| EI6DP |
Rating:  |
2019-01-09 | |
| Very Satidfied 10/10 |
Time Owned: more than 12 months. |
I have one of these antennas the T2FD not the T3FD. My T2FD came from a Canadian manufacturer.
Before making my purchase and like many other Hams I read the various items of information available and the many derogatory remarks and comments.
Having read between the lines so as to speak I went ahead and made my purchase :-) no regrets.
I was very eagre to put up my T2FD and to see how it was on receive. Using my FT817ND I found it a really great antenna and a virtually noiseless reception, there was some noisy spots :-) but no antenna is perfect. The noise was way down, about S2/3.
Here's the good bit :-) The T2FD is often referred to as a "dummy load" antenna and not good for DX (not that I am interested in DX) I went QRO with my FT817 and ran full power all of its 5W and believe it or not I made contacts on 7Mhz 14Mhz and 3.5Mhz later on that evening and receiving signal reports of 5/5 on 40m (Europe), 5/7>8 on 20m (US) and 5/6 into the UK on 80m.
I erected my T2FD as per instructions. I have it at 36' on an aluminium mast and down to around 15' to the garden fence. The centre support is a 2" fiberglass mast.
Am I happy with my T2FD = YES
Have I any regrets buying it = NO
If you are interested in buying or building one of these antennas I recommend that you read the many articles.
Read all the comments you can find.
Ignore comments like - I put it up and it didn't work.
I find my T2FD a really great antenna and to be honest I'm wondering why I didn't buy one 40+ years ago.
73's
Ger
EI6DP |
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| WB4ENE |
Rating: |
2018-04-20 | |
| Worth the Rx Noise Reduction and tuner goes on the shelf! |
Time Owned: more than 12 months. |
I've had the BBA-100C 27m/90ft 130W continuous antenna up and operational for 3 years in North Idaho. Its elevation profile is 30-15-15 ft, over my 2925 ft elevation catfish pond.
I entirely agree with G8JNJ's review below.
The power handling: So, how much can it really take? Bushcom's power rating is conservative. It took about 4 months to burn up at 800-1.2KW power on it, voice nets,CW, and digital traffic. The resistor load, which is a silicon-potted array of 8ea 10k Vishay non inductive resistors finally cracked. After DXEngineering/Bushcom refused to sell me a replacement because I had no bill of sale, I was on a mission... I replaced the impossible to repair without damage resistor box with 2ea in series 500 ohm 80's vintage Miluakee 25W resistors from eBay, hanging them in the middle wire, unprotected from the Idaho snow & rain. They lasted 8 months this time! Same nets, voice and digital. Note that the special Bushcom balun has not crapped out, and sweeping the VSWR curves has stayed consistent, using Array Solutions Aim 4170 and also their PowerAim 120 VNAs. (I hold 4 antenna patents)
On average, the Bushcom antenna's QRN noise floor was 2 s-units lower than 3 different OCF-D dipoles I built. I agree again with G8JNJ, that the theory is sound for this design. I agree so strongly that I then constructed dozens of my own NEC/4 models and constructed 204ft and a 266ft versions using DavisRF.com and wireman 12ga FlexWeave.
The Rcv performance of the 3 antenna lengths here is stellar! The Rx noise floor improvement is so good, that I could detect USB chargers, my farm elecric fence, noisy Genius battery chargers, the noisy Enphase solar inverters, and a wall wart in the cabin. I could not detect those noise sources with the off-center fed dipoles.
I think the radiation efficiency of the Robinson-Barnes design is BETTER than what my NEC models and Bushcom's models show. Why do the two 500 ohm eBay 25W resistors last so long? They don't explode or crack when the model says 975 watts in the load with 1500watts source, when my Alpha is fully lit up. My co-conspirator-patent-buddy Chad KK4NME wants to model it with HFSS. The possibility exists the lost energy is actually being radiated. This unproven guess is good news for you folks sitting on the fence because of detractors dissing "loss". You GAIN Receive floor signal to noise!
Did you know that Mr. Robinson owns Bushcom?
After reading Rudy Severns (N6LF) on conductor properties for lowband, and Montana hams wanting dipoles that will stay up in THEIR winters, I ran a set of models to find what gauge of stainless steel would approximate the performance of 12ga copper for 630meters. It came to 1/4" diameter SS. I'll stick with 1/8" SS because the 266ft weighs 75 pounds with copper, and may go to 90 pounds with marine grade stainless.
Bushcom, good on ya! Their T3FD design is complicated to build, and not designed to be fixed, but their product line is worth the complexity in this modern noise-polluted environment we live in..even on remote mountaintops.
