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Reviews Categories | Antennas: HF: Vertical, Wire, Loop | DX Engineering DXE-8040VA-1 80/40 Meter THUNDERBOLT Vertical Ant Help


Reviews Summary for DX Engineering DXE-8040VA-1 80/40 Meter THUNDERBOLT Vertical Ant
DX Engineering DXE-8040VA-1 80/40 Meter THUNDERBOLT Vertical Ant Reviews: 11 Average rating: 5.0/5 MSRP: $799.00 INTRODUCTORY!
Description: A high-performance vertical antenna specifically for the 75/80 meter and 40 meter bands! The DX Engineering 55-foot Dual Band Vertical Antenna supplies performance which is virtually indistinguishable from their mono-band vertical antennas—perfect for areas where there is no room for individual verticals plus uses the same radial system for both bands. Achieve the strongest possible presence at your power level and be competitive!

Covers the whole 40 meter band with one setting!

80/75 meter band is tunable down to 3650 kHz center frequency with 300 kHz bandwidth. This means that operation on the CW DX frequencies and DX Phone frequencies is within range of most radio internal tuners - no antenna changes are necessary to switch frequencies!

Optional CW Optimizer DXE-7580-THK Capacity Hat Kit allows adjustment down to 3400 kHz center frequency for dedicated CW ops and military/MARS ops.
Product is in production.
More info: http://www.dxengineering.com/parts/dxe-8040va-1
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You can write your own review of the DX Engineering DXE-8040VA-1 80/40 Meter THUNDERBOLT Vertical Ant.

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VA3DM Rating: 5/5 Jan 11, 2016 14:32 Send this review to a friend
Worth every penny and you don't even need to guy it!!!!  Time owned: more than 12 months
I just wanted to follow up on the review I submitted about three years ago. This antenna is an absolutely superb performer and built like a battleship.

I have been using my "Thunderbolt" on a daily basis for about 3 and a half years and it has performed flawlessly except for one thing!

Please note that because the antenna is located in a HIGH WIND ENVIRONMENT on top of a hill and I CHOSE NOT TO GUY THE ANTENNA, a trap restoration was needed as the 40m bandstop filter had become detached from the antenna during a windstorm and fell to the ground. Electrically, this left the 40m part of the antenna, leaving the upper part of the antenna electrically disconnected due to the insulator between the two sections. The trap was attached with factory parts composed of three custom compression clamps with threaded studs welded into them. These studs are used to connect the trap to the clamps. All three of the clamps failed at the stud weld point.

While I cannot know with certainty the reason for the failure, the location of the antenna is such that it is frequently subject to strong winds. Since the antenna is not guyed, much of the strain of the flexing of the antenna is borne by the traps which bridge the two antenna sections (separated by a stiff fiberglass insulating insert).

I believe that the failure occurred due to metal fatigue - most likely due to the frequent flexing of the antenna in the wind. While mitigation against flexing could be taken by guying the antenna above the trap, such guying would work against the desire to be able to lower the antenna periodically to avoid damage during major storm events.

The Solution

Replacement of the original clamps with new units was not favored, as in this environment there is a high probability that new parts will eventually fail in the same way. Various approaches were evaluated to re-attach the trap while at the same time strengthening it. The method chosen was to create a formed metal strap that attaches tightly in the middle to the trap where the original stud would have been. Two compression clamps (unmodified) were then used, one on each side of the metal strap to hold the strap securely to the antenna where the original clamps had been. This approach is simple to implement, inexpensive, removes the inherent weakness associated with the welded studs on the original clamps, and should more than double the strength of the attachment. All parts used were stainless steel or zinc plated to minimize rusting over time.

The trap was re-installed with the new hardware. During assembly, a fourth compression clamp failed (on the trap side), and was similarly replaced. There remains one of the original compression clamps, which had not failed to date (it's now been 1.5 years since applying the mod) and may well not fail given the new strengthening of the system.

Electrical testing of the antenna showed that dual band 80/40 behavior had been restored. Testing was done with a Rig Expert AA-54 antenna analyzer.

