[Moon-net] [Moon] Chapperal Septum Feed

[OK1DFC]

It is necessary to continuous and you will say WHOWWWW very soon :-))) 
GL and see you soon via Moon. 
Zdenek OK1DFC 

------------ Původní zpráva ------------ 
Od: Koellner, Guenter (NSN - DE/Muenich) <guenter.koellner at nsn.com> 
Předmět: [Moon] Chapperal Septum Feed 
Datum: 25.10.2007 20:41:04 
---------------------------------------- 
Hello, 

since my dish having a f/D=0.32 is a very deep one, I now made a chapperal ring. 
Based on W1GHZ's advice, it is three times 0.17WL distance and 0.3WL deep. 
The back plate is massive from 1mm alu with a formed 1cm wide flange for the 
feed's tube. 
The rings are made from 1mm thick stitched material, which was easier to bend 
and also already provided one side of the drills. 
The rings are bent 90°. I used simple standard rivet every 3rd hole. It needed 
to evenings of hammering. 

I cannot tell a WHOW!, testing with the driver only showed that the echos 
strength became better but definitly more continuous. 

You can see pictures on my web page: 
http://www.qsl.net/dl4mea/antennas/feed/chapp23a.jpg and 
http://www.qsl.net/dl4mea/antennas/feed/chapp23b.jpg 

73, Günter, DL4MEA 





Zdenek - OK1DFC 
www.ok1dfc.com 
QRV 144 - 1296 MHz EME 
QRO and 10m DISH 
WAC 432 - 1296 MHz