digital tandem造句

Starting with two Digital Tandem Switch ( DTS ) voice-switching systems designed specifically for them by the Collins Radio Company of Cedar Rapids, Iowa ( later a division of Rockwell International ), MCI began offering competitive circuit-switched direct-dial services using a combination of their own microwave circuits and leased circuits from AT & T made available to them from the landmark Carterfone decision.
It's difficult to find digital tandem in a sentence. 用digital tandem造句挺难的