In conclusion, DX Engineering certainly CANNOT be faulted for the failure of the original clamps because I chose NOT to guy the antenna AGAINST THE RECOMMENDATIONS OF DXE even though the antenna is installed in an environment where the wind gusts exceed 75 mph!! With the way I installed the antenna base (using a rebar cage and high strength concrete like they do with tall light standards along major highways), the antenna has remained upright for the last 3.5 years without the need to lower it!! Sure, it sways a little in high winds, but that's all! If anyone reading this wants further info, you may wish to see my posting on (with photos) on QRZ.COM.

TIME HAS NOW PROVEN TO ME THAT THE DXE-8040VA-1 DOES NOT NEED TO BE GUYED PROVIDED THAT IT IS INSTALLED AS DESCRIBED ABOVE.

Would I buy this antenna again?? Yes, in a HEARTBEAT!!

Congratulations DXE on a robust product which has withstood the test of time. If DXE wishes to introduce a minor mechanical design mod to the 40M bandstop filter (trap) assembly, I believe this change could be made at minimal additional cost (but, then again, antenna was never designed to be erected without guying!
 
N4UP Rating: 5/5 Sep 8, 2015 12:57 Send this review to a friend
Even better than expected  Time owned: 6 to 12 months
First let me express my bias right up front. This is a magnificent antenna.

1. Engineering/Design and Quality of Materials. Excellent.

This is a first-class design. The base section is 3” in diameter and the top section is 1” in diameter. It is free-standing and 54’ high assembled without adjustment, but I chose to three-way guy the antenna as an additional precaution in high winds, to protect the optional CW capacity hat from neighboring tree branches. The capacity hat sits above the guy point so the guy ropes do not interfere with anything. If you use guys, you have to be careful adjusting the guy ropes. You don’t want to pull the antenna over ( I did that once with a hex beam; it was not pretty ).

2. Base, Coax, and Radials.

This antenna requires a substantial foundation/base. I dug a hole four feet deep and about two feet on each side, with some gravel at the bottom, placed the recommended customer-supplied Schedule 80 support pipe in the hole, and had redi-mix concrete delivered. Once the concrete was set, I applied Rustoleum primer and black paint to the support pipe.

For coax I used 175 feet of DXE400MAXDX, from the antenna base to just outside my radio room, to a DXE remote coax switch and polyphasor lightning protector. Buried 12” deep through the front yard but 6” deep through the woods, to minimize interfering with roots.

I placed 64 radials in the woods, each 65 feet long. In my case all I had to do was use a garden hoe to “cut” through the dirt under the pine straw, lay the radials with staples every few feet, and then cover with pine straw.

3. Assembly and Documentation. Excellent. Documention is detailed and straight-forward, with excellent diagrams and pictures. Much better than the documentation for any of the other antennas I have built over the years. Assembly goes smoothly, except for a few typos and a some wrongly-sized bolts.

If you take your time, read the instructions for each step, and proceed when you understand what to do, it is easy. The typos are not fatal. Easy enough to figure out what they should have said. Likewise the bolts. They supplied two hex bolts for the VA-1 that were too short and one bolt on the 30 meter accessory that was also too short. Solution, go to the hardware store, buy longer bolts, and flirt with the girl at the register. No problem.

The entire assembly and raising is a one-man job ( assuming you have the winch accessory ). Crank the winch slowly and keep an eye on the antenna as it is being raised. This is especially important if you have the CW capacity hat installed. Watch out for the bouncey. This antenna is very long and flexible. It will go bouncey on you when you are raising or lowering, so go slowly and gently.

Without the CW capacity hat, I placed my sawhorses flat on the ground for support. With the CW capacity hat installed, I placed the sawhorses upright, to be sure the capacity hat doesn’t touch the ground. The “bouncey” will get the capacity hat if you are not careful.

