RD52-D, -R Fixed Disk Drive Subsystem Owner's Manual

This Owner's Manual provides comprehensive guidance for the RD52-D (desktop) and RD52-R (rack mount) Fixed Disk Drive Subsystem from Digital Equipment Corporation.

Purpose: These free-standing units function as add-on fixed disk drives for MicroPDP-11, MicroVAX, PDP-11/23 PLUS, and other Q-Bus systems.

Key Features:

• Storage Capacity: Each subsystem offers 31 Mbytes of storage on four non-removable disks.
• Components: It comprises a fixed disk drive, its own power supply, a DC cooling fan, and a printed circuit board, all housed within a mounting chassis.
• Compatibility: The subsystem operates with the RQDX1 (M8639) RD/RX controller module (and optionally an RQDX1-E extender) installed in the host computer, supporting the Digital Storage Architecture (DSA) Mass Storage Control Protocol (MSCP).
• Configurability: It can be set up in single or multiple drive configurations, with specific I/O cable connections (J1, J2, J3) and logical unit number (LUN) assignments (Disk Unit Numbers or DUNs are automatically assigned by software). The RQDX1 controller module specifically supports up to two fixed disk drives.

Installation & Operation:

• Site Requirements: Emphasizes crucial environmental considerations, such as allowing for air circulation and keeping the unit away from heat sources, magnetic fields, and excessive dust or static.
• Power: Users must correctly identify their power cord and check the voltage switch (115V or 240V) to avoid damage.
• Critical Setup - Formatting: Before initial use, the RD52 subsystem must be formatted, a process that destroys all existing data on the disk. The manual details distinct formatting procedures for MicroPDP-11 and MicroVAX systems, including various modes (Reformat, Restore, Reconstruct) depending on bad block information.
• Controls: The front panel features an On/Off switch, a Ready button (with a green LED indicating readiness), and a Write-Protect button (with a yellow LED indicating protection, preventing data writes). The rear panel includes various connectors, the voltage select switch, a circuit breaker, and a fan exhaust.
• Care: Advises against dropping or bumping the drive, recommends regular file backups, and emphasizes using the write-protect feature during backup or testing to prevent accidental data loss.

Maintenance & Troubleshooting:

• Professional Service: The document strongly states that major repairs or replacements should only be carried out by qualified field service personnel.
• Data Backup: A critical warning is issued to back up all files on the fixed disk before attempting any repair or replacement procedures.
• Field Replaceable Units (FRUs): It lists common FRUs (e.g., cables, disk drive, main printed circuit board, power supply, fan) and provides step-by-step removal and installation procedures for these components.
• Diagnostics: Troubleshooting typically involves running system diagnostic tests or the User Test.

Appendices: Provide detailed system specifications (environmental, physical dimensions, performance metrics like access time and transfer rate), comprehensive connector pin numbers and signals, logical unit number designation tables, a list of related documentation, and information on various service options offered by Digital Equipment Corporation.