The price. Now that I have built two, and I don't skimp anywhere in my prototype designs, and am working on a T3FD-73 73ft, and a marine-grade 266ft with 1/8" stainless cable, I can tell you Bushcom and DXEngineering are NOT gouging anyone at those prices. You are getting value, especially with the RX noise reduction. Have we forgotten the old saying about spend $9 on the antenna and $1 on the radio?? You just arent' an "amateur" when you decide to buy one. You are a communicator.
Radiation Patterns: the performance curves for the Bushcom are at 40m / 131 feet...WHO has towers that tall? Well, I have 130ft grand firs, but,they are thin at the top, and most folks are grateful to get their antennas up 30 feet. My T3FD-266 is 80-35-30 ft thanks to N7CMJ's tennis ball launcher. My models show what is more realistic to expect at the lower elevation profiles. The T3FD design and Bushcom's BBA-100 perform admirably at the lower heights. You just need to consider having a couple different length dipoles of whatever design you buy or build, so the NVIS gaps can be overcome. I have a graph of the various lengths and how important it is to have at least a PAIR of dipoles to overlap the NVIS gap at low antenna heights.
My Alpha is connected to the Bushcom, and my 2 other length T3FDs without a tuner.... ALE without a tuner, and hearing everyone all the time in the various nets is what you can expect.
Your mileage may vary, esp with the solid state amplifiers...but, ask Bushcom to increase the resistor load value to a higher number and you will make the amplifier happy. What is a few dB anyway, when propagation will go 100dB and more against you. Just QSY!
73'
ken
Cataldo Idaho
WB4ENE |
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| G8JNJ |
Rating: |
2017-05-15 | |
| Good design |
Time Owned: more than 12 months. |
I have spent several years testing and researching various forms of Broadband 'no tune' antennas.
The Bushcomm BBA-100 is a three wire version of a Terminated Folded Dipole, and is just about the best and most efficient type of this antenna that is available.
It does not use a 50 Ohm resistor at the feed point.
It uses a 450:50 ohm Balun to feed the outermost two wires which are connected at the far ends to the third centre wire which is folded back to meet in the middle where it is terminated with a 1200 Ohm resistor.
This forms a terminated transmission line radiator (a bit like a Beverage) which transforms it into a Travelling Wave Antenna.
The theory of this antenna is sound and only a significant amount of power is dissipated in the terminating load at frequencies where the overall length of the folded dipole is less than 1/2 wave long.
This antenna has been deployed and used by large numbers of commercial organisations worldwide.
It does trade some efficiency for a flat SWR across the whole frequency range, but not as much as some folks would have you believe.
Note that a standard ladderline fed Doublet when matched with a tuner, can easily have 2dB or more loss on some frequencies.
When compared directly with the Bushcomm BBA-100 there is not a great deal of difference in performance.
Unlike many antenna manufacturers who make outlandish claims about their products performance Bushcomm publish an accurate specification WRT achievable gain.
As with any antenna purchase, it's always worthwhile undertaking a bit of research before you buy. Then at least you will understand the theory and be able to make a sensible judgement WRT likely performance.
Regards,
Martin - G8JNJ
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| K6KV |
Rating: |
2017-05-14 | |
| Cheats... uses resistor for low SWR |
Time Owned: 0 to 3 months. |
| Antennas of this type claiming impossibly low SWRs across the entire HF spectrum are cheating, by using a 50 ohm load resistor at the feed point. Most of the power sent up the coax will be dissipated in the resistor, not radiated. That's why one of their antennas has a 60W rating... it probably uses a 50W resistor! These antennas will generate some contacts, of course, but nothing like that of an efficient antenna. Note that this type of antenna reappears from time to time and that QST magazine specifically prohibits their advertisements. I apologize for pulling back the veil however this company needs to tell the whole story about their products. |
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| VK3MNM |
Rating: |
2010-04-03 | |
| Great Antenna |
Time Owned: more than 12 months. |
What a great antenna!
This thing works fantastic, great reports from all over the world, couldn’t be more happy with it.
Its build quality is awesome.
I have a big problem here with Sulphur-crested Cockatoo's eating my antennas, the BBA-100 stoped them dead in their tracks, well done Bushcomm.
Had it up now for about 4 years and seen a few good storms and a huge hail stone attack that destroyed my pergola shredded trees and done million’s in damage to Melbourne.
It still works as good as the day i put it up.
If you are thinking of getting one you won’t be disappointed, just do it!
