Tuner free 43' 10-80 meter 500W ProMaster HF base antenna

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prcguy

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I have not used that specific model but I will say in general, most of the Alpha HF antennas are compromised and low performance, except for maybe their newer loop antennas. In the past they have had blatant false advertising and outright lied about a few of their products which are no longer in production.

Most of the Alpha wire and whip type antennas are a 6:1 to 9:1 transformer feeding various random length radiators. For what the antenna in question costs you can do much better in my opinion.
prcguy

For what the antenna in question costs you can do much better for a lot less.
prcguy
 

K7MEM

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Most of the Alpha wire and whip type antennas are a 6:1 to 9:1 transformer feeding various random length radiators. For what the antenna in question costs you can do much better in my opinion.
prcguy

For what the antenna in question costs you can do much better for a lot less.
prcguy

I am not familiar with this antenna, or the antenna company, so I read the promotional material, the reviews and the manual for the antenna. After that, I pretty much agree with "prcguy". The good reviews (5 by 5) on eham are not out of line with that type of antenna. The basic setup shows the 13 and 25 foot elements deployed along with the ground wire. Without anything in the "matchbox" those lengths are ok for the bands above 40 meters, but useless for 40 and 80 meters. To make it useful for 40 and 80 meters, a impedance transformer is necessary. The impedance transformer also helps to smooth out the impedance excursions on the higher frequency bands.

Will the antenna work? Sure. But so will a home made Random Wire End-Fed with a impedance transformer. And for a lot less money.

I have a 92 foot End -Fed that uses a 9:1 homebrew Balun at the feed point. It tunes all bands (160 through 10 meters) with a SWR less than 1.5:1, with a tuner, but is a little iffy on 30 meters. Overall it works very well.

For some magic numbers on random wire antennas try the following:

With a 9:1 balun and 53 feet of wire you should be able to tune 160 through 10 Meters with a SWR of 2.2:1 or less. See the link below.

http://www.balundesigns.com/content/Wire%20Lengths%20for%204%20and%209-1%20ununs.pdf

A good ground wire is needed.

Of course, that's just my opinion from the available literature.

Martin - K7MEM
 

ranger821

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Thanks for the honest thoughts. I have a windom that is up about 38 foot and works fairly well but it's into the leaves and limbs of the sycamore tree and the maple tree. Instead of the alpha antenna, I may just have the trees trimmed back so the wire is out of the limbs.
 

prcguy

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Have you ever noticed a positive review of an Alpha or Chameleon antenna where they compared it to another antenna of known performance? I have not and usually the positive comments are "I contacted some great far away place on 20m with my new bla bla antenna". If you think about it, when 20m is open you can take around the world with a few watts and a limp noodle and the fact that an Alpha XYZ and 100w did it means nothing.

If you were to take the same basic layout as the Alpha "tuner free 43ft" but use a common 64:1 transformer and enough wire to make the whole thing about 63ft long, you will have a resonant antenna (without a tuner) on 40, 20, 15 and 10m that will put the Alpha to shame. And you can make a 64:1 transformer that will handle 800W for about $20.
prcguy


I am not familiar with this antenna, or the antenna company, so I read the promotional material, the reviews and the manual for the antenna. After that, I pretty much agree with "prcguy". The good reviews (5 by 5) on eham are not out of line with that type of antenna. The basic setup shows the 13 and 25 foot elements deployed along with the ground wire. Without anything in the "matchbox" those lengths are ok for the bands above 40 meters, but useless for 40 and 80 meters. To make it useful for 40 and 80 meters, a impedance transformer is necessary. The impedance transformer also helps to smooth out the impedance excursions on the higher frequency bands.

Will the antenna work? Sure. But so will a home made Random Wire End-Fed with a impedance transformer. And for a lot less money.

I have a 92 foot End -Fed that uses a 9:1 homebrew Balun at the feed point. It tunes all bands (160 through 10 meters) with a SWR less than 1.5:1, with a tuner, but is a little iffy on 30 meters. Overall it works very well.

For some magic numbers on random wire antennas try the following:

With a 9:1 balun and 53 feet of wire you should be able to tune 160 through 10 Meters with a SWR of 2.2:1 or less. See the link below.

http://www.balundesigns.com/content/Wire%20Lengths%20for%204%20and%209-1%20ununs.pdf

A good ground wire is needed.

Of course, that's just my opinion from the available literature.

Martin - K7MEM
 

kj3n

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Aug 19, 2013
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An 80m doublet costs about $30-$50 to make (depending on material) and would beat the snot out of that Alpha antenna. With the proper tuner, it will handle legal limit all day long.

Why are people so afraid of tuners?
 
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