| N8YN |
Rating:      |
2011-01-26 | |
| I LOVE IT AS IT WORKS GREAT FOR ME! |
Time Owned: more than 12 months. |
I USE IT FOR MY GARAGE SHACK HF OPERATION. IT IS ON A 6' MAST PIPE AND 4' OF IT IS IN THE GROUND. THE ANTENNA IS ONLY 2' ABOVE GROUND AND WORKS GREAT.
I AM HAVING A LOT OF FUN WITH IT WORKING STATIONS ALL OVER THE WORLD. NO TRAPS OR RADIALS, A LAZY HAM'S VERTICAL (ME). SO WHAT IT WILL ONLY HANDLE 250 WATTS...I AM NOT A CONTEST PERSON OR LOOKING FOR THE DXCC...JUST A RAG CHEWER LOOKING FOR A GOOD QSO WITH 100 WATTS OR LESS. |
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| K4PBY |
Rating:     |
2010-11-11 | |
| Very good |
Time Owned: 0 to 3 months. |
| Antenna assembled easily, all parts fit correctly, quality was excellent. I installed the vertical to a metal fence post about 3 foot above the ground. SWR on all bands met or exceeded specifications. Performance on 30,20,17,15,12 and 10 meters has been excellent. On these bands it usually outperforms my doublet antenna. Performance on 40 meters has been good. I would say 80 meter performance is fair. Overall I am very pleased with this antenna. |
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| 5B4AIY |
Rating:  |
2010-10-28 | |
| Poor performance in less than ideal circumstances. |
Time Owned: 3 to 6 months. |
I purchased the Comet CHA-250B antenna because my lot is fairly small, which precludes anything more substantial. The manufacturer's reccomend that it be mounted at least 35' (10.6m) high. In my case, this was impossible, and the best that could be done was with the base of the antenna about 6' (2m) off the ground on a wooden post. In addition, the ground here is very rocky, situated half way up a small mountain, and extremely dry and of poor conductivity, even the local electricty supply does not use ground rods because they are almost useless.
The materials are of excellent quality, complete with stainless-steel hardware, and easy to follow instructions. No tuning adjustments are required. The manufacturer's provide a VSWR plot of the antenna's performance, and claim that the VSWR is no higher than 1.5:1 over the range 3.5 - 75MHz.
In my case, using a RigExpert AA-230Pro antenna analyzer the VSWR was indeed essentially flat from 3 - 30MHz, which raises an interesting point. With this length of whip, 23.8' (7.13m), there should be strong resonances at several frequencies. The only way these resonances can be supressed is if the matching unit is fairly lossy. Thus the designers have optimised the RF match rather than attempting the ultimate in RF performance.
The antenna has now been in use for about 5 months, and in all that time I have not managed to work anything. No-one, not a single contact! I also have an MFJ-1786X magnetic loop antenna, upon which I will comment in another review, and connecting these two antennae to the Ant 1 and Ant 2 inputs of my Kenwood TS-2000 it is a simple matter to perform an A-B comparision. On receive, the Comet is never better than the magnetic loop, and in most circumstances is between 1 and 3 'S' points lower in signal strength. Since the MFJ only works from 10 - 30MHz, my observations are limited to mostly 20 metres. On transmit, I can certainly work stations within a radius of about 2,000 kms to 3,000 kms reasonably well, receiving signal reports varying from S4 to S7, but when switching over to the Comet antenna, I receive negative copy reports, or, at best, extremely weak, virtually unreadable. I have tried adding radials, but there is no improvement in performance.
To be fair, the antenna is obviously not mounted in accordance with the manufacturer's reccomendations, and, perhaps if it were to be mounted on a 35' mast or steel pole this may act as a counterpoise and give better performance. However, in my situation, I cannot do any better. Reading other reviews, it is clear that some have obtained quite satisfactory results from this antenna, and if anything is to be learned my from experiences, it is that when used in less than ideal circumstances its performance is very poor. Often more is learned from our failures than our successes.
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| G0VQY |
Rating:    |
2010-10-10 | |
| At least you will be able to talk to people |
Time Owned: 0 to 3 months. |
Be under no illusion that this is nothing more than a compromise antenna. Performance is extremely mediocre and a simple wire dipole at low height will outperform it completely in most cases. However, if you are looking for an antenna that will enable you to talk to people who are not too far away then this does work. I have found that if I can hear someone, I can normally work them. If they are fairly weak, you may have to shout quite a few times but perseverance normally pays off.
