| N6DC |
Rating:  |
2013-08-17 | |
| Excellent OCF Dipole |
Time Owned: more than 12 months. |
I purchased the 3 kW version of this Buckmaster 8-band (160, 80/75, 40, 20,17,12,10, 6m) OCF (off-center feed) dipole with the purpose in mind of having a single antenna to cover the lower HF bands (160/80/75/40m). I installed it on my tower in the recommended inverted-vee configuration with the apex (feedpoint) 64' up.
The unit appears to be well-designed and is well-constructed. Assuming that the balun transformer module is well-sealed, it should provide many years of trouble-free service.
Although I rate this antenna well, I do so with the caveat that it is a compromise antenna and that the prospective user must recognize the associated trade-offs and take them into account. Although it provides very wide frequency coverage without the need for an antenna tuner, it is most capable in the lower HF bands (160/80/75/40m). Although the unit maintains a reasonable VSWR on its higher bands (20/17/12/10/6m), gain pattern multi-lobing occurs which results in diminished performance in certain directions.
My rating is also based on the assumption that losses in the 6:1 feedpoint impedance matching transformer are low. The manufacturer does not publish a loss curve for this transformer and I did not attempt to measure it.
For my primary bands of interest (160/80/75m), this antenna performs well and I’m happy with it. On 40 meters, it is noticeably less sensitive than my Cushcraft D40 40m dipole (mounted atop the same tower at 80'). Of course, the D40's additional height gives it an advantage, but I suspect that the Buckmaster multi-lobing and other possible gain pattern issues may also be a factor. Although it is functional on 20/17/12/10/6m, I would use it only as a backup antenna on these bands due to these gain pattern issues. For these higher bands, I believe that a single-band or trap dipole at the same height would yield better performance.
Another issue I noticed was that despite the fact that my IC-9100 transceiver has an excellent receiver front-end with wide dynamic range, reception was degraded by a 13 kW 1550 kHz local AM broadcast station located three miles away. Without a doubt, this is caused by the fact that a full-size antenna for 160m is efficient throughout much of the AM broadcast band (as compared to an 80m or 40m dipole that would be far less sensitive to AM broadcast band signals). I was able to fix this by building an in-line highpass/notch filter to attenuate the offending AM station.
I believe that OCF dipoles work best on their fundamental and 2nd harmonic bands (i.e., 160 & 80/75 m for my unit). For the higher-order even harmonic bands, however, I believe a standard center-fed dipole would be a better choice. Even so, having the ability to operate on eight bands with a single dipole without an antenna tuner is an impressive capability.
For user’s considering this antenna, I recommend the model that covers no lower than the lowest band of interest. If 160m coverage is not necessary, it is best to obtain the 7-band version (covering 80/75, 40, 20, 17, 12, 10, and 6m). Similarly, if coverage is necessary down to only 40m, it is best to obtain the 4-band version (covering 40/20/10, and 6m). This approach minimizes the afore-mentioned multi-lobing and gain pattern distortion issues. As a case in point, I would expect noticeably better performance on 40 and 20m with the 4-band version as compared to the 8-band version. <> |
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| N0AZZ |
Rating: |
2013-05-26 | |
| One of the Best OCFD Antennas Made |
Time Owned: more than 12 months. |
I bought my first one in 2006 a 135' 300w one, had it hung poorly @26' as a flattop and 15' from the metal guttering around my house....But in 6 months I did work DXCC with it at 128 countries confirmed.
Since that time I have owned everyone of the antennas they make. I have sold all but 2 now that I now have and the ones I did sell I sold for not a lot less than I paid for them.
The 2 I still have are one a lightweight QRP model that I use among many others for portable use and the one I keep in the air all the time mostly for 160m and some 80m the 270' 3 kw 6-160m one mounted in an Inverted V @ 55' with the ends @ 25'. Both work very well for what they do. |
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| WB2JSY |
Rating: |
2013-03-30 | |
| INCREDIBLE!! |
Time Owned: 0 to 3 months. |
WOW!!
After being out of the hobby for 30 years, this is my first "TRY' of the4 hobby with a FT 950 100 watt Transceiver.
First Cq got me into Romania and subsequent CQ's all over Europe and The US.
The antenna is incredible, however, I am NOT!!
Lots of TVI thru my Directv TV and computer and neighbors!
I need help!
The antenna is great but I need assistance with the TVI.
Where do I start?
Incredible antenna... nothing better... at 40 feet and about a 120 degree angle, luckily as mandated, but my wife is getting used to it.
How do I get rid of the TVI with Directv TV and issues with my computer.
The antenna is incredible; I am not!
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| K9DY |
Rating: |
2013-02-24 | |
| Great results |
Time Owned: 3 to 6 months. |
This antenna surpassed my expectations. The SWR is very good on all advertised bands, and 30 and 160 work well with a tuner. I was skeptical but it performs very well. I worked 9U4U on 17 meters on the first call on SSB with 100 watts. I also have a GAP challenger vertical which also works very well, and most times the antennas are comparable, but the dipole usually has a slight advantage on 40 and 80 meters.
I am in a restricted community, so the antenna is located in a heavily wooded area behind my house. It is 40+ feet up in a tree and the ends are as specified at about 45 degrees in an inverted vee. It is fed with about 150 feet of 9913 coax. I have the ends fitted with pulleys and weights to counter the swaying of the trees. This antenna is very robust, so I have little fear of it breaking.
Days after ordering the 300 watt version I had thoughts about buying an amplifier in the future. I returned the dipole unopened and ordered the 3 KW version. No hassle with the return to Buckmaster.
I feel I made a good choice.
