| K2ORS |
Rating:  |
2007-04-27 | |
| Junk |
Time Owned: more than 12 months. |
Worthless junk. Poor quality construction. Signal from my 80m Isotron was 12-20dB BELOW my 80 meter mobile! You are immediately tipped off that something is wrong when you open it up and there all kinds of warnings that they won't take it back!
Be wary of extremely hyped and enthusiastic reviews - remember it may be the best antenna someone has - but compared to what? You can make some contacts with a light bulb for an antenna!
If you are pressed for space use a mobile whip w/ a counterpoise wire.
73 Warren K2ORS
WD2XGJ (137 kHz)
WD2XSH/23 (506 kHz)
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| VA3WYC |
Rating:  |
2007-04-27 | |
| Finicky |
Time Owned: 3 to 6 months. |
| Used the 40 & 20 meter models on the 19th floor balcony. Neither worked at all. Spent countless hours adjusting and tuning to no avail. Considering the many who are very pleased with their antenna, I'd say the design works in certain conditions and falls flat on others. The trick is to know which one works and which one won't so it's a bit of a gamble with your money. Take the risk if you're up to it. |
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| KJ5FS |
Rating:      |
2007-04-21 | |
| Great little antennas |
Time Owned: more than 12 months. |
| I have 15m and 20m Isotrons inside my house, and they work amazingly well considering where they are. I have 95 'countries' on the 15m and about 50 on the 20m (I think the low height hurts the 20m more). Waiting for the sunspots so I can get more! Have gotten Kyrgyzstan, Angola, etc. I am very pleased, and will likely try the 40m and 80m versions soon. They are very sensitive to tuning, but the results are worth it. And they aren't out in the thunderstorms. |
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| VE7MBW |
Rating:     |
2007-01-24 | |
| Works great as a ground floor condo antenna. |
Time Owned: 3 to 6 months. |
| My wife and I are both hams and we live in a ground floor condo. We have tried numerous compact 80meter antennas (loaded whips, small loops etc.) with generally poor results. We recently tried the Isotron 80 and had no problems hearing signals and checking into nets 1000 miles away! The antenna is not equal to a full size 80m dipole 100ft in the air but is certainly the ultimate condo stealth antenna for balcony mounting (hence 4/5). Our antenna is mounted at only 5ft above ground with a small aluminum mast and a 4ft ground rod at the base of the mast. We spray painted our Isotron green to blend in with the ivy covered wooden fence it is mounted on (also prevents rain from changing the resonant point). The tuning worked exactly as specified in the instructions and was simple. When asked by the condo "cops" what it is my wife tells them it is a bird house! Tks de VE7MBW and VA7MDM |
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| MAXWELL_MOON_EX_K0MAX |
Rating:      |
2006-12-15 | |
| Amazing on 160M |
Time Owned: 0 to 3 months. |
With a new Bilal Isotron 160C at 35' in the 2006 ARRL 160 Meter contest a few days ago, I worked 34 states & 5 provinces. What makes that amazing for me is that my QTH is in the middle of what QST magazine, in its report on the 2005 contest [p.104, June '06 issue], called the "black hole of Minnesota." And also that I had to use the Isotron for RX as well as TX, was on the air for less than 13 hours, logged QSOs by hand, worked as a "Single Operator" without any type of assistance, & ran only 5 watts (QRP).
The 160C was amazing but not without limitations. Most glaring, I had only one QSO with a California station & none with Florida; forget all the hams operating there, it was just too far for 5 watts from this antenna. Also, and as many others have noted, Isotrons are VERY hard to tune: despite six trips up the tower & trying every strategy suggested in the manual, the SWR is still too high for me to operate on the bottom 25 kHz of the band (the true home of QRP CW on 160M).
But the limitations of the antenna aren't as critical as the limitations of my QTH: a tiny treeless lot in the middle of a city in the 160M RF black hole of Minnesota. For me to operate on 160, it was the Isotron or nothing. That's why I'm amazed by what it did do much more than bothered by what it didn't. |
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| N5TEY |
Rating:     |
2006-12-06 | |
| Great antenna |
Time Owned: more than 12 months. |
I have owned an Isotron 40 since May 2005 and an Isotron 80 since April 2006. I found that for the cost and ease in mounting the Isotron is an efficient antenna. The Isotron is not a substitute for a yagi at a 100’, but provides a good alternative for those without a large amount of space to mount a large antenna.
