Currently there are 4 NOAA APT weather satellites in operation the
latest being NOAA 19 launched on the 6th February 2009. NOAA 17 developed a serious fault in February 2010.
This fault results in badly degraded images which then impact composites built using them. For this reason I
took the decision to cease recording of NOAA 17 images entirely however release 2.10.7 of WXtoImg provided the option
of excluding specific satellites from composite images so this option is now used instead.
From May 8 2010 most NOAA 17 passes poduce good images with only the occasional poor one. The NOAA POES status page should carry the latest information.
All the satellites are in approximately circular polar orbits at around 850km altitude
and transmit 10w RF in the 137-138MHz band which makes them relatively easy to receive with a simple antenna.
That said the current turnstile antenna is performing badly at elevations below 20 degreees and will eventually be supplemented or replaced with another QHA.
The main problem with reception in the UK is the staggeringly stupid decision to allow text pagers to operate in the same band. Pager interference will
be seen on most of the pictures as short dark lines where a pager signal wiped out the satellite.
The MCIR-precip composite images give a good idea of where there is likely to be rain by use of bright false colouring.
Looking at two images recorded a few hours apart can usually show the probable path the rain will follow. Note though that the
colours are only an indication of possible rain not that rain is actually reaching the ground.
Pager tower causing the interference bars This tower is less than a mile away and operates just 60Khz above the nearest satellite frequency - avoiding the interference is impossible.
