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Reviews For: Comet CHA250B

Category: Antennas: HF: Verticals; Wire; Loop

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Review Summary For : Comet CHA250B
Reviews: 138MSRP: 449.
Description:
The Comet CHA250B broadband vertical antenna will amazingly cover 75/80 meters through 6 meters with no gaps! Transmit range is 3.5-57 MHz and receive range is 2-90 MHz. SWR <1.5:1. This 23.5 foot vertical requires no radials and weighs only 7.1 lbs. The antenna consists of five sections of aluminum tubing that slide into each other. The bottom section has the matching network built-in. Only two simple measurements are required during the easy assembly. It can handle 250 watts SSB and 125 watts FM. SO-239 input. Mounts on a 1 to 2 inch mast (not supplied). Rated for 67 MPH wind survival.

Product is in production
More Info: http://www.cometantenna.com/amateur-radio/base-antennas/multi-band-hfvhfuhf-2/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
24.51383.7
N5PHT Rating: 2013-03-13
Poor Time Owned: 0 to 3 months.
I was looking for an antenna to take with me on camping trips in my RV. We are sometimes gone for several months at a time and set up for a
week or more so I wanted something that was not too difficult to set up and take down. I wanted something that has auto band changing so I don't
have to move or reset anything. I had mostly been using my Tarheel screwdriver antenna. The Tarheel performance is fine for being on the road
but I was connecting a coax to the tow truck and would have to unconnect everytime we moved the truck. So, something I could use portable that is compatiable with a 40 foot 5th wheel RV with autoband switching was in order.

After reading the reviews on the CHA250 I was not decided and knew the CHA250 was indeed a compromise but felt it certainly should outperform a screwdriver antenna. The CHA250 has 24 feet of aluminum in the sky. (note: I was only mounting this antenna 20 feet into the air on a pole)

I assembled it very easily and could see how portable is very possible with this antenna. I then zipped around the bands and to my delight the SWR was great from 80 meters to 10 meters just as promised! However, the signals
were very, very low. I then drove my truck around to the base of my tower and set up so I could try A/B switching at the home station (I have a tower mounted coax switch). I was using three antennas: The CHA250, the Tarheel
Screwdriver on my truck and a 66 foot random wire (sloper for 80 meters).I switched around using different inputs on the antennas to rule out any problem with coax connections. The SWR being excellent probably means the antenna is assembled correctly and working per specs.

The Comet was at least 3 full S units lower always than the other two antennas on several bands that I tried including 15, 17, 20 and 30 meters. Much of the time the Comet was 5 to 7 S units lower. Really, the Comet would be S2 and
the Tarheel S9. Huge difference bewtween the antennas. I found one station that was about 1 S unit lower on the Comet than the Tarheel but other comparisons were terrible for the Comet.

Some suggested this antenna should be grounded and/or have radials. I did not try either because it was supposed to not need them. And I would not want to use radials at a campground - the purpose of purchasing this antenna. I was surprised to find a ring for attaching guy wires - but no mention in the one page instructions on guying or if it should need guying.

And I would not have purchased the antenna if I knew it needed guying (or does it?) Comet includes a guy ring so I suspect the answer is "yes."

So, this antenna arrived at about 1 pm and was in the box for shipment back to the distributor the next day. If you want an antenna that has great SWR and can work a station or two this antenna would probably be fine. But if you can put up even a mobile antenna that seems better in my limited experiments.

