The D400 unit is a complete in-service T1 test set. It's full-duplex, drop and insert capabilities allow simultaneous channel testing in both directions. The two channel tone synthesizers and receivers provide noise and frequency measurements from 0 to 3990Hz. Bit patterns can be sent and displayed in both directions simultaneously. The A/B/C/D signaling bits of all 24 channels can be scanned and displayed on the screen. Loop timing and frame slip counting is performed. Plus all the performance monitoring features are included so tariffed service requirements can be checked and verified.

OPTIONS:
D401: Bert option
D402: Signaling option

FEATURES:

• In-service channel access
• Sending and measuring tones
• A B C D signaling bit scan
• Slip counting and line frequency
• Monitoring of voice or test tones
• Measurement of PCM offset
• Sending and receiving channel codes
• CSU Loopback NI Loopback Smart Repeater Loopback

Complete specifications available upon request."