This adapter board is for owners of a Hübner railbus in track 1 (Art. No. 4070 or 4071) thought. There, a LokSound 2 decoder was installed in the motor car on a special adapter, and in the control car a specially made light change decoder was installed. With the help of this adapter you can finally replace these old decoders with a modern LokSound 5 or LokPilot 5 Fx decoder. Insert a decoder with 21MTC snide into the adapter board and then install it in the railbus. Nothing needs to be rewired, all lamps will work correctly.
Note: Not suitable for the new edition of the railbus under Märklin® direction.