The autoband switching and the ease of assembly is a plus but the performance being lower than a few dollars worth of cooper wire really lost me in this deal. I can't always find a tree at the campground for that copper wire and the use
of the Tarheel on the truck with no autoband switching is difficult but so far my best solution for RV'ing seems to be to hope for the right trees or use the Tarheel. I may end up mounting a Tarheel to the RV with an electric arm or something...the search continues and CHA goes back for a refund.
KG7AVF Rating: 2013-03-06
60 day update Time Owned: 0 to 3 months.
Having used the antenna solidly for 2 mos now, my impressions remain positive. The sweet spot for SSB at this QTH is 15-20. 40 and 80 have a lot of loss, but are workable. I still go to my bazooka dipole for 10m. An unanticipated surprise - the lower power requirements of digital modes like PSK31 have allowed me to fully utilize the lower 30-80 bands of the antenna. I've had solid DX QSOs from New Zealand, Japan, Russia, Hawaii and Alaska, Caribbean, and SA to Brazil and Argentina with this antenna. No, it won't outperform corresponding monoband dipoles. No, it won't come anywhere close to the performance of a directional 11 element HAARP Jr. at 90 feet. Given realistic expectations and awareness of the strengths and weaknesses, it's a good general use antenna that provides acceptable performance for someone running less than 250 watts who needs to get on the air and may have QTH limitations.
KF4LVC Rating: 2013-02-26
Great for get-on-the-air & go! Time Owned: 6 to 12 months.
I did some horse-trading with a friend for this antenna. My goal was to use this antenna in the various "field" setups I operate each year, particularly working with the Boy Scouts in their radio merit badge courses. I was to understand that the CHA250B was considered a compromise antenna. As an RF Engineer, I would agree that any antenna which relies on a wide-banded matching scheme would not be expected to perform well.
However, the first time I deployed the antenna, I was pleasantly surprised.
The antenna's construction is rugged and lightweight. The sections nest within each other, except the very top section. Setting up the antenna takes 15 minutes or less.
During this occasion, I set up the antenna for the BSA Merit Badge University, held at a local community college. I had to mount the antenna at ground level. The location could not have been worse; it was in a small area (maybe 20 ft by 50 ft) between 3 campus buildings, several stories high. I did not have great expectations of making many contacts. Yet, when I fired up the radio, I found that the antenna did indeed work all bands with low SWR. Better yet was the very low noise level I experienced. But I reserved my judgement until after I made some contacts.
Well, if the CHA250B is considered a "compromise", then I became a lover of "compromise" antennas after a day of great contacts. I was able to work any station I could hear with very encouraging signal reports sent back to me. I worked plenty of US stations & the Caribbean. I also had no problem working some European DX on 20M & 17M in the middle of the day. The antenna made a perfect partner to my Icom IC-7000 that day!

I really like this antenna. I know it cannot compete with large verticals or full-sized yagis. But don't let anyone tell you that you cannot use this great little antenna for some fun DX!
K0DQN Rating: 2013-01-02
Solid performance, low profile Time Owned: more than 12 months.
General:
I've had the CHA-250B for over a year. I do a lot of listening, maybe two to three QSO's a month. 95% of the time it operates about 10 feet (3m) AGL on a Rohn 30' telescoping mast (see my QRZ page for photos). After dark, I can run up another section of the mast due to HOA restrictions. This is a relatively "invisible" vertical, and my HOA association has told me that if they don't receive any complaints, they won't push the issue.

Here in Kansas City, we get our share of "wind events" usually from thunderstorm/squall line gust fronts, and the odd tornado that strays close by. My antenna has held fast during confirmed 50kt gusts, and it just bends as reed in the wind and appears no worse for wear.

Performance:
I have a simple setup: A Yaesu FT-450D and the Comet. RX appears to me to be wonderful, but I have no basis for comparisons either rig or antenna. I have had QSO's from stations in New Zealand and Italy, hear plenty of stations calling. Limited to no more than 100 watts from my rig, and even if I could push out the 250w limit for the Comet, I can't compete with full power, BeamSmasher 6000's, so it is condition dependent.

If you need a portable vertical, or one that generally "disappears" to keep a low profile, I would definitely consider this antenna.
VE7DLC Rating: 2012-12-22
Excellent stealth antenna! Time Owned: more than 12 months.
For what it claims to be, and is, it works very well. I've used it in residential neighborhoods for years, and have worked all over North America and into Japan (from the west coast of Canada). I've had the best results on 20 meters (even QRP), but also use it on 40 and 80 meter nets. Currently I have it mounted approximately 25 feet in the air. If you need an antenna that takes up little space and is unobtrusive, then this could be the one for you.

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Earlier 5-star review posted by VE7DLC on 2012-04-17

I have used this antenna in multiple locations for over 5 years, and it just works. I didn't want an antenna that would take over my property, and I certainly wanted one that would be easy to install. The Comet fits the bill.

I don't understand a lot of the negatives that I've read about this antenna, particularly the ones that complain about the difficulties of contacts. I've installed it at ground level, roof level and higher, and it's performed adequately for each location (with no radials). I enjoy vintage gear, and with a Yeasu FT-107, Yaesu FT-757 and other similar transceivers I've worked throughout North America (I'm on the West Coast) and Japan.

