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Reviews For: Hi-Z Triangular Vertical Array Receive System

Category: Antennas: VLF/LF/HF Receive only

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Review Summary For : Hi-Z Triangular Vertical Array Receive System
Reviews: 3MSRP: $705.00
Description:
This system was designed to utilize 3 shortened antennas with
Hi-Z amplifiers as a directional receiving antenna.
Product is in production
More Info: http://www.hizantennas.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0035
W1MU Rating: 2018-10-23
Excellent System Time Owned: more than 12 months.
I have used Hi-Z receive arrays, starting with the four element Hi-Z 4 (a square, 60’ on a side) and then moving to the three element Hi-Z 3 (a triangle, 50’ on a side) because it fit on my property better. The bulk of my comments below will pertain to the Hi-Z 3 and my experience has been almost all on 80m, and though I used the original element pre-amps that Hi-Z provided when the system was first introduced I have migrated to the newer PLUS6 designs. I have been impressed with the Hi-Z 3 and recommend it.
My Hi-Z 3 array works well. Eight years ago I began playing around with basic Beverage designs on 40m, where experimentation is easy because dimensions are more manageable. Like many low band operators before me, I was stunned at the improvement in receive ability. On 40m – after years of wire antennas, vertical arrays, and some serious yagis – a 145’ Beverage based on K1FZ hardware surprised me at how such a simple, inexpensive receive antenna could make such a big difference. I then played around with 300’ and 450’ Beverages on 80m, which also worked well. But I also learned their limitations – they aren’t steerable, they take up a lot of space, winter animals get snagged in them, and the need to put them up in the fall and take them down in the spring was wearing on me. I tried a Hi-Z 4 array and saw that it was a very viable alternative to Beverages and solved all the problems that Beverages presented – they WERE steerable, I COULD leave them up all year, and winter animals managed to leave them alone. I then swapped the Hi-Z 4 for a Hi-Z 3 and spent three years doing A/B testing between it and some 450’ Beverages, and though the testing was not “scientific” I concluded that the Hi-Z 3 array “heard” every bit as well as the Beverages AND it had all those other benefits. For the last two winters I have not put up my Beverages and now I have no plans to ever do so again – the Hi-Z family of receive antennas will be my low band receive antenna choice. There are other things worth knowing – one is that this is an antenna that “wants to work.” The owner of Hi-Z, K7TJR, cautions against abuses – for example, he advises that the antenna should be placed clear of other antennas, metal, and trees. But in my experience with the antenna, as well as from posts from other owners, the system is “forgiving” and these antennas seem to do just fine when located in compromised places. Mine are near, and even right under, trees and close to other antennas. Though it’s possible that a detailed analysis, with near and far-field signal sources, and some sort of informal antenna range, would reveal shortcomings it sure doesn’t feel like I’m giving up anything. In summary, the Hi-Z 3 has made casual operation on 80m much more of a pleasure and has also enabled me to get more serious in working DXCC countries that I never dreamed possible on 3.5 mHz – countries like XW, HS, BY, S2, XX9, VK9C, and 9M2 – all hard to work from W1 on ANY band.
K7TJR has made it easy to install and operate one of these arrays. Though there is ample reading available on the theory behind these systems if one wishes to pursue it, the Hi-Z array will work quite well if one just follows the directions laid out in the user manual. There are very few rules that need to be followed, and from my experience all that needs to be done is for the (1) element spacing to be as precise as possible, (2) RG6 coax feedlines from the array controller to the element base amplifiers to be equal, and (3) length of the short delay line on the controller to be consistent with the spacing of the elements (all this is explained in the manuals). Perhaps the only challenge you will face is in fabricating the vertical elements that compose the array itself. Hi-Z makes this easy by selling, through DX Engineering, a kit for building 24’ elements. I elected to fabricate my own and use 18’ elements, which seem to do fine, and system performance is not hypersensitive to whether you use 24’ or 18’ elements.
Superb product support is provided by the company owner, Lee, K7TJR. Lee is quite passionate about the technologies used in his products and he’s committed to making his users happy and successful with his arrays. The product line has evolved in response to feedback from users, he’s responsive in answering technical and operational questions, and he’s very patient with those of us prone to making self-inflicted errors or who fail to read manuals. In short, Lee is a good guy and he stands behind what he designs and builds.
By the way, if you got this far in the review, one question you might ask yourself is whether you ought to just go with a Hi-Z 3, instead of considering bigger and more complicated arrays (like the Hi-Z 4). Well, I implied that I wasn’t going to get into any antenna theory, but there’s one concept worth knowing about called “receiving directivity factor,” or RDF (see W8JI’s website). This is a case where “more is better,” and by going from a three element array to a four element array you gain enough directivity to make the change worthwhile. But that may not be for everyone, and you might just find that the three element array improves your life enough to install it and leave it alone. And by the way, with 50’ sides on the array’s triangle I have found that it receives well on 160m, 80m, 40m and 30m.
Hi-Z arrays are available through DX Engineering, and they are responsive in filling orders and getting the product to you as fast as possible. Give a Hi-Z array a try, I believe you will be pleased with the outcome.
AA6VB Rating: 2014-01-31
Wonderful System Time Owned: more than 12 months.
I bought this system when they first came out several years ago and have used it regularly since.

