RE: [amsat-bb] Dual Dipoles for Echo?

[<alan_bloom@xxxxxxxxxxx>]

Why not use a gain-type omnidirectional antenna like a collinear?  (Often used for repeaters or home stations)  You could still tilt it so the radiation pattern "donut" tracks the arc of the satellite's path.

Al N1AL

> -----Original Message-----
> From: owner-AMSAT-BB@amsat.org [mailto:owner-AMSAT-BB@amsat.org]On
> Behalf Of David Rush
> Sent: Thursday, November 11, 2004 7:26 AM
> To: amsat-bb@amsat.org
> Subject: [amsat-bb] Dual Dipoles for Echo?
> 
> 
> Dragging my Arrow antenna (with elements sticking out every direction) and 
> camera tripod out to work Echo, along with having to track it, is getting a 
> bit old.  I've come up with the idea to build two simple dipoles (2m & 
> 70cm), mounted some distance apart on a piece of wood or Plexiglas, with 
> the elements parallel (Sort of a lop-sided H shape).
> 
> In prep for a pass the thing would be oriented so the donut-shaped patterns 
> would hit the arc of the satellite's path across the sky.
> 
> Advantages: no re-aiming during the pass, and a bit more compact than the 
> Arrow, should work better than a vertical for high-elevation passes.
> Disadvantages: lower gain than the Arrow.
> 
> Any ideas how far apart the two dipoles should be?  The Arrow has them on 
> the same boom, but the driven elements are 20-30 cm apart and they're 
> polarized differently.
> 
> Would there be an optimum distance off the ground each dipole should be in 
> order to take advantage of ground reflection?
> 
> Any other thoughts on this?
> 
> David, KY7DR
> ----
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org