About the only info I've been able to scare up is from the Group for Earth Observation in the UK. This is the info they have but don't know how old it is:

Current NOAA series – APT (analogue) 137 MHz band, HRPT (digital) 1.69 GHz band.
  • NOAA 15 AM Secondary - APT on 137.620 MHz (good) ; HRPT 1702.5 MHz (weak)
  • NOAA 16 PM Secondary - HRPT 1698 MHz (good)
  • NOAA 17 AM Backup - No Images
  • NOAA 18 PM Secondary. Launched 20th May 2005 and is using 137.9125 MHz for APT downlink. HRPT 1707 MHz (good).
  • NOAA 19 PM Primary. Launched 6th February 2009 and is using 137.100 MHz for APT downlink. HRPT 1698 MHz (good).

That's from: http://www.geo-web.org.uk/sat_future.php

And that's why I thought that perhaps the birds were still flying and operational.