La description

Key Facts The R&S®SMW-B13T option is required if the R&S®SMW200A is to be equipped with a second RF path (R&S®SMW-B203 or R&S®SMW-B206). It provides the I/Q paths (e.g. D/A converters) to the I/Q modulators of both RF paths (A and B) of the R&S®SMW200A, as well as two pairs of (single-ended) analog I and Q outputs.
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