Spectrogram of the switchoff of Muehlacker transmitter, made with "SpecLab"-Software.
The spectrogram was made by filming a laptop monitor.
<a href="//commons.wikimedia.org/w/index.php?title=User:Zonk43&amp;action=edit&amp;redlink=1" class="new" title="User:Zonk43 (page does not exist)">Zonk43</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>