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| AK4QR |
Rating: |
2012-10-10 | |
| Love it! |
Time Owned: 6 to 12 months. |
Great performer! I do not use a tuner. I've had it installed at 23ft and now at 35ft. With SWR very low on all band except 15 is close to 2. I've talked all over the world with it. Using up to 1kw when needed. Only small issue is it's a little noisier than my Mosley 33 but I think that's just the nature of wire antennas. Or could be that it's minted on a mast attached to the house and the beam is 250ft away from everything
Being a new ham I have nothing to compare it to being better than other wire antennas but it does what I expect with no tuner!
73's |
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| W7CSD |
Rating: |
2012-04-16 | |
| Fills the bill, couldn't ask for anything more... |
Time Owned: 0 to 3 months. |
I wanted a wire antenna for my station that would cover most of the HF bands without much tuning. I decided upon the Buckmaster OCF antenna for a couple of reason: First, I didn't like the shedding skin on the Alpha Delta antennas and I wanted something that didn't stand out in the yard. The Buckmaster did both. I am impressed with the construction and also with the performance so far.
Something I struggled with; how do I construct a nonmetallic standoff to keep the auto-transformer away from the tower? My solution was to get a fiberglass axe handle from the local home improvement store, paint it to something that didn't stand out and use a couple of "U" bolts to secure it to the tower. It's strong enough, works good and didn't cost much.
If I had to go out today and buy another antenna, I would definitely buy another Buckmaster OCF 7-Band antenna. |
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| W6FG |
Rating: |
2011-12-20 | |
| Works for a while... |
Time Owned: more than 12 months. |
I've used the KW model for a couple years now and at first I really liked it. But when the vswr went sky high on a couple of bands, I contacted Buckmaster. They told me to send mine back and they would give me a discount on a new one. Well, even with the discount it wasn't all that cheap! So I put the second one up. Now lately, I can't apply more than about 10 watts on 40M before my K3/Astron 35M shuts down; similar to my first experience with this wire.
It does seem to be well made. I guess because I used it on 30M and it's not advertised to work on that band, it's my fault that the balun burned out. I thought that something that looks that heavy duty could stand 100W CW on a non-resonant band. So, I'll not be buying #3 form Buckmaster! I'll be looking for another 'all band' type of wire to throw up. Maybe a G5RV or one of the other makes of OCF wires. If you use it ONLY on the bands it is cut for you might be OK, but I've given it two chances and that's enough for me.
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Earlier 5-star review posted by W6FG on 2007-02-17
I had an off center fed dipole fed with 450 ohm ladder line and it did OK. The ladder line ran across the tin rain gutters and I didn't like that. So, up goes the 3KW OCF from Buckmaster. I got it up in time for the ARRL CW DX test. Wow! I'm hearing things and working them too! This antenna is going to be a big help for my 40M totals! Eighty is also alive as well! It's not squirrely when I feed it some pwr either, I like that! Very heavy duty and well made. This thing is going to last. In my installation I need a tuner for 30, 20, 17, and 15 meters, I can bypass the tuner on the other bands eg. 80, 40, 12, 10 meters. It's a little long so the long leg bends at a tree branch about 3 feet from the end. It's erected as an inverted V with the apex at about 30 feet. I also like how the wire used is easy to work with, it doesn't keep kinking up like the other one did. It was hard to shell out the dough for a wire antenna but now I'm glad I did. Maybe another update after I've had a while to operate with this one. I think this and putting up my Butternut should give me a very workable station. |
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| KN2M |
Rating: |
2011-11-28 | |
| A lamebrane packaged this antenna |
Time Owned: 0 to 3 months. |
| "Needs help" is a great description. I am pretty organized person and have been putting up antennas for 50 years now. I scouted out my property in August for installation. I had pull ropes up already in the selected tree. Everything was ready to go except the weather. It is now November, cold and wet. At least the leaves are off the trees and I can use my Chief AJ slingshot to put up the ends. I laid the antenna under the pull rope, attached the RG8X and quickly uncoiled the short end to measure the distance to my anchor point. All OK. I knew the long end did not need a measurement to the anchor so I started to pull the antenna up. Much to my horror, I noticed the long end was wound with a locking turn of wire just off the center insulator and it was impossible to uncoil it like the short end. The whole antenna had to be pulled through the locking loop of wire. There was no other way. This took me at least 20 minutes in the cold and rain. I was really frustrated due to the lack of attention to detail in the manufacture of this product. Once up, I noted that I was able to work some DX barefoot. My first QSO was a VP2M from New York on 80m CW. Not bad. In comparison to my other antenna, a SteppIR vertical, most stations are louder and stronger (40m) on the vertical which is about 30 feet away. Haven't used it on the higher bands too much for comparison. I listened to stations on 80 CW and the OCF is about 3 or 4 S-units stronger, which makes sense because the vertical does not have the 80m coil. The center of the OCF is about as high as the SteppIR is tall and the ends are about 10' just as the yellow diagram paper suggests. The VSWR matching seems to be fine on the bands too. So, no complaints about the performance. |
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| K4RMH |
Rating: |
2011-11-13 | |
| Solid Performer! |
Time Owned: more than 12 months. |
| I have this antenna mounted approximately 30 feet in the air in an inverted vee as suggested. SWR accrosss the bands is pretty much like advertised. DX calls made into Eurpoe, SA, etc. are clear and contact on the first call is almost guaranteed using only 100 watts..! |
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| KK5GG |
Rating: |
2011-09-25 | |
| Works Great Heavy Duty |
Time Owned: 3 to 6 months. |
| Works great and heavy duty. Great for higher wind locations when mounted in trees. I feed that baby w/250 ft of Terrawave 600DB coax and it handles 1500 PEP with no problem. It is 135' so it takes a little real estate to install it properly. |
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