So no, it's not a great DX'ing antenna, but why would you buy it in the first place if that's what you want to do? It continues to give me what I want out of an antenna - the ability to communicate - and that's what it's all about.
PU2NBU Rating: 2012-11-19
Fair Enough Time Owned: 6 to 12 months.
Easy installation (im my case, 33 feet high)

Got me on the air

Excellent RX

Windproof (fortunately, no tornados neither hurricanes in my brazilian region)

Gets good or reasonable signal reports

It is a keeper!

As a Class C 100w operator, my next step will be also to install a Dual Beam Pro with an Yaesu rotor to chase DX on 10 meters. I will report about this later on, after the first 6 months from this future installation.

W4AFK Rating: 2012-11-18
Good buy if you know what to expect Time Owned: 0 to 3 months.
I needed a broadband HF antenna not limited to ham radio frequencies (non-ham experimental, FH & wide band High Speed data). It needed to be ALE friendly and cover the entire HF spectrum. So I bought this CHA250Bx and it "does the job". It's ~30 feet up and compared to dipoles, it's just as "good" (definitely not better).

- Is it a DX antenna? No.
- Is it super efficient on 40/80? No.
- Is it relatively flat across the HF bands? Yes.
- Does it work? Yes!

If you have limited space and want to get on the air, this antenna should be considered. However, just remember that it is NOT as good as dedicated ham radio verticals or to well installed wire antennas. BUT, it gets you on the air and works also on non-ham frequencies with no tuner (SWL, Utilities, etc.)
W2NJU Rating: 2012-09-15
Realistic Expectations Time Owned: N.A.
What were hoping to accomplish with the CHA-250B. It does what it is advertised to do which is get you on the air with an swr under 1.6 from 6 meters thru 80 meters. It is a highly compromised antenna which puts SOME signal on the air while wasting more as heat. It's the trade off with a broadband antenna. For some operators this is the only way to get on the air. By their own admission, Comet tells you this is NOT a DX antenna although many have successfully worked DX with it. It's a decent antenna for the operator who wants to make contacts, rag-chew and not deal with grounds and radials. If you can put up a simple wire antenna or 43 vertical with some buried counterpoise wires you're better off.

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Earlier 3-star review posted by W2NJU on 2012-07-28

The CHA-250B is an antenna option which I have been considering. I have a small back yard and am opposed to having a 43 foot vertical popping up and having to have a few radials. The XYL is not crazy about having a dipole over the back yard. Therefore, a low profile, radial less, no tune vertical seems like a good idea from THOSE standpoints.
Mick Stwertnik from Comet Antennas described it as basically an end fed long wire mounted vertically with a base transformer providing the impedance match. By his own admission much of the RF is converted to heat and lost but it is the price paid for such an antenna. I have had many e-mails from guys who have had good results with it anyway, especially if it is mounted at the suggested 35 feet. Mick said mounting it lower introduces more substantial ground losses. The coax shield becomes the counterpoise. I suggest reading K3DAV's review and check out his log book on QRZ...He's had some very impressive contacts.
It is totally unfair to compare this antenna with a dipole, log periodic or Yagi. For many, it is the difference between getting on HF or putting the radio back in the box. For others, they like it's simplicity, low profile and no fuss operation. For many of these operators it's not about the S-Units but rather being able to make contacts and many log books suggest it does that quite well. The most egregious thing about it is the price which is totally outrageous. Many hams are retired while others have been hurt by the economic downturn (depression?)and $400 is an ouch! I would urge Comet to rethink the price point.
KP4EC Rating: 2012-09-09
not good at all Time Owned: 3 to 6 months.
worst antenna ever had! on my personal opinion it's too much money for the pice of aluminum youre are getting! i won't put money on the dumpster like that again!
N8NN Rating: 2012-07-28
Update on my previous review Time Owned: 6 to 12 months.
With this antenna mounted on the rear ladder of my motorhome I worked HK0NA in Feb 2012 on all bands 10m-400m, and on CW, SSB, RTTY from Florida using 90 watts, 50 watts on RTTY. I added a line isolator near the transceiver to eliminate RF feedback caused by not having a good ground connection. All contacts were made with this DXpedition through huge pileups.

The Comet CHA-250B worked great!