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| Reviews Summary for DX Engineering ARAV-4P Active Receive Verticals, 4 Pack |
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Reviews: 5
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Average rating: 5.0/5
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MSRP: $796.00
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Description: The DXE-ARAV-4P Active Receive Antenna array package contains 4 of the DXE-ARAV-1P Active Receive Antennas. This package is intended for use with the DXE-RFS-1P Receive Four-Square system to build a Four-Square Receiving Array. The FVI-1 Feedline Voltage Injectors are not included as the RFS-1 has provision for powering the active antennas.
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More info: http://www.dxengineering.com/Sections.asp?ID=117&DeptID=12#Top
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write your own review of the DX Engineering ARAV-4P Active Receive Verticals, 4 Pack.
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DL6LAU
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Rating: 5/5
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Feb 2, 2006 02:24
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Performed like 200-240m long Beverages
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Time owned: 0 to 3 months
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First: We (DL4LAM - Peter, DL6LAU - Carsten, SM6CNN - Anders, SM6CMU - Ingemar, SM6DOI - Staffan,) are not connected to DX-Engineering in anyway - in fact it was the first time I 'went shopping' at DXE ...
But: As both SM6DOI and me are selling amateur radio products here in Europe, we are always looking for products to distribute ;-) ...
As early adopters, DL4LAM and I were very interested in the RX 4-square from DXE. Somewhere (on the Internet?) there was the claim it will work like 240m long Beverages but will 'only' need a 41m x 41m footprint for optimum
performance on 160m.
Unfortunately there were not many 'real-life' reports found.
2 weeks ago DL4LAM and I placed the order for an
- DXE-RFS-1P Receive Four Square with Controller
- DXE-ARAV-4P Active Receive Antenna, vertical configuration, pack of 4
- DXE-RPA-1 (optional preamp)
- some small stuff like connectors and the like ...
Than the big question for me (living on a 30mx30m lot) was were to put them to try ... To make it short ... I decided to visit Staffan, SM6DOI close to Gothenburg. Staffan is well known for his 160m expertise, he has a 50m tall vertical to transmit (very close to the Baltic Sea (Swedish West coast) and 8 Beverages for RX.
In detail these are
0° 180m long
60° 180m long
120° 240m long
180° 200m long
240° 240m long
300° 200m long
All up 1,5 meters, 9:1 ferrite balun, terminated with 460 ohms, Ground rods are one meter at the terminated side and three metres at the feed point. All coax is RG58. Ground under the antennas is wet blue clay.
Uli, DJ2YA was kind enough to measure the exact velocity factor of the used RG-6 coax (0.84 in our case) so I could cut the delay lines as explained in the manual (you can download these from DXE if you need more details) and installed the so called 'Snap n Seal' connectors - btw - these connectors are great an so easy and quick to assemble, never saw them b4 in Europe ...
Thursday morning I loaded the car and drove about 700km to meet Staffan. He and SM6CMU had already prepared some wooden pallets (still a lot of snow on the frozen ground in SM) with a short
aluminium tubing for the active vertical elements. They also had positioned the palettes that the side length of the 4-square was 135ft (41.15m) and that 2 of the elements were
pointing to 310° (resulting in 40°, 130°, 220°for the other directions).
A 1m ground rod was used at each vertical. When I took out the 102in (2.6m) 'long' whips Staffan and Ingemar were looking rather amazed. This should work like a 240m long Beverage - hard to believe ...
The RX4SQ was positioned about 100m from the shack and about 200m from the TX antenna. One of the Beverages was close to one element of the RX4SQ (within 3m or so) and an unused 10m tower was about 20m away. Other than that the 4SQ was on an open field ...
The installation went very quick. Back in the shack we had an ORION I and a box were the Beverages could be selected. The same box had another RX input and we connected the 4 position switch for the RX4SQ to this input. This
allowed us to instantly switch between the 2 antenna systems for A - B comparison.
As it was still daylight we checked the performance on the OK beacon on 1854kHz. The result was amazing. The F/B of the RX4SQ was very good (25-30dB) with a very clear forward lobe. Ok, it was still daylight, probably it will only work nice at day ;-) ...