The instruction manual from Bilal is sort of basic. The tuning of the Isotron is a little tricky sometimes. I have found that the swr that I received with the antenna closer to the ground wasn’t necessarily what I found once the antenna was mounted in the air, but many antennas are this way as well. I also found that I had to modify my grounding for the 80m antenna.
The little antennas receive a lot of curious looks from neighbors. They think the antennas are some sort of TV antennas, and then I tell them that the little antenna has allowed me to work the South Pole they all say “wow, with that?”
I have read reviews in the past that state that you can’t work DX with an Isotron. This is not true. I have worked ZS, S0, 5A, XF, CN, Antarctica, and many other DX stations with my little Isotron's.
The only negative is the instruction manuals and the tuning instructions. The manuals could be made a little more user friendly. However, we have to learn to be resourceful as amateur radio operators, so the Isotron seems to be consistent with our need to be resourceful.
The Isotron is a good buy and a good practical antenna. Will you win a CQ WW contest with an Isotron? No. Will it provide you a good practical alternative to a much large antenna? Yes, most definitely yes.
73,
Steve N5TEY
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| N6BIZ |
Rating:      |
2006-10-20 | |
| incredible |
Time Owned: 6 to 12 months. |
| for those of you who say the isotrons dont radiate today at 0255 after 30 minutes i cracked the xf4dl major pile up on 40 cw with 100 watts and only 35 feet up thank u 73 i would say they work . |
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| NS6Y_ |
Rating:   |
2006-09-06 | |
| Hmmmmmmm....... |
Time Owned: 0 to 3 months. |
I got a couple of these with the manuals and catalog at a ham fest - I never deployed them since I got them for resale. However, the workmanship is "eh" at best, we're talking MFJ level of "crapmanship" here.
I'm sure the antennas work, since the way they're recommended to be deployed, you're radiating off of the shield of your coax and perhaps a bit off of the mounting pole too. As a vertical. Verticals work very well when there's at least one counterpoise and really well if there are a bunch. All the Isotron is, is a tuned circuit up at the top of the vertical.
Considering the elementary level of craftsmanship needed to build one, it's probably not too hard to build your own - in fact this type or class of antenna could be the basis for an interesting paper in QST or QEX. |
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| AG4YO |
Rating:     |
2006-09-06 | |
| After 5 months... |
Time Owned: 6 to 12 months. |
Well I have used my Isotron 80 for 5 months now and it still works good. I recently attended the Shelby Hamfest and talking to my AM buddies, they were commenting how good my signal was from Mississippi (see review below- Isotron 80 mounted in my attic).
I have an Alpha-Delta DXCC in my attic as well and on 80m, the Isotron works better. It is more quiet and signals are about 2-3db better. I had used the DXCC mounted outdoors when I lived in Pensacola and it worked great on 80m.
Folks, this ain't no full sized dipole or yagi, but I'll attest to the fact that if you want to get on 80m and you don't have the room for a big antenna, this little guy works pretty darned good.
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Earlier 4-star review posted by AG4YO on 2006-04-11
This antenna isn't a 3 element beam on 80m. That's the bad news. The good news is that it is as good as many dipoles I have had. I moved into a neighborhood where the Nazis roam. I mounted an AD DXCC in the attic and an Isotron 80.
The Isotron is bolted to a 3' piece of pipe which is ty-wrapped to a 2X4 in the dead center of my attic. The 2X4 was courtesy of the air conditioning people as it was used as part of the support for duct work. My attic is about 15' tall in the center and this 2X4 is about 7 feet long. I feed the antenna with 75' RG8X coax that runs across the attic to the eaves, out a hole, down the brick, into a hole into my radio room.
I put 5' into the radio room (including drip loop) and coiled the rest (about 30') into a neat 6" coil ty-wrapped outside the house. I feed my Swan 350 and 1200x amp to it thru an MFJ tuner and coax switch, and the other port on the coax switch goes to my B&W 5100 with an SB200 amp thru another MFJ tuner. The two tuners let me tune one for AM 3885 and the other for SSB 3955. Of course, use low power to tune and always tune for minimum SWR, NOT max power. Tuning amp outputs and then the tuners soon yeilds rated power at minimum SWR.