Helpful hint. I did most of the assembly in my ( large ) garage and then moved things out in sections to the antenna base. I carried the actual antenna in two trips, as it is 54’ long and I wouldn’t have been able to maneuver that through the trees. I had no trouble attaching the two pieces “in the field” and attaching the “antenna” to the base.

Helpful hint. In my case the location was in the woods, with trees 10-12 feet apart. I had to trim tree limbs around the base location AND above where the antenna sits before being raised. The CW capacity hat, six feet in diameter, adds to the space required.

Pay attention to the location of the feedpoint coil and optional 30 meter support. They need to be on opposite sides of the antenna and placed in such a way that you can raise or lower the antenna without breaking anything. Make it like the pictures in the documentation and you shouldn’t have any problems.

4. Accessories. Excellent. I purchased all of the recommended/available DXE accessories --- the radial plate, radial wires and hardware, removable manual winch, CW capacity hat, and 30 meter element. I also used the recommended anti-seize and penetrox. I hate that stuff, very messy, but it is a necessary evil. Whenever you raise or lower the antenna, you’ll need to take out/re-install four bolts, which is easy enough if you have used the anti-seize. The feedpoint coil and the 30 meter element both need to be attached to the radial plate and THAT hardware is not included with the VA-1 so use the hardware that comes with the radial plate.

5. Performance. Excellent. I didn’t do any of the “tuning” exercises. I just assembled and installed the antenna, checked the resonant frequencies and SWR as a sanity check, and started using the antenna without a tuner. It seems to work very well on both 80 and 40 meters. With the CW capacity hat “on” … I do need a tuner only for the higher SSB portion of 80 meters. On 30 meters I prefer my 10-element LPDA at 73’ and have the 30 meter element on the VA-1 to use only as a backup antenna.

On 80 and 40 meters I can only compare the VA-1 performance to my 270’ long 160 meter OCFD at 40 feet, which works reasonably well on both bands. On TX the VA-1 is much, much better than the OCFD and gets even better with distance, as you might expect. On RX, I hear better on the VA-1 than the OCFD, which is a bit surprising. The VA-1 is not noisy! I still plan to build some receiving antennas for 80 and 40, but the VA-1 hears better than I expected.

6. Price. This is not a cheap or cheaply made antenna. You pay for quality and performance. In this case a first class antenna.

Would I buy one again? Yes, definitely. Though I expect this one to last.
 
HS0ZIB Rating: 5/5 Apr 30, 2015 23:17 Send this review to a friend
Cannot fault it - worth the money  Time owned: 3 to 6 months
I purchased the Thunderbolt 8040VA-1 antenna, with 80 metre band capacity top hat, (because the 80 metre band allocation in Thailand is only 3.5 - 3.54 MHz). I also purchased the add-on, 30 metre band kit and radial plate.

Importing this antenna into Thailand was a major headache, with the Thai customs demanding an import licence and almost 100% of the value as customs duty. Being used to their corruption, I refused to pay the inflated amount of tax, and after a 1-week 'stand-off', the antenna was available for collection from the local customs office for an extra tax of about 20%.

The build quality, as with all products that I've purchased from DX Engineering, was second to none. Installation details were very clear and I had no problems to put everything together, with one small exception. When installing the add-on, 30-metre band kit, be careful that the screw body of the jubillee clamps used to secure the wire stand-off at the lower end of the wire do not foul the securing bolts of the main 80/40 tubing. I didn't notice that the screw body was shorting to the main tube and wondered why I could find no resonances! To correct this problem, loosen the clamps and adjust them so that the clamp body doesn't short - I moved the clamp body to allow a 2mm gap.

I purchased my antenna without the winch (shipping costs were too high to Thailand), so I had to manually riase the completed antenna. Unlike a 43 feet vertical antenna, this 80/40 monster definitely needs 3 people to safely raise it into the vertical position. I tied a support rope halfway up the antenna and passed the rope over a nearby tree to assist in raising the antenna.

The antenna stands 55 feet high in the middle of my garden, without any guy wires. In strong winds, the antenna sways gently, unlike more flimsy, 43 feet antennas, which often sway violently (but still safely).

