Receive NOAA Weather Satellite Images on a $20 Radio!
On September 20th 2013 I bought an EZCAP TV Dongle. Basically they are "to be used" as a way to receive
TV Broadcasts on your computer. Its a small device that plugs into your USB port of your computer. You
then connect either cable or an antenna to the other end of the device. At least that is the orginal purpose...
As far as receiving MilAir stuff goes these Dongles really aren't that great. They lack sensitivity and suffer
greatly from intermod and overloading. However with that limitation known you still can have some fun with
them and find signals that you may not normally find.
For years I've wanted to try to receive the NOAA weather satellite APT images (Automatic Picture Transmission) as
they are real-time weather satellites from several LEO (Low Earth Orbit) satellites. Currently NOAA 15, NOAA 18 and
NOAA 19 are still functioning. Their freqs are 137.6200 MHz, 137.9125 MHz and 137.1000 MHz respectively.
With a LEO satellite you will not be able to copy them 24/7, in most cases you'll get 10-15 minutes of good signal
from them depending on the orbital time for your location.
The antenna for this experiment was a simple discone in the attic. If I would take the time to build
a Quadrifilar Helix (QFH) Antenna for 137 MHz the picture quality would be much improved.
The software I am using is known as SDRSharp for controling the EZCAP TV Congle. Below is a screen shot
of SDRSharp while it was receiving NOAA 19. You can find more info about SDRSharp here:
Click Here. The software I'm using to process the NOAA images is WXtoIMG which can
be downloaded here: Click Here. Both pieces of software are FREE.
Second attempt. Below are the pictures I've captured from NOAA 18 during its 3:49 PM EDST (09/27/2013) pass over Florida.