MP00026 TR79-FA EngrDrws

This document is the "TR79-FA Field Maintenance Print Set" from Digital Equipment Corporation, copyrighted 1975. It provides comprehensive technical information for the TR79-FA Magtape Assembly and its interface to a PDP-11 system.

The print set includes a table of contents, drawing directories, and various technical diagrams and lists. Key sections detail electrical and mechanical aspects, covering:

• System Configuration: Wired assembly, module utilization, and Automatic Wire Tester (AWT) status for the TR79F.
• Functional Logic: Address selection, status and control registers, illegal commands, control functions, Magtape Transport (MTT) commands, gap timing, and motion control.
• Data Flow: MTT to TCU receivers, buffer control (including read-write buffer and parity generator), Direct Memory Access (DMA) control, Control Bus (CBUS) data, general bus data, and Tape Control Unit (TCU) to MTT drivers.
• Interconnections & Timing: MTT cables, UNIBUS connectors, MTT cable assembly, write timing, and a comprehensive wire list for the H7970E TCU to PDP-11 interface.
• Power Systems: Dedicated sections for the H720-E Power Supply and 861-C Power Control.