I installed the radial plate and ground radials. Due to my garden size, it was not possible to install radial lengths that are recommended for 80 metres, so I had to compromise.

Using my MFJ antenna analyser, I followed the printed tuning procedure. SWR between 3.5 - 3.54MHz, 7.0 - 7.2MHz and 10.1 - 10.15MHz was no higher than 1.2.

So what about performance 'on the air'? Here are my results after a few months of use on the bands for which the antenna is designed for (80, 40 and 30 with the add-on kit)

30 metre band - Using digital modes and the reverse beacon network, I have daily QSOs out to about 10,000 miles (Europe, Russia, Asia and Australia from my QTH in Thailand). My signal is also heard on both west and east coasts of the USA, but I'm not hearing the signals from those hams. This makes sense, because vertical antennas tend to be more noisy on receive than horizontal antennas. I am going to install a 30 mb dipole for receive mode.

40 metre band - Testing as per the 30 metre band, but also with SSB, I achieve the same coverage on transmit and the same issues on receive. The lack of reception on receive is compounded by local QRM from Indonesian/Malaysian SSB stations (very loud at my QTH). Because of this local QRM, I currently don't plan to install a 40 metre band receive antenna, unless I use one with a good F/B ratio to null out the local signals.

80 metre band - As mentioned in this review, my radials are really not long enough to provide an efficient ground on 80 metres, and so far, no QSOs have been achieved. But my signal is being heard in Europe and Australia. My lack of QSOs is also because Thailand only authorises 3.5 - 3.54MHz, so 'standard' JT65 and SSB frequencies do not fall within that narrow band.

For 80 metres, my plans are to try to improve my radial field and to install a receive antenna. But more importantly, I really need to wait until the 80 metre band allocation is expanded, to allow me to operate on 'common' frequencies.

Summary of the antenna for these bands: Excellent performance. Any issues are due to my own installation or operational limitations.

It is also worth mentioning how the antenna performs on other amateur bands. Note that I do not use any antenna tuner (internal or external to my rig).

20 metre band - SWR across the band is no higher than 1.2. I have been able to have many QSOs on this band.

17 metre band - High SWR. The antenna cannot be used without a tuner

15 metre band - SWR no higher than 1.2 across the band (21MHz is 3 x 7MHz). Many QSOs

12 metre band - SWR is 1.0 across the band, many QSOs

10 metre band - High SWR, need a tuner.

So even without any tuner, this antenna can be used on the 20, 15 and 12 metre bands.

It is also worth noting that the antenna could also be used on 160 metres, if an 80 metre band trap is installed at the top of the antenna, and then a horizontal wire run to create an inverted L antenna. The top-most aluminium tube is rigid enough to support a trap (I have already obtained a custom trap from Unadilla, and will be adding it and the horizontal wire to my antenna in the next few months). I'll report back on 160 metre band operation after I make this modification.

In conclusion, I highly recommend this antenna for low band DXing, as well as higher band QSOs. Low band operation may require a separate receive antenna, (as with any low band vertical), to minimise the noise level. Operation on several of the higher HF bands is quite possible without any tuner, because the SWR is low.
 
N3HSH Rating: 5/5 Sep 24, 2014 15:10 Send this review to a friend
Solid Construction, Solid Performance  Time owned: 3 to 6 months
Other reviews have commented about the sturdy, quality construction and have called this antenna a "battleship." I would have to agree. My primary enjoyment on the lower bands is working DX and after looking at many antennas, I decided the simplicity of design and heavy-duty construction of this would serve my needs for a long time.

This antenna replaced a Butternut HF2V I had for years. The Butternut is quite a compromise on 80 meters with a narrow bandwidth and is only 1/8th wave for that band, although it did perform very well for me on 40m.

I dug a 4' deep 2' square hole, purchased a seven foot long, 2.75 inch diameter, 1/4 inch walled steel pipe from one of the vendors suggested in the DX Engineering instructions for the mounting post, a DX Engineering radial plate and rolls of bare copper wire for radials. I also purchased the optional winch assembly used to raise and lower the antenna which makes tuning or simply lowering the antenna if desired in the event of severe storms a snap.

