| G1HSM |
Rating:  |
2022-06-15 | |
| A useful little device which works very well! |
Time Owned: more than 12 months. |
Got one of the EARCHI Matchboxes some years ago when they were shipping internationally but never used it until yesterday when I thought I'd try it.
Strung a random wire across my top floor room and connected it to the Matchbox. Connected the Matchbox to my IC-7300 via my LDG Z-100A tuner using about 8' of coax (screen providing the necessary counterpoise) and tried it out. Checked SWR on a few bands and it tuned OK, giving close to 1:1. Had a few QSOs round Europe on 20 and 17 m SSB and got 58 and 59 on most of them. I don't have a garden so I use indoor antennas. Do have a balcony and might try to put a wire up there.
I was putting 100 W through it, which is the maximum power rating. Shorter lengths of coax can be used with a counterpoise wire - a terminal for this is provided. Noise levels, rather high with indoor antennas, are about the same as my indoor 40 m hor. V (which I use on 40 and 20) and a hor. V for 10 m). I know that one shouldn't use a 40 m dipole on 20 but it works!
A friend of mine in Paris visited his cousin in Hawaii and was given a Matchbox. He uses it with a 31' wire on his roof and gets loads of CW contacts.
It's just a 9:1 unun in a neat little box and is rather expensive. The money is going to a good cause, however, and it works very well. |
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| W4FID |
Rating: |
2021-11-04 | |
| a good portable/low impact/simple antenna |
Time Owned: more than 12 months. |
| I have used mine in several portable locations during the past 3 years. See my W4FID/P bio for some of my operations. This has always traveled with me and been the primary antenna at some of them. I get it up about 15 feet high with the wire running up a simple telescope mast and then out to whatever the other end can find in whatever direction there is something. QRP up to about 15 watts from an Xeigu 108G with a manual tuner for a couple years and now my IC-705 with an LDG AT-100PROII tuner. Usually a 75 foot run of coax. No counterpoise or radials ever. I work it on 40-30-20-17-15-10 on FT8, CW, and SSB. 40 does surprisingly well for a short, low, simple antenna. The higher freq bands do very well when they are open. LDG tuner gets it to 1.1:1 most of the time and 1.3:1 at worst. I work tons of QSOs easily and lots of DX. Some of it pretty nice like Sardinia, Lebanon, Corsica, Baleric Isl, Malta, Andorra, Jersey, a few of the Greek Islands. All of the US states with ND, SD, WY, ID, MT, AK several times each. Even use it QRP on SSB and check in to some nets. BOTTOM LINE IS IT'S EASY TO PUT UP, LOW VISIBILITY, WORKS WELL, AND IS NOT TOO EXPENSIVE. |
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| K6SDW |
Rating: |
2021-11-04 | |
| I'm impressed |
Time Owned: more than 12 months. |
Why I chose the EARCHI kit. I live, by choice, full time in an RV park and we're not allowed to have any antennas outside of our very small RV pad...sound familiar? So, the 9:1 random wire end fed is as good as it will ever be for me...or a small ground-mounted vertical.
Of course you'll need an antenna tuner, but I've had surprising good results with the supplied 30' wire. 10 - 80 meters. The antenna is a bit squirrelly on 30meters.
The club guys will respond to any questions you may have.
Cheers All!
Update to my review from last March 2019, I added 50 more feet of antenna wire and my end-fed antenna really came alive, especially NVIS! Now, if I hear them, I can usually work them. Referencing RBN my signal strength on any of the working bands has increased overall. For the price you can't beat this antenna. This antenna is barely 20' in the air and zigzags around my RV space.
Using the MFJ-939i tuner I've worked 80 - 10 meters and late at night I consistently work Asia, Europe and South America...so please don't tell me end fed antennas don't work!! Yes, I agree it's not as efficient as the 1/2 wave end fed, but again my LoTW log is proof the EARCHI antennas works. |
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| KC7YE |
Rating: |
2019-03-07 | |
| Should do the job |
Time Owned: 0 to 3 months. |
| Wanted to stream line my set up for portable operations, primarily Washington Salmon Run & 7th Call Area QSO Party. Decided to give EARCHI EFW a shot. First surprise was when I ordered last Friday, received Email 2 hours later that antenna was ready for USPS pickup. Arrived in western WA in Mondays mail. Looked as advertised and this morning ( Wednesday) mainly because it was perfect antenna weather, snowing, hooked to existing +/- 43' EFW and counterpoise made of random lengths of scrap wire on ground. Easy tuned on all bands 80 -10 including WARC bands with an old MFJ 948. First try was on 30 mtrs FT8, bingo answered a CQ from IU2DMI for first QSO ! This is from just north of Seattle. Worked a couple more W, K stations. QSY to 17 mtrs and a couple more stateside QSOs. Happy so far and when snow stops will rig up the supplied wire. Total setup time was 10 minutes by a 77 Yr old, looks like will meet my needs and for the price is worth exploring. |
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| MW1CFN |
Rating: |
2018-03-29 | |
| Very good |
Time Owned: more than 12 months. |
Let's start with the obvious: this is a simple wire antenna designed to be cheap and easily deployed from one support. It's not a Yagi. It's not designed for 2kW.
It's often the case that finding a number of suitable vertical structures to support a dipole or other antenna is difficult or simply impossible. It's often the case that we need reasonable performance from a simple multiband antenna. It's often the case we need an antenna that fits in the pocket and costs little.
