This 12GHz system was built as an educational program to detect microwave
thermal radiation from the Sun, the cold sky, the ground, the human body,and
Examples on what can be done with a similar system is described by William Lonc in Classroom Radio Telescope.
It is very easy to implement such a system: The receiving equipment is a 83 cm offset dish with LNB connected via a short coax cable to a satellite finder that replaces the receiver.
The LNB has a Noise Figure of 0.7dB, it receives from 12.50 GHz to 12.75 GHz, the output is from 950 MHz to 1750 MHz and feeds the satellite finder (Satfinder).
The Satfinder is normally used to set the dish towards a satellite when installing an equipment for the reception of satellite television. It is a very small box with an analogic meter that shows the intensity of the signal, the gain is varied via a potentiometer.
The built-in analog meter has ten graduation marks, when the dish is pointed to the Sun the meter shows a sharp peak.
The satellite finder was modified as follows: A shielded two-leads cable was soldered to the meter terminals and the other end of the cable is connected a A-to-D converter.
The output of the satfinder goes normally, via a coax, to the receiver and the receiver powers the satfinder and the LNB with 13/18 Volt through the coax.
In our case a 15 volt regulated power supply is connected directly to the output.
The data from the A-to-D converter are then processed by the Radio-Sky Pipe software.
This is the Satfinder , protected by a polystirene container, on the left is the coax cable to the LNB, on the right is the output F-plug connected to the power supply,and barely visible, the cable to the A-to-D converter.
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