Assembly of the antenna is straight forward. The antenna tapers from a 3 inch diameter at the base to 1 inch at the top. It is self-supporting up to winds of 55mph. I have experienced winds of around 40-50 mph at my QTH and the antenna swayed a bit but had no problems.

I came up short on a few small parts such as washers and nuts but these were easily sourced at the local big box store.

Using the radial length calculation information found in K3LC's article "Maximum Gain Radial Ground Systems for Vertical Antennas" from the 2004 ARRL Radial Contest Journal as a guide, I ended up with
about 5,600 total feet of wire among 59 total radials. These are made up of 39 radials 110 feet long and 20 radials at 65 feet long.

SWR on 40 meters is 1.8 at 7 Mhz and 1.5 at 7.3 Mhz. The 2.0 SWR spread on 80 meters goes from 3.650 Mhz to 3.92 Mhz which is very close to the manufacturer’s claims.

I also added the 30 meter kit which covers that band end to end with an SWR of 1:1.

This antenna works great for DX even when running barefoot. When conditions warrant, I use an amp with about 400 watts and the DX always comes back to me on the first call, even in pileups. Being a vertical with an extensive ground system, this antenna is not well suited for local, stateside contacts, but that is not what I wanted it for.

At 55 feet tall compared to the Butternut's 33 feet, it clearly outperforms my previous antenna on 80 meters. I expect it to serve me well for a long time to come.

73
N3HSH
Charlie
 
DL1QQ Rating: 5/5 Sep 23, 2013 10:37 Send this review to a friend
Good choice!  Time owned: 0 to 3 months
We are a group of 10 hams setting up a joint location in Ottenstein. That’s a small village on a mountain plateau in the northern part of Germany. For the high bands we use monoband yagis. For the low bands we only had dipoles so far. Our newest purchase now is a vertical for 80 and 40m. We picked the 8040VA-1 Thunderbolt from DX Engineering. No problems with shipping from the USA to Germany. And the antenna was very easy to install. Even though we don’t have very much space at our location (there is no possibility to spread out 40m long radials in all directions), the performance of the antenna is great. During WAE SSB Contest on second weekend in September I got to use the antenna for the first time. In spite of poor conditions I got to work DX stations on 80 and 40.
I am looking forward to more operations with this antenna.
73/88 Sandy


 
VA3DM Rating: 5/5 Dec 3, 2012 14:29 Send this review to a friend
A well designed antenna that provdes exceptional DX performance  Time owned: 0 to 3 months
I purchased the 8040A-1 Thunderbolt toward the end of September 2012 and I am extremely pleased with it in all respects. The design of this antenna is thought out in terms of both mechanical and RF design and the supporting winch is heavy duty in construction using top quality parts. It provides for easy raising and lowering of the antenna with only one person. Due to its robust construction, I call the DXE 8040VA-1 my “battleship” antenna! The antenna is clearly made to last and has already proven to be able to handle gale force winds. And I have no doubt that it will be able to handle severe icing conditions too.
The assembly of this antenna was very straightforward thanks to step-by-step instructions plus clear close-up photos and illustrations. In addition to the excellent written instructions provided by DXE, I also followed K0CN’s great 5 part series of You Tube videos which details the entire assembly and testing process from start to finish. A clearly written assembly manual coupled with the K0CN’s videos made it a real pleasure to put this antenna together! Thank you both DXE and Al – K0CN!
The only issue I had when assembling the antenna was that one of the SS studded element clamps provided for mounting the trap was the wrong size. However, this matter was quickly resolved through an e-mail with George – K3GP who immediately sent me the missing part without hesitation! Being a mainly CW operator, I ordered the optional capacity top hat which went together easily and did was it was designed to do.
I live on top of a hill with frequent gusty winds (and a great view). I also didn’t want to use guying with this antenna so I designed a super-strong foundation for the 8040VA-1 using a large 30” diameter sonotube with an internal multi-level rebar cage to be filled with 32 MPa concrete. The mounting post that I chose to use is a 3.0 O.D. Schedule 80 tube for extra strength. I installed at total of 80 -64 ft ground radials plus two 10 ft. ground rods for lightning protection. Some photos of my installation have been included in my qrz.com listing.
The tuning of this antenna was fairly straightforward and took about an hour and a half to complete. The antenna provides me with an SWR of 1.2:1 across the CW portion of the 40M band and between 1.3 and 1.5 to 1 on the CW portion of the 80M band.
Performance to date has been outstanding! Within just a few weeks of operation, I easily worked Peter - ZS1JX near Capetown, South Africa on 80M using only 15 watts output from my Ten Tec Argonaut V! This was followed by a great contact with Brian - ZL3XDJ near Dunedin, New Zealand on 40M (he was using only 10W into a ground loop)! More recently, I was able to crack pileups on both 40 and 80 for the PT0S DXpedition (again, feeding only 15 watts into my new DXE vertical)! Finally, I worked 7J1YAJ near Tokyo on 40M during the recent CQWW CW Contest amidst M-class solar flares that had been plaguing the ionosphere at the time!
Thank you DX Engineering for a well designed and very robust “killer” DX antenna that is sure to give me a great deal of DXing pleasure for many years to come!
 
