64
•
Check the power source of the transmitter, the status of the transmitter unit (see
“power” LED) and the current through the LED (via current adjust knob and BNC
socket). For further information see the
LAS
instruction manual.
•
Check the power source of the receiver and the status of the receiver unit (see
“power” LED). Perform a calibration check of the electronics. For further information
see the
LAS
instruction manual.
•
Check the windows of both the transmitter and receiver unit. Dust, water droplets and
icing on the windows lead to signal attenuation. Regularly clean the windows and if
necessary turn the window heater on.
•
Check the transmitter and receiver units for water leakage and internal condensation
on the lenses and windows, as this can also lead to signal attenuation (and even
corrosions of the electronics!). Although the housing of the both the transmitter and
receiver unit are sealed with O-rings (plus silicagel packages and RH-indicator),
improper closure of the back panel and a loose cable plug can lead to water leakage
and as a result to internal condensation problems. If necessary replace the silicagel
packages by new ones (see RH-indicator on rear window). See
LAS
manual for
further information.
•
The alignment of the
LAS
(for further instructions see section 3.7 of the
LAS
/
XLAS
instruction manual). An unstable mounting construction for the
LAS
can regularly lead
to a misalignment of the
LAS
.
c) The display shows
realistic values
:
This indicates that the
LAS
is working fine. Check if the signal strength (= Demod or U
demod
) is
stable and similar to the value when the LAS was installed and optically aligned. In theory the
signal strength should be stable. Except during conditions of rain, fog, or low visibility the
signal can drop to zero. In case the visibility conditions are good but the signal strength has
dropped significantly, check the following:
•
Check the windows of both the transmitter and receiver unit. Dust, water droplets and
icing on the windows lead to signal attenuation. Regularly clean the windows and if
necessary switch the window heater on.
•
Check the transmitter and receiver units for water leakage and internal condensation
on the lenses and windows, as this can also lead to signal attenuation (and even
corrosions of the electronics). Although the housing of the both the transmitter and
receiver unit are sealed with O-rings (plus silicagel packages and RH-indicator),
improper closure of the back panel and a loose cable plug can lead to water leakage
and as a result to internal condensation. If necessary replace the silicagel packages
by new ones (see RH-indicator on rear window). See
LAS
manual for further
information.
•
The alignment of the LAS (for further instructions see section 3.7 of the
LAS
/
XLAS
instruction manual). An unstable mounting construction for the
LAS
can regularly lead
to a misalignment of the
LAS
.
Summary of Contents for LAS
Page 1: ...Instruction Manual Large Aperture Scintillometer LAS...
Page 28: ...27 Figure 17 Operational weather station of LAS RET system...
Page 29: ...28...
Page 39: ...38...
Page 45: ...44...
Page 49: ...48...
Page 51: ...50 Figure 33 Configuration screen and default settings of supplied RF modems...
Page 55: ...54...
Page 69: ...68...
Page 71: ...70 APPENDIX 9 CONNECTION PLAN LAS BET LAS RET Figure 47 Connection plan LAS BET system...
Page 72: ...71...
Page 73: ...72 Figure 48 Connection plan weather station LAS RET system...
Page 74: ...73 Figure 49 Connection plan scintillometer LAS RET system...