But also when dawn came, we had the same results ... The signal output of the RX4SQ was lower than the Beverages but there was not a single case were the RX4SQ would have lost a QSO compared to the Beverages. We than tried the
optional preamp from DXE and signals got stronger (with more or less the same SNR). It was more a personal taste ... I liked the 'stronger signal',
some others from the test crew didn't ...
We only made a handful of contacts during the first day of the contest spending hour after hour comparing the Beverages against the RX4SQ.
We compared the antennas quite some time on signals from NP4A, PY7ZY, 6O0N, VP9I, KG4SB, 9N7JO, PJ2T, HA7TM/HI9, HS0ZDJ, W's, JA's and the result was ALWAYS the same ... The difference was VERY SMALL in most cases, sometimes the Beverage was 'a little bit' better, sometimes the other way round. Very often there was really no difference.
The second contest night brought the same results. After sunrise we disassembled the RX4SQ and I took another 8 hour drive back home ....
So talking about the comparison at the SM6DOI QTH, the RX4SQ worked like advertised and MUCH BETTER than we all thought. One might say that maybe Staffans Beverages do not work well but looking at his results on 160m I think they work (quite) good (on his very good ground). Maybe it was an advantage to have the RX4SQ on very good ground also ...
There would have many more tests possible but a long weekend is just too short ... We thought about reducing the side length in the second night to 70 feet and see how the system works with this spacing but this would have caused some more work in cutting the delay lines to the new length. 'Social commitments' did not make this happen - maybe next time ....
We did some listening on 80m and 40m too and 80m seemed to perform very well with the spacing we used too. On 40m the directivity was very low but the array was still very good on receive (always compared to the above mentioned Beverages)
For us, the performance was truly outstanding for 4 phased 2.6m long whips.
Hope that all the details did not bore you, we wanted to give you some more insight about the installation rather than saying
"THE DX Engineering RX 4-SQUARE WORKS GREAT" ... (although this would have said it all)
Well done Tom and DXE ... Maybe I will add some more thoughts later ...
We enjoyed listening to your signals (no VK, ZL, W6 heard here)! I will gladly answer questions about 'our installation' and the like if you have
some ...
Regards,
Carsten, DL6LAU (and DL4LAM, SM6CNN, SM6CMU, SM6DOI)
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WN3V
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Rating: 5/5
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Jan 15, 2006 04:53
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DX-cellent in My Book!
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Time owned: 0 to 3 months
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Living on almost 90 acres of North-slope mountain land, I have plenty of room for antennas. The problem is it's mostly rock, rugged and anything but level! Our home is at 900 ft. AMSL built in the middle of a timber track. The ARAV-4P is ideally installed on in-the-clear-flat-land. Less than a 10% elevation difference between the 4 array elements. My installation parameters were ANYTHING but that! After speaking with a very personable, honest and helpful rep at DX Engineering about the particulars of my "potential" purchase and install, I bought the package under the caveat of a less-than perfect install scenario.
I could tell as soon as I opened the boxes that this was one well-designed and constructed system. "If it works half as good as it looks, it's gonna be super!", I said to myself. The quality of the documentation for the system is second to none- giving virtually every detail for installation and "optimization" of the array in clear and concise terms. Intending to use the system for 160 and 80m, I went with the 98 ft. per side array dimension. The most time-consuming task is associated with measuring, cutting and crimping-up the flooded RG-6 delay and feedlines. DX sells all the needed cable, connectors and tools needed to accomplish this with a minimum of effort. Being an active (amplified) array, it must be located far-enough away from your high-power transmitter to prevent overload and faliure of the pre-amp's located in the active elements. I chose the "flattest" mountain-side land I could find located 600 feet from my shack. I mounted the 4 elements on 5/8 inch, 4 ft. copper-clad ground rods driven-into the rocky earth about 3 1/2 feet. This is obviously anything but an optimum RF ground condition! I hooked-up the feeder cables and ran the 600 ft. plus RG-6 back into my shack. You need a single 12 volt d.c.line to power the array,(ground-return is via the RG-6 sheild)- so I simply used the remains of one of my existing Beverage's as the power feed.