I found the performance was best on 40 m where signals were very strong most of the time. You can also work DX if they are strong themselves and are using very efficient antennas.
As a matter of interest, I compared the antenna to my three element SteppIR. Listening to a station in Lebanon on the vertical that was 52, I was receiving 58/59 on the beam. But that was to be expected and if you do compare this vertical to a more efficient antenna, you are going to be very disappointed. Look at it as what it is, the means of getting on the band fairly easily with a non-intrusive antenna that is easy to install, but don't expect to be able to work lots of DX |
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| N1TNW |
Rating:     |
2010-09-05 | |
| Better than expected |
Time Owned: 0 to 3 months. |
| Purchased this antenna as a start to my new ham station which consists of a Kenwood TS-2000. Wanted something stealth for the time being - antenna works surprisingly well installed on the top of a 40ft tower- made contacts to Poland, Russia, Chile, Columbia in my first few days. I knew this was a compromise and was willing to take the risk prior to spending more money on a beam, rotor etc.. The only frustrating issue is when making contacts and you can only hear one side of a conversation because the other party is unobtainable. I am satisfied right now with this antenna - but will upgrade to a beam in the new year. HF is fun - and this gets you started and makes you hungry for more. If you don't have the space or are limited by deed restrictions - I would definitely buy this antenna. easy to put together and install. Although the price is rather high - it does work well - 20 and 17 meters have been great - trying to fight your way into the big boys can be frustrating - but once traffic slows down you can get in - patience is needed. I am patient - but I am dying to be one of the big boys and take full advantage of my rig. A beam is definitely in the future for me - but as I stated before - this antenna definitely works well. I will be selling mine in the new year - if your interested - drop me an email - I will keep you posted. |
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| VE3BDR |
Rating:     |
2010-08-11 | |
| Just the ticket. |
Time Owned: 0 to 3 months. |
| Bought this with some misgivings, found it to be well made, easy to assemble. Performs adequately. New to HF, just got active again. Landlord issues, no radials, concern about visual aspects. Landlord is happy, I am happy. |
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| N4ABB |
Rating:      |
2010-07-29 | |
| Still works Great! |
Time Owned: more than 12 months. |
| Antenna was installed in 2005, 18 feet above the ground to the feed point on a tip mount. It has only been tipped down once for a hurricane threat. Still operating over 200 Watts. Very pleased with the performance of this antenna for my location. Works as advertised. |
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| K3DAV |
Rating:     |
2010-07-10 | |
| Very surprising, good performer.. |
Time Owned: more than 12 months. |
Let's face it guys. This is a compromise antenna for those poor hams like me that are space restricted. It is not as good as a big yagi or a perfect dipole cut for each band. If I could put up one of those antennas, I would. But I can't , so I use the CHA250B, and it works pretty damn good. And anyone who has used this antenna and said it was trash, you were either installing it incorrectly, or you were expecting way too much from a compromise antenna.
I bought the CHA250B knowing I was getting a compromise antenna, and did not have great expectations for big performance. But I figured it would at least get me on the bands. And it has done just that, but with greater performance than I ever expected. I use (TM) LMR-400 coax for feedline
The base coil is basically built like a big dummy load, to provide a low 1.1 to 1.4 SWR across the HF spectrum, and it does do this as advertised. From 80 meters continuous through the entire HF spectrum into 6 meters, the SWR never goes above 1.4. That is not a joke. Tested with my Icom 746PRO and my MFJ-269 Antenna Analyzer. Power handling is 125 watts FM, and 250 watts SSB. The main element is 23 feet of aluminum tubing in 5 sections, that takes a tap from the dummy load coil to radiate RF. The entire antenna is well constructed, and has stood against pretty heavy duty winds and extreme hot & cold from the Pennsylvania winters, and mean summer thunderstorms.
Comet says it works from 80 through 6 meters and it does. But 6 meters is very poor in both TX & Rec. My GP-15 tribander does 5 times better on 6M. An S-5 signal on the CHA250B, becomes a 10 to 20dB signal on the GP-15. I would not recommend this antenna for 6 meter usage.
As for HF bands, the CHA250B does very well from 80 through 20 meters. I have made several contacts with good reports to Europe, Asia, South America and even Australia and Japan. It also does well domestically. Typical reports are S-7 to 20dB. Normally, if I can hear them, they will hear me. This is more than I expected.
Now for the downside. The antenna works on 17 through 10 meters, but the performance seems to drop off on each band as you move higher in frequency. By the time you get up to 10M, the performance is about half or less than half of the lower HF bands. But it does work. I use a Solarcon I-MAX 2000 for 17 through 10M, and it is far superior to the CHA250B, just from 17 to 10M.
