Sound Decoder SD21A for SX1, SX2, DCC and MM

Doehler & Haass SD21A – Sound  Decoder for 21 MTC Interface

The SD21A Gen 2 is a sound and function decoder designed for locomotives with a 21 MTC socket (NEM 660) and supports digital operation with SX1, SX2, DCC and MM as well as analog driving. It offers high performance: up to 2 A load capacity, 8 independent sound channels, 128 Mbit memory for sound projects and firmware updatable via the SUSI interface.
Two variants exist: the SD21A-4 with amplified outputs (AUX3–6 up to 1 A) and the SD21A-5 with logic-level outputs (AUX3–6 at 3.3 V).