HP / Agilent 70842B 3 Gb/s Error Detector Module

The HP/Agilent 70842B is a 3 Gb/s error detector module designed for high-speed digital testing within modular mainframe systems. It compares incoming data against internally generated reference patterns to detect and quantify bit errors across frequencies from 100 Mbit/s to 3 Gbit/s. The module supports PRBS, zero substitution/variable mark density patterns, and word test patterns as specified by an external pattern generator such as the HP 70841B. The 70842B performs comprehensive error metrics including error count, delta error count, error ratio, delta error ratio, and errored/error-free intervals at second, decisecond, centisecond, and millisecond resolutions. It derives CCITT Rec G.821 compliance measurements: %Unavailability, %Availability, %Errored Seconds, %Severely Errored Seconds, %Degraded Minutes, and Power-loss Seconds. Transition-based measurements (0→1 and 1→0 error counts and ratios) enable detailed error pattern analysis.

Technical Specifications

Operating Frequency Range: 100 Mbit/s to 3 Gbit/s

Supported Test Patterns: PRBS, zero substitution/variable mark density, word test patterns

Module Slot: 418 MMS

I/O Ports: Five

Clock: Real-time with battery backup for event logging

Key Features

Flexible gating modes: Manual (Run/Stop control), Single (user-initiated periods), Repeat (continuous cycling)

Measurement period definition by time (1 second to 99 days), error count (10, 100, or 1000), or bit count (1E7 to 1E15)

Automatic or manual pattern synchronization with selectable sync gain/loss thresholds

Front-panel status indicators: Gating, Clock Loss, Data Loss, and Sync Loss LEDs

External printer logging via HP-IB

Typical Applications High-speed serial data validation, telecommunications compliance testing, and error performance characterization in digital communication systems.

Compatibility & Integration Designed for integration into HP/Agilent 70001A and 70004A mainframe systems. Operates in conjunction with pattern generator modules such as the HP 70841B.