Teletype Corporation Manuals
Teletype Corp Special Tools Manual
Info on HAL ST-6 Terminal Unit
Irv Hoff's Troubleshooting Notes for the HAL ST-6
HAL ST-6 Manual, PDF 200DPI, 8.7MB
HAL ST-6 Schematic Pages, PDF 400DPI, 1.8MB
Model 28 Reperf
Model 28 Reperforator Training Manual (Chapter 5), PDF, 9.5MB with thanks to James Tanton