It is more striking than that because if you are starting with an SNR of 2-3 dB that buries your signal totally (i.e. a minus S4; meter don't bend in that direction). With V and H polarity you will never be more than -3 dB (half an S-unit) down.
Ed - KL7UW
At 06:50 AM 12/21/2007, Andrew Rich wrote:
Thats interesting about the affect of wrong polarisation - 20dB
According to my other info here that is about S4 to S7 difference.
Andrew Rich VK4TEC vk4tec@people.net.au mailto:vk4tec@people.net.au http://www.tech-software.net
-----Original Message----- From: Andrew Glasbrenner [mailto:glasbrenner@mindspring.com] Sent: Saturday, 22 December 2007 12:44 AM To: vk4tec@people.net.au; amsat-bb@amsat.org Subject: [SPAM] Re: [amsat-bb] Re: [SPAM] Re: AO51 Signals Importance: Low
AO-51 is LHCP on 435.150, RHCP on 435.300, and linear on 2401.200. If your helix is LHCP and you are listening to the .300 voice downlink, you are in the neighborhood of 20db down from a RHCP helix.
73, Drew KO4MA
----- Original Message ----- From: "Andrew Rich" vk4tec@people.net.au To: "Jeff Mock" jeff@mock.com; amsat-bb@amsat.org Sent: Friday, December 21, 2007 6:20 AM Subject: [amsat-bb] Re: [SPAM] Re: AO51 Signals
Does ao-51 have circular ?
I have LHCP on my antenna
--
Andrew Rich VK4TEC vk4tec@people.net.au mailto:vk4tec@people.net.au http://www.tech-software.net
-----Original Message----- From: Jeff Mock [mailto:jeff@mock.com] Sent: Friday, 21 December 2007 9:16 PM To: vk4tec@people.net.au; amsat-bb@amsat.org Subject: [SPAM] Re: [amsat-bb] AO51 Signals Importance: Low
The RG-213 loss should be less than 3dB if I remember correctly, I think you're okay there. Did you twist the helix the right direction?
jeff
Andrew Rich wrote:
Hello
I built a 10 turn helix for 435 MHz.
I have 15 meters of RG-213.
Radio is an ICOM 706 mkii G
I am not getting strong signals like I would have expected ?
Can someone share their setups and signal strengths ?
Maybe a pre-amp might help ?
Am I getting too much loss in the cable ?
--
Andrew Rich VK4TEC vk4tec@people.net.au http://www.tech-software.net
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa@hotmail.com ======================================