[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: c-band TVRO dishes for AO-40

On Wed, 8 May 2002, Charles Suckling wrote about using a 3m TV dish:

> ... you will need to adjust the "elevation" with a second
> actuator.... My system allows 0 - 35 deg elevation...

AO-40 is always just a few degrees above the geo arc (except at perogee).
And it doesnt change.   So there is no need for elevation adjustment other
than a bolt and a wrench once you find the sweet spot.

The best approach is to mount your S-band feed about 6 degrees above  your
C/Ku band feed and then the dish can be used for both TV and AO-40 with no
elevation changes...  I use a paperclip to mount my S-Band feed to the
edge of my TV feed so I can move it around the edge and that way get any
offset I want from 0 to about 5 inches.

Once you find the sweet spot, it should stay that way except for when
AO-40 is very close to earth, and then you dont need the 3m gain anyway...

See photos on http://www.ew.usna.edu/~bruninga/ao40ant.html

The TVRO dish photos links are in the "related subject" line...

de WB4APR, Bob

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org