1. 10 Ribs attach to the central steel hub
W7HR's
1. 10 Ribs attach to the central steel hub
2. Arrangement of ribs from top of assembly platform
3. The elevation worm drive
4. The steel Az-El mount and antenna assembly platform
5. A closer look at the azimuth drive
6. A closer look at the elevation worm drive
7. Near-complete antenna with aluminum mesh installed
8. Structural rings attached to rib
9. Arrangement of rings between ribs
10. Closeup of underside of antenna
11. Closeup of the azimuth drive, showing the drive motor
(from a linear actuator), the potentiometer and shaft coupling to the worm
gear, and the two limit switches.
12. A closeup of the elevation limit switches and part of
one of the counterweights. A total of 300 lbs. of lead and steel are used
for the weights.
13. Method of attachment of the feed supports. More bolts
will be added after alignment!
14. A cradle was constructed to hold the feed. The threaded
rod extending out the back is used for securing the plastic cover.
15. Another look at the feed cradle support assembly.
16. The feed lays in the cradle and is secured with hose
clamps.
17. A view of the feed and support assembly as seen from
the work platform.
18. The feed with the antenna switch and preamp installed.
19. Overall view of the antenna showing the 8-foot work platform
and the plastic cover. The antenna is pointed approximately west in this
view. As you can see, my view of the sky is a bit restricted to the west!My name is Randy Stegemeyer and I am located near Seattle, Washington. I have been interested in 1296 EME for many years but only recently have been able to find the time to do anything about it. I am nearing completion of a 5.2 meter dish which I am planning to use for 1296 Mhz EME, as well as for some radio astronomy activities and satellite listening. The antenna has an Az-El mount and was built mostly from TVRO components. The elevation drive was made from a horizon-to-horizon drive for a 16-foot TVRO dish, and has an integral worm drive mechanism. It is driven by a 90-vdc linear actuator motor/gearbox. The azimuth drive is a roller-chain arrangement connected to a sprocket on another worm drive. This worm drive is also driven by a linear actuator motor/gearbox. The antenna will use potentiometers (to start with) for position feedback and will be controlled with a "data acquisition" board running on an old 286 PC.
Electronics includes a KB2AH 1296 Mhz preamp and feed horn, and an ICOM R-7000 receiver. After I have all this working I will move on to the transmit portion (transverter, power amplifier, etc.). The dish has been keeping me very busy all year!
Hoping to hear from you!
Randy Stegemeyer
P.O. Box 1590
Port Orchard, WA 98366 USA
Phone: 360-871-1111
FAX: 360-871-1700
E-mail: hamradio@oz.net
Created by Randy, W7HR
E-mail: hamradio@oz.net