Jan Lustrup wrote:

Well first of all I'm not om 1.3GHz but 12GHz.

Oh. That makes a very big difference.
Explains why the sun was only 10x brighter too.

At that frequency after the sun and the moon you need at least three
more orders of magnitude sensitivity before the next brightest objects
Crab, CassA Orion nebula and Jupiter.

Most of the bright radio sources lose power output as frequency^(-0.6)
or worse. So you have a better chance at lower frequencies.

I think you system noise floor with that antenna may be above the limits
of detection for other objects at any frequency. Is your email address
valid I can send you a scan a of suitable (very old) graph of the
brightest radio sources in the sky and their frequency

Regards,
Martin Brown

(my unlikely looking email address is valid unmodified)

The sun brings appz 8 to 9dB of noise over quite sky, and the moon from 0.5
to 0.8dB of noise also compaired to quitesky.
I think sun noise is less on 12GHz the 1.3GHz, so thats why it is so low.
I've tried Taurus A and Virgo A and am not sure if it is noise/temp-drift
but there might be somthing there. I will try to make drift compsation to be
sure. Thats why I would loike to know if it is at all possible with this
smale antenna on 12GHz.
Jan



"Martin Brown" skrev i melding
...
Jan Lustrup wrote:
I have a 1.2 meter offset sat dish and a 0.2dB LNB head.
So far all i get is the sun (at +9dB) and the moon (at +0.7dB). These
mesuarments are refered to quite sky.
Ground noise is 5dB.
Can I expect to get anything else? Or must I get a larger antenna?

The moon noise can be seen he http://home.no.net/jhhl/egne/moon.pdf
If I have read the page right and you are getting a lunar signal at 1.3GHz
then there is a sporting chance you will also detect Cass A which I think
is about the same brightness, slightly fainter are Cygnus A, Crab Nebula
and Orion Nebula. SARA may have some guidance on this.

YOu should also see the galactic centre.

What is a bit puzzling is that the sun isn't brighter. I'd have expected
it to be aprrox 100x (20dB) stronger than the moon. AGC somewhere?

Regards,
Martin Brown
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