[Moon-net] 10GHz moon noise

[Chris Bartram]

Hello Charlie

> I am slowly getting 10 GHz setup, but I am so far
> getting less than ideal results. At best so far,  I have 0.95dB moon noise 
> and  11 dB sun noise (SFU=81 @ 10.7cm)....for a 3.7M dish I think I have a
> lot of improvement to make.

That's really good news! Like Brian, I have problems with minimum elevation, 
although in my case it's due to a dish mount which needs the attention of a 
welder! Having activity from VK once again might encourage me to bring it 
closer to the top of the 'to do' list...

> I have reverted to a linear feed to help with optimisation.  My initial TX
> testing proved disappointing as I had 25 W at the feed but was unable to
> detect/ hear any echoes  with moon at Apogee and 0.8dB moon noise.

> I have read that the amount of moon noise changes with the "phase of the
> moon"..........Is this correct?..........If  so what levels of variation
> exist?

It sounds like it may be worth paying attention to the feed as well as the 
preamp. Moving from a 1.8WL aperture W2IMU horn to a a more modern dual-mode 
design brought me about 2dB improvement in Sun Noise, but then I have an f/D 
of 0.935, which is unusual.

You should hear echoes at perigee, and you'll certainly be able to make QSOs 
with the current set-up. Don't forget the doppler correction, and remember 
you will be listening for 'modulated noise' rather than a tone. With my 2.4m 
offset dish and 35 - 40W I can hear CW echoes at any time, and occasionally 
_just_ copy my ssb echoes at perigee. I see about 1.3 -1.4dB Moon Noise at 
perigee, and about 0.2dB less at apogee. My system currently uses a coax 
relay. I'm changing to a WG switch which should improve Moon noise by another 
0.5dB or so.

Vy 73

Chris
GW4DGU