The S-1403DL Mode S Accessory Unit (is an upgrade to the S-1403C) supports the new Mode S Data Link and ADS-B (extended DF17 squitter). The "DL" is backward compatible with the "C" model. Current ATE programs implemented on the S-1403C will operate with the S-1403DL without program changes.

The unit provides additional pulse code modulation, as specified by RTCA/DO-l81 to the ATC-1400A for testing Mode S Transponders. The Optional MLD (Multi-Level Diversity) function is available for testing Mode S Transponders with MLD requirements.

• Over 30 new screens, including support for MTL, Comm C and Comm D formats
• Remote Operation via IEEE 488.2-19887 or RS-232
• Continuous rotation "SLEW" control as an alternate to keypad data entry
• Rear panel interconnects for control and signal monitoring
• Control of P2, P3, P4 and P6 width, offset and amplitude
• Fixed frequency/fixed level RF output for diversity antenna testing
• Mode S interrogation up to 2500 PRF burst
• Onboard GPIB Interface to increase the speed of ATE test routines
• User-defined screens for user-specific tests
• PRF generator from 99.999 sec to 2500 Hz
• Flash memory for easy firmware upgrades
• Two Year Limited Warranty