Here is one perk I didn't expect at all but was nice to find. As I said this antenna is designed to work with up to 1.5 SWR from 80M and above. But I tried it out on 160 meters and was a bit surprised. On 160M it has a 3.0 SWR. But the tuner in my Icom 746PRO brings it down to 1.1 and I have talked up to 500 miles away on 160M with it.
The CHA250B also works real well on the 60 meter 5 channels. With just 50 watts, I have talked all over the country and a few stations in Europe on 60M. SWR still sits at 1.2.
They suggest you mount the antenna at least 35 feet off the ground, but mine is on 15 feet of steel mast from the ground. They also say you do not need ground radials. But I cut 2 separate wires for counterpoise's. One is cut for 75 meters, and the other is cut for 40 meters. They are both a 1/4 wave of their bands, and both attached to one of the U-Bolts on the antenna mounting bracket. There was a slight improvement on those 2 bands on my TX signal to several people I talk to a lot. The steel mast acts as a counterpoise for 20 meters. It works great without the wires, but adding them can't hurt.
The antenna is also a great receive antenna for SW radio listeners. I have good receive from the AM broadcast band clear through 30MHz. My only objection is the $400 price tag. I like the antenna a lot, but it probably has only $30 to $40 worth of material in it.
Bottom line; It is a good compromise antenna. You may not give them 20 and 30dB signals in many places, but you will give them S-9 and 10dB signals. You WILL make the contacts that the big boys make. I have broken through pile-ups with guys using big beams and dipoles, and up to 1.5KW of power. And all I had was my 100 watts from the radio and my CHA250B. THEM---HEARING---YOU. That is all that is important. The CHA250B will make that happen. Get one.
And just for comparison, I have known hams who have replaced Titans, and several other HF verticals with the Comet CHA250B, and found an improvement. This antenna is built well and simple. Sometimes simple is just better. |
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| KJ6GEU |
Rating:     |
2010-06-16 | |
| Good compromise |
Time Owned: 0 to 3 months. |
| I bought this antenna for simplicity's sake. I'm a new ham, running an IC-7000 barefoot as a base rig, and really don't want to deal with putting up a tower or a big beam antenna at this point - also, big ugly antennas are somewhat frowned upon in my area. Given my power limitations, it seems to listen and talk pretty well. With a Buxcomm UnUn, SWR is less than 1.2 on all bands from 40m up to 6m, but it's over 2 on 80m and I didn't expect much there, but tonight I had a decent QSO with several hams several hundred miles away on 3.888. It's mounted with the base about 7-8 meters off the ground. Overall, I'd say it's a solid antenna for those of us who can't afford or aren't allowed to put up a monster tower in the backyard. |
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| KA4AIY |
Rating:     |
2010-06-01 | |
| DX is Fine For Me With 250B |
Time Owned: more than 12 months. |
Mixed reviews suggest a lot of hams were poorly toilet trained.. either that or they don't grasp the concept of an all-band vertical in a restricted subdivision. I suggest the nay-sayers live in ground-cluttered areas.. where ground effects attenuate signals emanating from the 250B. I had mine for two years and in two different urban QTH's (60 miles apart and at different altitudes; 3300 and 4300 feet MSL). In both installations I mounted the antenna on a Radio shack mast 15 feet up from ground. I also drove an 8 foot electrical grounding stake at the base. One other item that seem to make a difference was the use of a 1:1 balun (Buxcom Un Un; in-line RFI isolator) mounted on mast at the antenna feed point. I am convinced that ahs an effect as without the swr readings varied and slightly higher. With it the SWR readings are 1.2:1 on all all bands without a tuner.
Running only 35 watts out of a Yaesu 450 allows me to work DX... I recently worked Japan on 17 Meters and the Ukraine. Italy is easy to QSO with also... from here on 17 and 15 meters. I live in Las Cruces, NM; where the ground offers a poor electrical complement via soil and desert dryness.
I offer these comments to balance the reviews as to many hard core types want to trash what admittedly is a compromise, but works for em and obviously others. Perhaps the varying experiences are based on location... and economics. the bottom line: The 250B is trouble free, hassle free vertical compromise that for what ever reason... works for me... even on 40 meters. So lighten up Hustler lovers.. have a radial install party... I'll stick with the 250B. My "4" rating is based on my belief that a "5" would mean perfection... an absolute... and as noted, all shortened verticals can only be evaluated as metaphors for urban living... IE compromises.
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