's. Unfortunately, it constantly came loose at the joints. The internal loading coil came loose. I returned the antenna and paid $60 for a fix. It worked for a while although it continued to loosen (set screws) at joints. Finally one of the plastic ferules that joins upper and lower sections split in half and the entire antenna was dumped on the road. Destroyed. Gone. Right in the middle of a QSO with a guy in Italy. Anybody want to buy a couple resonators cheap?
Be prepared to guy it if you use this antenna. My mount was a Comet that I had added 4 welded struts for additional stability. The mount never moved! |
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