Comet CHA 250 BX

[KF5HVM]

I'm new to HR and have a Yaesu FT450 running into a Comet CHA 250BX. On an earlier thread the respondents were generally critical of the antenna for being non functional and overpriced. I won't argue the price issue, but what I want to know is what should my expectations be of a "good" vertical antenna? I am subdivision restricted so a diapole or yagi are out of the question. Since this antenna was installed I've worked the following from south Texas: ME; CT; VA; MD; GA; FL; most of the south;
northern CA; etc. etc. These contacts were made on 40M & 20M.
What do you say?

[WB2WIK]

Everything works to some degree.

I've worked Ohio from here in Los Angeles using a 60W light bulb for an antenna.

The only difference between one that makes contacts and one that makes thousands of contacts is degree of effectiveness.

[NA0AA]

No antenna can defy physics, and some verticals are better than others.

The CHA matching system is a type of dummy load, which keeps the SWR low by absorbing the reflected energy before it goes into the feedline.

Secondly, a vertical with no radials is half of an antenna typically - there are some commercial antennas that are center fed dipoles.

In the same vertical footprint, a taller radiator with an active antenna coupler at the base, equipped with a field of radials should easily ourperform the CHA. 30-31' will work from 40 and up, 43' will work on 80 and up [although 15 and 10 meter performance starts to get wierd]

If you are really limited to vertical antennas, and only one, I'd take a good hard look at stealth antenna designs - depending on your house perimeter, it may be reasonable to put a loop or a bent dipole under your eaves, or in your attic space. Certainly small VHF/UHF antennas are canidates for attic mounting.

It would be worth your investment to buy some antenna books and look at them with an eye to possible designs that could be used at your location. You can hide verticals in trees, if you have them, for example. Attic mounted dipoles on a two-story house can be effective [provided the roof is not an RF shield].

I would suggest you keep the CHA for a while, and try to erect a stealth antenna or two, such as a 20 or 40 meter vertical in a tree if you have 'em, and compare the two antennas directly. At that point, you can make your own decision and will be able to proceed from there.

[W8JI]

I work Europe on 160 meters SSB from my mobile with an antenna less than 1% efficient.

99% or more of my power goes into heat, yet I can still on occasion work stronger Europe stations on 160 SSB.

On the other hand I can go in my house on the same night I can work five or six Europeans on 160 SSB from my mobile, and work hundreds of Europeans one right after another.

If I never had the house antennas I would think my mobile antenna was working good. I would also think the 160 meter band was rarely open to Europe, and that three or four contacts in a night was good.

You have exactly the same thing. You can work people and that makes you feel good about the antenna. That's because you don't really know how a good antenna would work.

If you enjoy it, be happy. Just don't ever convince yourself it is a good antenna, because it isn't.

73 Tom

[KF5HVM]

Thanks for the input. My antenna is mounted on a second story deck about 20 feet from the shack. I do have trees and they surround the antenna. My attic is fairly shallow and full of equipment and the roof tiles are concrete.
If I stay with a vertical, can you recommed anything more effective than the comet?

[M0GVZ]

Thanks for the input. My antenna is mounted on a second story deck about 20 feet from the shack. I do have trees and they surround the antenna. My attic is fairly shallow and full of equipment and the roof tiles are concrete.
If I stay with a vertical, can you recommed anything more effective than the comet?

Imax 2000 for 15m-10m. If you're wanting to get round the world, make your own quarter wave groundplane vertical for the 20m band.

[KJ3N]

If I stay with a vertical, can you recommed anything more effective than the comet?

Cushcraft R8, but you'll lose 75m.

[WB2WIK]

If you have trees, I'd recommend using them and ditching the vertical on the deck idea.

Trees are free towers for wire antennas.

[NA0AA]

Thanks for the input. My antenna is mounted on a second story deck about 20 feet from the shack. I do have trees and they surround the antenna. My attic is fairly shallow and full of equipment and the roof tiles are concrete.
If I stay with a vertical, can you recommed anything more effective than the comet?

In my previous response.

[W8JI]

Thanks for the input. My antenna is mounted on a second story deck about 20 feet from the shack. I do have trees and they surround the antenna. My attic is fairly shallow and full of equipment and the roof tiles are concrete.
If I stay with a vertical, can you recommed anything more effective than the comet?

Something like an R7, a Butternut, a 5BTV, or almost anything made for ham bands with traps would be much much better.

How big of an antenna can you put up? Don't you have room for a dipole?