The Märklin Magazine online archive contains PDF documents for downloading.
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Here you can download the sound library for the mDecoderTool. The sound library is expanded by Märklin at irregular intervals so that it is worthwhile to stop by again and again.
The two classic ways are again available for the update:
Connect the CS 3 to a router that is connected to the Internet using a LAN cable. Now switch on the CS 3. After a short time, the update will be displayed under System => CS 3 and you can start it there.
Download the file from our website with your PC and copy it to a USB stick. Please never try to open this file with your PC. Now insert the USB stick into one of the two USB sockets of your CS 3. Here, too, you can initiate the update within a short time under System => CS 3.