| date | measurement | in use |
| 09jul04 | used sky and absorber
tracked blank sky |
cur values
installed 18jul04 valid from 14may04 |
| 15aug03 | used sky and absorber
tracked blank sky. |
installed 10oct03
valid from 15aug03 -13may04 |
| 20sep01 | used absorber and sky.
tracked blank sky. |
insalled 10oct01
valid data:01sep01 |
Notes: