Vaisala RS92-KL User Manual
Page 27
Chapter 3 ________________________________________________________________ Operation
VAISALA_______________________________________________________________________ 25
3.
Switch on the PC and start a new sounding with the DigiCORA®
sounding software. For detailed instructions on using the software,
refer to the DigiCORA® User’s Guide.
4.
Switch on the Ground Check Set by pressing the power switch. The
green LED in the power switch is lit.
5.
If needed, tune the radiosonde frequency.
The radiosonde is tuned at the factory to the default frequency of
403 MHz. You can adjust it within the 400.15 to 406 MHz band
with the tuning potentiometer provided with the Ground Check Set
GC25. The hole for frequency tuning, covered by tape, is located
in the upper left corner of the radiosonde.
-
Partially detach the tape so that only the frequency tuning hole
is revealed. Leave the other end of the tape attached to the
radiosonde.
-
Wait until the sounding software is in Track mode (display
shows 40x.xx Hz Trck...).
-
Turn the tuning screw clockwise with the potentiometer to
lower the frequency and counterclockwise to increase the
frequency. Adjust the frequency carefully, staying between
400.4 ... 405.6 MHz. These limits ensure that the transmitter
does not drift outside the available band of 400.15 ... 406
MHz. You can see the frequency changing in the sounding
software when you turn the screw.
-
Re-attach the tape to cover the tuning hole. The tuning hole
has to be covered during sounding to prevent water from
penetrating into the radiosonde electronics.
6.
The DigiCORA® sounding software goes through reconditioning,
timer setting, and ground checking. Set the timer when the ground
equipment prompts for it. Add an average of 30 minutes to the
targeted sounding or transmission time.
NOTE
The tuning potentiometer has to be a ceramic Phillips head trimmer. It
is included in the Ground Check Set delivery. If you do not have a
proper tuning potentiometer, you can order it from Vaisala (order code
214513).