The HP 3787B digital data test set is a bit error rate tester (BERT) designed for use on T1 leased, Digital Data System (DDS), 56 kbit/s switched and Packet Switched services transmission line and multiplexing equipment.
The 3787B has a comprehensive range of in-service features (for example, Frame, CRC, BPV and jitter analysis, alarm monitoring, internal printer for data logging), which maximizes circuit availability by detecting circuit deteriorations and intermittents, before they seriously affect the service.
The 3787B also provides comprehensive out-of-service features (for example, logic (binary) test patterns and full range of T1/DDS loopback codes), which are used to provide qualitative results for circuit troubleshooting and end-to-end test results that relate to actual in-service performance.
The 3787B combines three test sets in one: DS1/1C testers, DDS testers, and DS1 channel access equipment. It also includes a built-in printer, many methods for presenting the error information (for example, Count, BER, ES, and EFS) and error analysis (for example, % Availability, % EFS, % Severely Errored Seconds).
For the development or maintenance of DMI (Digital Multiplexed Interface) and Signaling Systems No 7, you can connect a protocol analyzer to the 3787B and substitute the BER test pattern with one from the protocol analyzer.
Measurement capability of the HP3787B:
- Operating frequency: DS0 (64 kbit/s). DS1 (1.544 Mbit/s), DS1C (3.152 Mbit/s)
- Framing: DS1 (SF, ESF, T1DM, and Ft only), DS1C, and DS0B
- Line code: B8ZS, AMI
- Error types: Logic (Binary), Bipolar Violations, Frame Word, CRC-6 Word
- Error results: Error Count, Error Ratio, Error Seconds, Error Free Seconds, % Error Free Seconds
- Error analysis: % Availability, % Unavailability, % Severely Errored Seconds, % Error Seconds, % Degraded Minutes, Count Consecutive SES, Count SES, Count ES, Count Deg Min
- Alarm seconds: Instrument Power Loss Seconds, Signal Loss Seconds, AIS Seconds, Frame Loss Seconds, Test Pattern Loss Seconds
- Frame slips (controlled): Duplicated frames are indicated as positive frame slips. Deleted frames are indicated as negative frame slips
- Protocol analyzer interface: RS-232-C 4-wire synchronous interface. When interfacing at DS1 or DS0, the following channels can be accessed: DDS primary and secondary channels, ISDN "B" or "D" channels (64/56 kbit/s), ESF datalink or D4 Fs channel
- DS1/DS1C signal voltage: Positive and negative peak voltage displayed
- DS0 bit monitor: Selected received customer bytes displayed
- Signalling bits: A,B (SF) or A,B,C,D (ESF) signalling bits can be set and displayed when 56 kbit/s circuit switched is selected