 |
2.4Ghz Sky mini-dish
How to modify a Sky mini-dish so it will work effectivly at 2.4Ghz.
|
Written by:
G4RFR (
FRARS )
|
Tuesday, 30 July 2002 |
 A simple but high gain antenna can easily be made from an old Sky mini-dish. The dish that we've used for this article is one from the southern UK region, and is around 35cm minor axis diameter.
A standard tin-can feed horn is used to feed the dish, and looking at the polar plot, we can see that very small side lobes exist, indicating good dish illumination.
The tin can feed detailed on the FRARS pages was used to feed the dish. The SWR adjustment screw in the feedhorn is used when the feed is mounted correctly on the dish feed arm, to optimise the SWR.
Dimensions
Measuring from the bottom of the dish, along the feed arm to the front of the tin can feed should be 243mm. Two feed arm supports are also made from 410mm long pieces of aluminium strip. The feedarms are secured to the tin-can feed by means of a couple of jubilee clips.
Take note of the angle of the existing LNB feed, and ensure that your new feed matches this. Looking along the top of the feed horn, you should aim to see about 1" above the top set of screws on the dish surface.
See the pictures below for further details of the construction.
A polar plot of the dish can also be seen below, showing just how good the front to back ratio is, along with the narrow beamwidth.
More FRARS Wireless LAN articles [Click here]2.4Ghz tin can feed [Click here]
| Attachments: (Click to view/download): |
Email author |
Link to this page | Print | Log In
|
 |
FRARS Features
|  |
 |
Getting Licensed
|  |
FRARS runs regular courses to help you prepare for your amateur radio licence.
For more information Click here
|
|
UK Microwave Group
| |
|
 In early 2004 the UK Microwave Group (UKuG) became the representative voice of the UK amateur radio microwave enthusiast after the RSGB disbanded its own Microwave
Committee.
Official website: Microwavers.org
|
|
