
Grupa: Użytkownik
Lokalizacja: Praha JO70FD
Posty: 118 #2163414 Od: 2013-1-22
| It is an evolution of the OM6AA feed. Just recalculating it into 70cm band. However without link to author. But he is not the first one.. No surprise at all.
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
The idea has been taken from DL4MEA feed
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
, redesigned for our eliptic dish
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
. When we asked Rasto OM6AA for optimalization
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
for such eliptic dish
TYLKO ZAREJESTROWANI I ZALOGOWANI UŻYTKOWNICY WIDZĄ LINKI » DARMOWA REJESTRACJA
, he found, that the dish has not enough performance of the back radiation. One way to improve it was enlarge size of the reflector. However larger reflector will more screen our relatively small dish. Finaly we got an idea use the bigger reflector but the edge part of reflector bend back around the loop (to pack it, hi). OM6AA optimized this design by his mathematic tools and verify it in non reflection chamber of Prague technical university. The result has been publish, beside other as well as in DUBUS. Later on this feed (designed for terrestrial aplication, not for EME, because it radiate linear polarization only, not circular one) has been recalculated for 70cm by OK1DFC. Of course, I can not exclude, that the XE1XA had exactly the same idea, but, frankly, it is not very likely, isn't it? But I don't want create any contraversy. Take these info as you want. The most important is, if it will bring you the satisfaction in 70cm operation. 73 by OK1VPZ |