I live on a small city lot, no more than a quarter acre. I have tried a dozen receive antennas over the years looking to improve the all important signal to noise ratio. Nothing gave a meaningful improvement. Along came the 3 Element Array, so I thought I'd give one a try.

Everything about my situation is a compromise. I can't get a 40 foot triangle with equal sides, one of the elements is 3 feet lower than the other two, the corner of the house blocks the line of sight between two of the elements, two of the elements are near a metal fence and one of the elements is within 50 feet of my vertical. Not a pretty picture.

Still, the system is highly directive on 160 and 80 meters where I spend most of my time. It provides a very good improvement in signal to noise ratio over my vertical and has truly uncovered another layer of signals for me. It REALLY does work, even with all the compromises in my situation. I am amazed at its performance and am VERY happy with the decision to install one.

There is a REAL solution for city lot owners with challenging situations.

I can also run the legal limit with no harm to the array - a great feature.

This works great and is highly directive on the high bands as well, and signals that are barely readable on my SteppIR Vertical become Q5! It's like having a beam.

Highly recommended!

73,

Bob/AA6VB
KA1J Rating: 2014-01-30
A marvelous receiving antenna system Time Owned: 6 to 12 months.
Taken from the Hi-Z website the description reads:

"This system was designed to utilize 3 shortened antennas with Hi-Z amplifiers as a directional receiving antenna. This new and unique circuit configuration uses Tri-Phase combining for extra accurate phasing and amplitude stability. This system uses only one delay line and provides a form of time delay phasing that provides more than one band coverage with the Hi-Z elements. This system was designed to operate over the 160,80, and 40 meter amateur bands but can be used from below the broadcast band to over 30MHz. A typical 50 foot square layout of 20 foot tall elements and Hi-Z amplifiers can provide 9.3 dB of Relative Directivity Factor and 30 dB of front to back ratio on 160 meters. Of course the best performance depends on the accuracy of the antenna layout, the accuracy of the connecting and phasing cables, and any interfering nearby structures."

I live in an area where there is a lot of line noise generated from the 25KV power lines Amtrak uses to power its trains. Until they went electric, this was a perfectly Rf quiet location for ham radio. Unfortunately that is forever history as my antennas are within 100 feet of these lines. Listening to the low bands with an Inv-L is difficult at best but add the power line noise, it's painful on the ears. I use a K3 with diversity and use the Rx antenna in the subreciever.

I made both a pennant and a flag which did help somewhat but did not give me the directivity I needed when I needed to quickly listen in different directions such as in a contest. I tried a magnetic loop but there are multiple locations the interference is coming from and though the loop was very helpful on the dual/diversity Rx and has a very small footprint, I decided to give a try with the Hi-Z Rx antennas which require more space. There are several different systems to choose from: 2 element, 3 element, 4 and 8 element systems. I chose the triangular array which provides 6 switchable directions.

I find the Hi-Z triangular system to be the best Rx antenna I have used thus far; it genuinely gives amazing front to back rejection of unwanted signals and a decent improvement in forward directivity. It was put to the test in the recent CQ 160M CW contest and I was able to hear numerous EU stations clearly and also hear the much louder US stations on the same frequency. The Inv-L could not hear most of the EU but the Triangular certainly did. To work this DX I ended up turning the diversity off on the K3, linked the Sub Rx & main receivers and turned the volume down to zero on the main Rx. Doing this meant I could only hear from the Hi-Z in my one ear. By shutting off the main Rx, I was no longer hearing with the Inv-L and with that, the triangular array knocked the stateside signals low enough I could hear even more EU because of the high front to back ratio nulling out the US stations. It was really surprising how effective it was. And you select directions at the turn of a rotary band-switch.

The higher in the bands you go, the less front to back you experience but for someone who can not put up a beam, this almost causes me to feel like I have one. I worked Amsterdam on 10M using the Hi-Z & the K3 in diversity. There was a marked improvement in the reception of this signal in the K3 using this Rx antenna and the 160M Inv-L (which I use for the 10M transmit antenna). I could barely hear FT5ZM on the Inv-L but it was much more understandable with the Hi-Z. Blending both antennas in the K3s diversity mode and they were Q5.

Sales are now through DX Engineering but the information on the Hi-Z website will answer most of your questions. I have no affiliation with either DXE or Hi-Z other than I bought this antenna system and am very pleased with it.

http://www.dxengineering.com/