Construction and Tuning the Antenna
Construction is easy. About 10 parts max to put together. Bolt the radiator plates to the plastic side insulators (be sure hole in insulator is closest to coax plug). Screw the long studs into the coils with double nuts to sandwich the wire from the coil. Attach the coil to the radiator plates in appropriate holes. Screw the wire from the coax connector along with the wire from the bottom of the coil together using the hole in the insulator as the tie point. Mount the PVC mounting pipes to the radiator plates. All hardware (with a few extra) are included. The two "L" shaped rods are for tuning...more on that next. You're ready to attach to pipe and mount! Instructions are overly complicated but follow them as you do the above things.
Tuning the Antenna
Not a big deal. Where in the band do you operate? 3.860 Voice and above? Forget the tuning arms. CW? use one tuning arm for mid band and both for the lower part of the band. Truthfully, if you're using a tuner then one tuning arm will work.
Not using a tuner? A little more tricky. Mount the antenna and you'll have to use the info above plus trial and error (unless you have a resonant point locator like the MFJ antenna tester). Rotating the tuning arms will handle the fine tuning. But HOW YOU MOUNT THE ANTENNA EFFECTS THE TUNING. Basically the tuning arm (down in bottom mounting position and up in the top mounting position) lengthens the antenna. You can download the manual from Bilal off the net for free to see what "top/bottom position hole" means.
Performance
Most everyone can't tell the difference between my signal now at the new QTH on the Isotron and my old QTH in Pensacola on the dipole. I have only used it for a couple of days now, but so far so good!! No TVI, no garage door opener trouble, no alarm system problem all with 350w AM or 500w SSB.
Grounding
The antennas ARE NOT grounded in the attic. I have a ground wire that attaches to both amps and both tuners, then out the hole (about 12") to a 6' ground rod. Hardly a "proper" ground. The coil of coax helps keep any stray RF out of my shack. Your mileage may vary but I have no problems with loading without a ground.
EMF
Didn't measure it, but my high and clear mounting in the attic helps. The mounting point is directly over the den so the minimum point (right under the antenna) is where my wife sits to watch TV. Most of my 500W work is at night after she is in bed on the other side of the house. Just be aware of this issue and if you only use 100w then you should have no problem. I have neon bulbs below and in proximity of the antennas and they do not glow.
Anyway if you live in "Fatherland" subdivision, thumb your nose at the Covenant Gestappo and have fun! The Isotron can help. |
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| K5RIX |
Rating:      |
2006-06-22 | |
| It really works fine |
Time Owned: 0 to 3 months. |
Forget Marilyn Monroe, et. al. My logbook indicates there is signal being radiated by my Isotrons. Mine are on a steel mast clamped to a balcony railing up about 70 feet.
I wrote a pretty glowing review of the MFJ model 1622 "Apartment" antenna (4/5) and it earned it. But I got tired of the counterpoise wires all over the balcony, and I REALLY got tired of my better half demanding they go away. OK. Now I have had the 20M and 40M Isotrons up a few weeks. They are better than I initially reported.
The Isotrons are a rare bird. Totally outside the box, yet completely within it. After a couple weeks using the Isotrons A LOT, I must say they are most likely better than anything near their size. Plus, there are no radial counterpoises. They make a neat installation that looks like a hi-tech bug zapper.
My installation is a 20M plus 40M on a six-foot mast clamped to my balcony railing. Resonating the 20M model is super simple: you swing the bottom arm into position for max signal. The 40M model I dunno - mine came out at about 7.02 which is perfect for me. But by removing the wire that connects the bottom capacitor plate to the mast one can raise the resonant frequency. These antennas are quite forgiving if you give them just a little room to breathe, i.e.: in the clear in just two dimensions.
The proof is in the operating results, and I have worked everywhere I could have hoped plus a couple others. Being in a large steel-reinforced concrete structure tends to attenuate signals from certain directions, but not that many in my case. As far as I can tell, the only places I can't work from Yokosuka are South America and south Africa. But who knows? Running 50 watts on CW I have worked the USA, Philippines, Australia, Indonesia, Sri Lanka, Hong Kong, Saipan, Taiwan, plus the usual South Koreans and Russians.
The Isotrons may not be the final answer to anybody's DX dreams, but they work better than ANY antenna I've tried here, and they do not require wire running all over the place.
I am a believer now.
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