Preparing radiosonde with Ground Check Device RI41 - RS41-SGP - RS41-SG

RS41-SG and RS41-SGP User Guide
Product status
Document code
M211667EN
Revision
J
ft:locale
en-US
Product
RS41-SGP
RS41-SG
Document type
User guide

In the sounding preparations, RI41 is connected to the sounding software computer with a USB cable and operated with the help of the sounding software. RI41 is switched on by connecting it to the sounding system and turning on the computer.

For information on configuring RI41 as the ground check option in the sounding software, see the applicable manual that also provides information on other options for preparing the radiosonde for the sounding.

Ground Check Device RI41
CAUTION

Do not touch the radiosonde sensors. They are fragile and can be easily contaminated.

WARNING! During humidity sensor reconditioning, the temperature of the sensor boom is about 150 °C for 3 minutes.

Follow the steps below to prepare the radiosonde for a sounding with RI41:

  1. Place the radiosonde on the ground check device carefully. Make sure that you place the radiosonde the back end (antenna end) of the radiosonde on the device first.
    CAUTION Make sure that the radiosonde sensor boom does not hit the support plate on the ground check device, as this may damage the sensor boom.

    The sounding software automatically detects the radiosonde and begins the sounding preparations.

  2. During the radiosonde preflight preparation phase, the sounding software performs several steps. These steps consist of ground check procedures for sensors, as well as optional features for setting the radiosonde inflight operation parameters, such as a timer for turning the radiosonde power off after a desired time, pressure, or altitude.

    In this phase, you can also set the radiosonde transmitter frequency or, alternatively, apply the station’s default frequency. Use the sounding software to modify the settings.

    The preflight procedure depends on the radiosonde and ground check device model.

    • RS41-SG with RI41:
      • T check: The radiosonde performs an built-in functional temperature check.
      • Reconditioning: Preparation of humidity sensor. Cooling after reconditioning
      • U check: The radiosonde performs a physical zero humidity check.
      • Updating radiosonde: The parameters and preparation results are updated to the radiosonde.
    • RS41-SGP with RI41 or RI41-B:
      • T check: The radiosonde performs an built-in functional temperature check.
      • Reconditioning: Preparation of humidity sensor.
      • Cooling after reconditioning
      • U check: The radiosonde performs a physical zero humidity check.
      • Stabilizing: Waiting for the pressure sensor to stabilize. Enter the pressure reference value from your own reference source or, with RI41-B, retrieve the pressure reference value automatically from the barometer module in RI41-B.
      • Ground check: Once the conditions have stabilized, that is, the PTU values are steady, ground check is performed.
      • Updating radiosonde: The parameters and preparation results are updated to the radiosonde.
  3. After the ground check is finished, the sounding software indicates the results with a message. Remove the radiosonde from the ground check device.

    Before the radiosonde is launched, you can return to the preparation phase anytime by placing the radiosonde on the ground check device again. The sounding software automatically returns to the ground check phase.

  4. If there is any delay in starting the sounding, for example, if you must wait before launching the sounding balloon, you can switch the radiosonde off by pressing the power switch. When you are ready to launch the balloon, switch the radiosonde back on.
Vaisala recommends releasing the radiosonde within 1 hour after the ground check. Keep the prepared radiosonde in office conditions (<60 %RH, free of contaminants, such as aerosols, glues, chemicals, and dust). If you cannot release the radiosonde within 1 hour, repeat the ground check.