K1TKL Rating: 5/5 Oct 18, 2012 13:42 Send this review to a friend
Excellent Product  Time owned: 0 to 3 months
I purchased this with the addition of the 30 meter option, winch, and capacity top hat.

Well thought out mechanical/RF design. The small parts were sealed in clear plastic strips, allowing easy assembly without misplacing/losing small parts/hardware.

The instructions with the kit are excellent. The use of photos enhances the ease of assembly.

Support from DX Engineering is excellent. I had a minor problem tuning during initial startup.

The winch, gives the ease of lowering this massive antenna for tuning and (future) maintenance.

The only two negatives I experienced were: (1) Two of the SS clamps provided for mounting the trap were the incorrect diameter (too small). (2) The L-bracket on the base coil had the mounting hole too small to mount to the bolts provided with the DX Engineering radial plate. (I had SS clamps and the hole was easily drilled to the correct size.)

The installation is with a 9' foot ground rod at the base of the antenna (salted with copper sulfate solution), and over 100 radials installed with some exceeding a length of 300 feet.

Performance is excellent. The antenna does load on the higher bands. On 12 meters barefoot I worked Europe from S. Calif. with 57 to 59 reports.

On 75 and 40 it is a killer with the amp. I have yet to move down to the 80 meter CW portion.
 
K0ZR Rating: 5/5 Sep 22, 2012 09:13 Send this review to a friend
You Won't be Disappointed With the Construction or Performance  Time owned: 0 to 3 months
After you "write the check" expect to be impressed with the overall construction of this antenna. This is a Cadillac in my estimation, and needs to be in order to be free standing.

I use 75 radials at the base, each a quarter wavelength long. For short distance QSOs my inverted vee at ~ 70 ft typically outperforms the vertical, sometimes by as much as 20 dB. However, on the long hauls where one needs low angle radiation, this antenna shines. I am working pacific stations, even in moderate pileups, on the first and second calls.
 
K0CN Rating: 5/5 Oct 3, 2011 22:25 Send this review to a friend
High quality antenna with a great support staff.  Time owned: 0 to 3 months
I purchased the Thunderbolt in August and made my first contact at the end of September. The construction was involved, but a good experience with the quality of materials, hardware, instructions and support making the process a very good experience. All the pieces fit together precisely and were arranged in the shipment to minimize confusion. Making the base assembly required digging a hole, mixing about a yard of concrete and finding a 7' by 2 1/2" schedule 80 pipe to set in the concrete. All were very doable tasks. Assembling the hardware was enjoyable because it is a pleasure to work with quality materials and the process was well documented in the manuals. When there were questions, the support staff at DXE was just a phone call away and very pleasant to work with.