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| KR4K |
Rating: |
2007-03-04 | |
| Excellent Choice |
Time Owned: 3 to 6 months. |
Installed BBA-100E with OFO-Kit. Center is at 40 ft. with center hanging 5 ft. off tower and ends are at 30 ft. I use three towers to support. Ordered direct from Bushcomm.
Construction is outstanding, built like a tank. Installation was easy, but be sure and follow the installation instructions to prevent kinks.
I purchased for MARS, SHARES, SWL, and ham use. I use from 1.8 MHz to 30 MHz. VSWR does not cause TS-2000 to back down power without using internal tuner.
Have made 160m to 10m contacts, including recent 160m contest. Received reports as "strongest signal on band" recently on 17m with stations in MN, OH, and WA. MARS signal reports are that I came from weak but readable to often the strongest signal on the net, including 2.0 and 14.0 MHz frequencies.
I used B&W antennas for several years, and the BBA-100E is a dramatic improvement.
Only one wish - 4mm stainless steel wire instead of 2mm.
Highly recommend to anyone looking for one HF wire antenna. It just plain works. Bushcomm has an excellent product.
73/gus |
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| VK3MOA |
Rating: |
2006-03-30 | |
| Great Broadband antenna |
Time Owned: 6 to 12 months. |
I have used a BBA-100 for the last 9 months or so and I am impressed with how it works on such a wide range of frequencies.
I put it up against a standard wire dipole resonate for 40 and 80 meters, and although the reports back from others were not quite as good on 80 meters,on 40 they were similar. Logic and theory say that it won't be better than a resonate antenna, so I didn't expect it to be. But a resonate antenna on one band will not really work anywhere else. The BBA-100 will transmit anywhere from 2-30 MHz.
On receive it was quieter than my resonate dipole,but all signals could still be heard. There was less hash and background noise as well. And it could "hear" everything on all bands,all the shortwave stations and all the outback and 4WD frequencies as well.
The materials quality was excellent, too. All stainless steel with strong UV resistant balun boxes.
If you don't have room for more than one antenna, and want more than a couple of frequencies, I recommend the BBA-100 because it will transmit and receive anywhere from 2-30 MHz. |
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| VK6HTW |
Rating: |
2006-03-11 | |
| Product is very high quallity and virtually indestructable. |
Time Owned: more than 12 months. |
| These people [ BUSHCOMM ] are absolutely fantastic and easy to deal with their website is neat and infomative.My antenna the bba-100, at first seemed a bit expensive but the Quality of its construction will see it last for decades out in the harsh weather near the ocean. 5 years and still as good as new,stainless steel cable with fibreglass spreader rods, not aluminium/ PVC/ copper,etc. They are supplied all assembled and therefore very easy to install.Excellent for shortwave listening and covers 2-30 Mhz range (80-10m tx & rx) including all WARC bands plus military and marine HF frequencies. This unit is up to 2S points quieter on noise compared to the old 40m dipole, fantastic for my area. Signal reports worldwide have been excellent. So impressed with this antenna, I have bought a second product the SWCS Kit, again communication with these guys is terrific nothing is too hard very helpfull, premium service ++++. |
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| VK4DU |
Rating: |
2006-03-04 | |
| Robust, with good performance |
Time Owned: more than 12 months. |
BBA100 review
I run a comms engineering company, specialising in design and installation of HF point to point and land mobile networks, principally in the developing world.
As I’m sure you all know, the antenna is the centerpiece of any HF installation.
I needed an antenna system which:
covers a wide freq range (typically 3-12 MHz) with low VSWR;
does not need a automatic tuner;
performs well;
is very robust; and
is reliable.
Unfortunately, a lot of ‘broad band’ HF antennas offer wide frequency coverage with mediocre performance.
The Bushcomm BBA100 (3 wire) and SWC100 (single wire) antennas fulfill all my requirements.
They are robust antennas with good performance over a broad frequency range.
We have installed at least 500 of the BBA100 model and 1800 of the SWC100 model in some of the world’s harshest environments – the jungles of Papua New Guinea and the Solomon Islands.
Many of these installations were conducted by helicopter or outboard motor boat – the sites are so inaccessible, weeks of walking was the only other transport alternative.
In this situation, we simply can not afford to use an antenna which may fail – the logistic costs of replacing a faulty antenna run into the tens of thousands of dollars.
Of course, any broad band antenna is a compromise, however the Bushcomm antennas perform surprisingly well – at least on par with a dipole.
The BBA100 3 wire version also makes an excellent wide band receive antenna.
If you are looking for a good wide band antenna, and have a bit of space, I strongly recommend you consider the Bushcomm range.
Glenn VK4DU
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