eHam
eHam Forums => Antennas, Towers and more => Topic started by: N8TI on March 18, 2023, 03:53:46 PM
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There has been a lot of discussion about the Elecraft antennas
They have a new one, the AX2 that is a base loaded antenna for 20 meters. Has anyone ever modeled that antenna and determined its efficiency? Thanks, Joe
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On 40 meters about 15 dB less gain than a dipole at ten feet.
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"its efficiency?"... Its a small coil telescopic whip. The "efficiency" is determined by the counterpoise radial system, and they supply a single radial. 20 watt rating max.
-Mike.
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I have the MFJ-1899T, a close cousin to the AX2. Like Mike said the magic is in the radials, as with all verticals. I mean, its a ground mounted, loaded vertical feeding it with 5 to maybe 15 watts. It works ok for a compromised antenna and certainly can be setup in minutes.
If you're operating portable and have the time and wherewithal, I'd consider an endfed dipole or a mag loop.
GL/73
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It is extremely inefficient compared to a simple dipole. They are neat for a simple table top antenna if that is all that you can use. Do they work? Sure they do. Check out K4SWL on YouTube. He tries all kinds of radios, antennas and the little Elecraft antenna is one he uses from time to time.
If there are no trees to tie off to for a simple dipole?…...Get a painter’s pole from one of the big box stores and use it for a mast. Get some rope for guys and erect a simple 20 meter dipole. It will do much better.
If only a table top antenna is what you can use, than get the following telescopic antenna....18 foot telescopic whip.
https://www.aliexpress.us/item/3256801746922028.html?spm=a2g0o.cart.0.0.7d0d3c00X7IWhi&mp=1&gatewayAdapt=glo2usa4itemAdapt&_randl_shipto=US
Pick up a small camera tripod, make a mount for the above antenna and add four ground radials for 20 metes. Both the dipole and the telescopic whip will give you a very low SWR so you can cover the entire band without an ATU.
Barry, KU3X
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Not trying to be a tool.... You could tune a random wire laying on the ground and get more contacts.
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For the same effort the K3MT grasswire would actually work better.
Both being -12DB antennas, short whip of 150ft or wire on the surface.
The latter would be far less fussy and easily rolled up and stuffed in a pocket.
Allison