I documented the construction of the antenna in detail. You can view the process on YouTube at:
http://www.youtube.com/watch?v=6lsx_h8dh7I
This is the first of a 5 part series. If you have the time to watch, I hope you find them helpful.

I located the antenna about 100 feet away from my house and was able to put out 60 radials that were 65' in length (3900' of #14 THNN wire). I had a couple of obstructions that required me to shorten about five of the radials to 50 feet, but I don't think I will notice that. I buried my feed line using DXE direct burial 50 ohm coax. I only trenched the feed line about 3 inches deep, so I also choose to use a current choke at the antenna to prevent possible induced current problems. The antenna assembled and tuned very smoothly and with the optional manual winch, raising and lowering the antenna for tuning was a snap. After tuning I constructed a plot of the swr for all three bands. In all cases, I was able to measure less than 2:1 on 80M over a 300kHz spread, nearly 1:1 across the 40M band and 1:1 across the 30M band. I am very pleased with the installation and the quality of the antenna.

My on the air experience has been brief and as it is still summer, I feel the best is still yet to come. My first night on the air found the bands to be in good shape. I first worked France and then Bulgaria on 40 CW, both with 2x 599 signals. I then switched to 80 and heard an RTTY contest going on and worked an Italian station with a 599 report. About a week later I was able to get on the air and try out the 30M add on kit. My first contact was Nicaragua and then East Kiribati (Christmas Island). I worked them both with a single call. A short time later I worked Kiribati again on 80M with about a 579 signal. Not bad in my book. The antenna is an impressive addition to my station and I am looking forward to many more good experiences.
73 - Al K0CN
 
K6AAX Rating: 5/5 Apr 16, 2010 14:56 Send this review to a friend
Very Favorable  Time owned: 3 to 6 months
I purchased this Thunderbolt back in the fall, and I have had a chance to make some long range TRANSMIT ONLY comparisons between this antenna, the Cushcraft MA 80/40 vertical and the RadioWavz 246ft 160/80/40 OCF dipole from my QTH. It surely could vary at your location. My comparisons were on 80 and 40 meters only. I have over 40 1/8th and 1/4 wave radials under both the Thunderbolt and the Cushcraft MA 80/40V, plus chicken wire on top of the radials. The OCF dipole is at 50ft. I use a K9AY loop for receive on these bands.

Within 1,000 miles on 80 meters...the Thunderbolt edges out the OCF dipole 95% of the time and crushes the Cushcraft 100% of the time. Over 1,000 miles the Thunderbolt consistently beats the Cushcraft MA 80/40 V by 1 to 2 S units and the OCF dipole by 2 to 2.5 S units. These tests were done on 80 meters 6 times. 2 tests were with the UK from California on phone at their sunrise this past winter, and 4 tests were done with South Africa on 80 meter phone from CA at their sunrise. The Thunderbolt received the best report 100% of the time-6/6. The Cushcraft was better 83.3% of the time over the OCF dipole-5/6 (except for one time with the UK). It should be noted that I was heard all six times on all 3 antennas...with legal limit on 80 meters, which really is all that matters, right? :-)

On 40 Meters, the Thunderbolt is about 1 to 1.5 S units louder than the Cushcraft MA 80/40 V over 1,000 miles. The Cushcraft does perform much better on 40 meters than on 80 meters, however. It closes the gap somewhat but not all the way. I did 6 TRANSMIT ONLY tests, 2 with JA, 2 with ZL and 2 with South Africa. The Thunderbolt again performed best 100% of the time-6/6. The Cushcraft also performed better than the OCF dipole 100% of the time by a .5 to 1.5 S unit difference. There was 1 time where the South African station could not hear me on the OCF dipole with legal limit on 40 meters. In all fairness, the conditions were rough. I could be heard on the Thunderbolt and Cushcraft all 6 times, however.

This may not be scientific, but these are the facts. I now use my OCF dipole as a supplement receive antenna to the K9AY...hi hi.

This just may be one of the best verticals on the market.
 
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