The unwinder must be attached firmly, so
that it is not able to twist freely, or the suspension string may unwind at too high a speed
and the radiosonde hit the ground during the launch. The unwinder must be able to swing
slightly during the sounding. Follow the steps and figures below to attach and align the
unwinder correctly when it is attached directly to the balloon.
Pass the unwinder hook through the loop created by the tied balloon neck.
Make sure that the hook comes out the other side, as shown in the
following figure.
The unwinder is now firmly attached to
the balloon.
Align the unwinder so that it points directly downwards from the balloon neck, as shown
in the figure below.
CAUTION To ensure a
successful sounding, align the unwinder so that it points downwards from the balloon
neck.