----- Original Message ----- From: "Andrew Rich" [email protected] To: "OZ1MY" [email protected]; "[email protected] Org" [email protected] Sent: Tuesday, January 01, 2008 4:54 PM Subject: [amsat-bb] Re: 70cm Yagi and AO-51
If I have this correct.
- LHCP recieved on a RHCP can knock your signal down by some 20dB
- LHCP matched with LHCP will result in a good signal.
So how does a linear antenna equate when receiving a circular signal ?
And the other way around, a circular receiving a linear signal ?
Andrew Rich VK4TEC
Hi Andrew, VK4TEC
Read please my article "Switching four Polarizations on a 70 cm Crossed Yagi"
Part-1 in AMSAT-Journal March/April 2007 Part-2 in AMSAT-Journal May/June 2007
Switching from Horizontal to Vertical and from RHCP to LHCP from the shak using 4 small coax relays antenna mounted you will get the better polarization match between the signal actually received from the satellite and your antenna system. In addition mounting the elements in X configuration over the boom you get Horizontal and Vertical polarizations for best performance in tropo communications.
If you cannot find the above articles please let me know.