DEC-00-HRS64-E-D RS64 disk file maintenance manual

This document is a maintenance manual for the Digital Equipment Corporation (DEC) RS64 Disk File (PDP11/20), with editions published between 1971 and 1973.

The manual provides comprehensive instructions for interfacing, installing, operating, and maintaining the RS64 Disk File. Key information includes:

• Product Overview: Describes the RS64 as a fast, random-access disk file offering up to 1,280,000 bits of storage (expandable to over 5 million bits with multiple units). It is a 19-inch rack-mountable unit, featuring a 10-inch nickel-cobalt plated disk, 32 fixed read/write heads, a self-synchronizing clock recovery system, and write protection. It operates on either 115V or 230V.
• Installation & Operation: Details unpacking, mechanical installation (rack mounting), power and signal connections, system checkout, and procedures for moving/shipping the unit. Operational instructions cover disk unit assignment (0-3 or off-line) and setting track-specific write lockout.
• Theory of Operation: Explains the internal workings, including system relationships with a controller, disk surface and track arrangements (using timing tracks A, B, and C for clocking, address/data markers, and block addresses), and functional descriptions of the data and timing paths. It covers read/write electronics (e.g., read amplifiers, disk writers, series switches, phase-locked clock) and specific module descriptions.
• Interfacing: Outlines bus voltage spectrum, bus philosophy, and a detailed list of interface signals (e.g., disk select, track select, write enable, read data, clock strobes, address marks) and their assertion levels and usage. It also specifies format requirements like NRZI recording, disk speed, and synchronizing logic for read and write operations.
• Maintenance: Provides guidance on preventive maintenance (cleaning, inspection), corrective maintenance (module/pin designation, power supply adjustments, read amplifier-peak detector adjustments, rewriting timing tracks), and detailed troubleshooting for track address, sector address, timing, and data errors. It also includes procedures for disk assembly removal/replacement and a list of recommended spare parts.

The manual is intended for maintenance personnel with a basic understanding of disk files.