Siemens S30813-Q298-X1 EWSD (Elektronisches Waehlsystem Digital) digital switching system Telecom System Card / Module

The Siemens S30813-Q298-X1 is a genuine STM-1 optical interface board from the Siemens EWSD (Elektronisches Waehlsystem Digital) digital switching platform, carrying the internal Siemens designation STM1:O(W) (STM1:O), indicating an STM-1 (155 Mbit/s) optical transmission interface card. EWSD is Siemens’ large-scale digital circuit-switching system for fixed-line telephone exchanges, deployed extensively worldwide from the 1980s through the 2000s and still supporting many legacy and developing-market networks today. This board is confirmed via multiple telecom-parts reseller catalogues as belonging to the S30813-Q series of EWSD subrack cards used for SDH/optical interconnection between exchange racks; the precise sub-variant distinction is not independently documented beyond the platform and interface-type identification, so we state these with confidence and flag any finer detail as unconfirmed rather than guess. It is supplied as a genuine pull, tested where possible, and intended as a like-for-like spare for engineers maintaining or expanding an existing EWSD installation. Tech-Star (UK-based, shipped worldwide) stocks a wide range of legacy Siemens EWSD boards; get in touch to confirm stock and fit for your exchange configuration.