Exhibit 21 Subsidiaries of Dynatech Corporation Name of Parent or Subsidiary Organization* State or Other Jurisdiction - ------------------------ --------------------------- Dynatech Corporation (Parent)............... Massachusetts Dynatech LLC............ Delaware Airshow, Incorporated... Delaware DataViews Corporation... Massachusetts DaVinci Systems, Inc. .. Florida Industrial Computer Source................. California Itronix Corporation..... Washington Pacific Systems Corporation............ Washington Parallax Graphics, Inc. .................. Delaware Synergistic Solutions, Inc. .................. Georgia Tele-Path Instruments, Inc. .................. Delaware TTC International Holdings, Inc. ........ Delaware Dynatech Export Barbados, Incorporated........... West Indies TTC Belgium B.V.B.A. ... Belgium TTC Canada Ltd. ........ Canada Dynatech Corporation Ltd. .................. England Industrial Computer Source Europe.......... France TTC Telecommunications France SARL............ France Dynatech Gesellschaft Fur Datenveravbeitung, GmbH................... Germany TTC Federal Systems, Inc. .................. Delaware Dynatech Holdings Guernsey, Ltd. .................. Channel Islands Dynatech Investments, Guernsey, Ltd. .................. Channel Islands TTC Asia Pacific Limited................ Hong Kong DataViews Scandanavia A.B. .................. Sweden - -------- * Excludes nonmaterial subsidiaries.