That is what this EARCHI antenna is for. I've used them for years where more complex arrangements aren't possible (e.g. portable). It won't be as effective as a monoband 1/4 vertical, but it won't be too far off and, of course, it covers at least 60m-6m easily, even from an internal ATU, and without the complexity of two other wires that need a lot of room (the radials).
It is what it is: simple, multiband, reasonably effective. |
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| KK5R |
Rating: |
2017-10-04 | |
| Great Antenna — replaced other antennas |
Time Owned: more than 12 months. |
This is the preferred antenna here. Last contact was with a guy in Slovenia on 20M...
KK5R ENDFED DIPOLE
I made a 9:1 UnUn using a couple of ferrite cores designed to go over RG-8. It uses 9turns of hookup wire following the pattern used in the EACHI design. The image shows the antenna layout. I can use it without a tuner from 160M to 6M but there is a big thing to keep in mind: You have to be careful how you dress the feedline.
At first, I dressed the feedline straight down from the UnUn. The SWR was not good and the lower two HF bands (160 & 80 Meters) were unusable. In fact, the feedline dressing is critical. Then I tried dressing the feedline down under the "counterpoise" by bisecting the vertical and the horizontal, hanging it down approximately 45-degress from the counterpoise. I also included a 1:1 Balun that uses ferrite beads and this was enough to make the antenna usable from 160M to 6M. While the SWR is less than 2:1 all across the bands, I still use the FT-450AT's internal tuner to finesse the system.
The wire used is #14 house wire for the 16-ft counterpoise and #14 copper clad steel wire for the 53-ft section. The 20-ft of feedline connected between the 1:1 Balun and the 9:1 UnUn is composed of an 18-ft length of RG-8X coax which is connected to a 2-ft RG-58 pigtail coming out of the UnUn. The feedline to the shack is RG-8.
One other consideration is that it is isolated from any surrounding metal objects. If this is not done, the SWR could well be affected.
Note that I also have experimented with wire wound trifilar wound coils on 1-1/4 inch sections of PVC pipe and while they worked, they were best between 80M and 12M, the other bands were not very good. While PVC wound UnUns work, UnUns wound on ferrite cores seem to be more desirable because they measure better at lower and higher amateur bands.
KK5R
You can see the antenna here:
https://forums.qrz.com/index.php?threads/build-your-own-9-1-unun-antenna-on-the-cheap.579701/page-3
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| W1GOV |
Rating: |
2016-07-05 | |
| works great for me |
Time Owned: 0 to 3 months. |
| I have had my license (General) for just over one year. I live in an HOA restricted community and have been forced to use an old wire dipole (originally used for SWLing) in my attic for HF. It worked OK on 40 meters and I was able to make almost 70 contacts over the past year in casual operation. However, there are only about 3 DX stations in that list. I thought I would try the EARCHI end-fed as it looked like it would not be noticeable in my back yard; especially since I have no neighbors to the rear. I was astounded with the improvement. Within minutes after completing the installation I made a contact in the Balearic Islands with a reported 59 signal. Before, where I heard mostly noise on the bands I am now hearing stations. Just this weekend I have contacted 11 of the 13 Colonies Special Event. My rig is an ICOM 7000 and I am tuning the antenna with the LDG-7000. This antenna is certainly worth the $56 donation. |
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| SMAUG |
Rating: |
2014-12-14 | |
| Works well on 10-40m |
Time Owned: 0 to 3 months. |
(EARCHI = Emergency Amateur Radio Club of Hawai)
I'm a new General, and this is my first HF antenna, so I can't compare it to other anntennas. But I CAN tell you how it works for me.
STATION:
- Kenwood TS-440S/AT
- MFJ-949E manual antenna tuner
- 100' of DX Engineering RG-213/U coaxial cable
- Copy of a Kenwood MC-43 microphone
- Radiator wire is 31' long, hung vertically in a tree, about a foot away from the trunk
I live in the Chicago area and have made lots of contacts on 10m with this so far, after only a couple weeks. (10m contest this weekend, as I type this) Alaska, California, Oregon, and Washington were no problem. The guys with the 1.5 kW and a yagi on a tower walk right over me, of course, but once they've worked the station and have moved on, I'm in like Flynn.
I'm using this as a semi-permanent installation from my ground floor apartment, hence the long run of co-ax. The installation had to look neat so it doesn't draw extra attention. I installed it during the night, ninja-style. ^_^
In my 31' length, my built-in tuner will tune it to less than 1.2:1 SWR on 40-10m. Haven't tried 6m. Using my external tuner, I can match it to 80 and 160m, but haven't made any contacts yet. I'm told it is because the antenna is very inefficient at this relatively short length on those bands. Even so, I feel like this was a great value.
Anyway, it is an effective and inexpensive multi-band HF antenna. All the old hands tell me how inefficient it is, but all their alternatives either take up a load more space (dipoles) or cost a lot more, but look to be the same thing.
I considered a magnetic loop antenna, as they're said to work great and don't even need a long radiator wire. However, they spendy ($400+), need constant tuning, and develop lots of voltage. Much more complex to build home-brew, too.
I think for apartment-dwellers and for field operations, this is maybe the idea antenna.
As for my rating, I gave it 5 stars because it represents such a good value. It is effective, inexpensive, and space-efficient, and that makes up for any lack of efficiency. |
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