Upon firig-up the array I noticed how "quiet" it was on 80m. An S9 noise-level on my 2-half-waves in -phase at 65 ft or my 67 ft. vertical, 134ft horiz. Inverted-L, was dropped to either no-meter reading at all, or perhaps an S2 or S3 on both the 756 ProIII and RX-340. Signals that were not even perceptible on the existing antennae, were suddenly "in-the-bag". (e.g.- JW9, RV6, TF4 and an IS0.) The directional nulls and peaks are very "hearable" on 80m but not quite as perceptible on 160m due to my less than optimum installation I'm sure. Compared to my 565 ft. terminated Beverage the array is AWESOME. Higher output, better nulls and S/N.
Although I do have fair output from the array without a pre-amp, I did purchase the RPA-1 and am using it at the receiver input. It does help on the very, very, weak ones but not at all needed if you simply don't look at the s-meter. This antenna is all about S/N and directivity. You can have an S9 QRN level with an S7 or even 5 dB over 9 signal using a dipole or inverted-L. Or you can go to the active array and have absolutely no indication of QRN on the S-meter- but an S-3 or S-5 signal in the clear. I'm sure some of this is due to the fact that the array is located 600 ft. from my house in the middel of the forest and a quarter mile away from power lines and noise sources, but the directional nulls are deep and allow me to "notch" the QRM at the source- the antenna.
I could not be happier with the product. It's perhaps a bit pricey but it is a complete system THAT WORKS- and it works exactly as marketed and sold. To me, that's priceless!
I can only imagine how-well the antenna would perform when installed under even marginally optimum conditions, compared to my rugged/compromised install.
Enjoy and 73.
John, WN3V
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W0MU
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Rating: 5/5
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Nov 23, 2005 16:25
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Amazing
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Time owned: 0 to 3 months
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This system is truly magical!
My installation uses 70 foot sides. The array is installed over very old river bottom ground. There are tons of river rocks in the ground making ground rod installations difficult. I used two ground rods per antenna. The ground at the time was moist from recent rains and snows, otherwise it is good ole Montana clay. I don't know how good or bad the the ground is.
This antenna was used extensively during the 2005 Sweepstakes SSB contest. It made 75 and 40 meters much more fun to work. Being able to select different directions was great.
There is obvious nulls and peaks in the 4 directions. I would say that the forward direction was equal to the 330 ft beverage that I used last year. Unfortunately the beverage was great to the direction it was pointed.
We were multi op and one of the other ops was quite skeptical as we were installing it. He was very impressed after using it.
Prior to the contest I worked numberous western europe stations on 75m under very poor band conditions from Montana. A number of ZL stations were heard as well.
A preamp is not reguired as there is plenty of signal.
I just wish I could put a transmitting 4 square this easily!
If you are looking for an upgrade on the low bands give this antenna some thought.
The boxes are well made and professional in look and quality.
Excellent
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NQ4I
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Rating: 5/5
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Nov 10, 2005 04:50
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Best directional antenna yet!!
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Time owned: 0 to 3 months
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I have had the system for 9 weeks, and have had the opportunity to compare them side-by-side with my 800 ft beverages...the receiving 4 SQ has better F/B and F/S than the beverages period! The receiving 4 SQ allows you to NULL out an interferring station, and the DX signals peak rather dramatically in the proper direction. If you need beverage quality low band receiving antennas and real estate is a problem, then this antenna is for you! I used the 98 foot spacing and was amazed at the performance on 160 meters and 80 meters too! The receiving 4 SQ was real impressive in the Broadcast band also!! Signals were heard on frequencies at sunrise in 4 different directions that were 20 db over S9 and on the same frequency! My receiving 4 SQ shows good directivity even up to 40 meters! A very well designed product and its performance is amazing for its size...performance equal to or better than 800 foot beverages in such a small package!
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W3UA
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Rating: 5/5
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Nov 6, 2005 21:48
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Great receiving elements for low bands.
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Time owned: 0 to 3 months
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See also my review of the DX Engineering Receiving Four Square Antenna Switch. Antennas used in 4-sq receiving array, 98 feet spacing. In my QTH the soil is poor (Granite State!), and two of four verticals are just over solid rock. So I use 8 buried radials per antenna, 20 feet long each. I also purchased DX Engineering receiving preamplifier, which works well, but in my case it is not necessary, since the antennas themselves provide more than adequate signal. So far, everything works great.
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