IBM RT Series Hardware Reference Manual page 21

Weight
8.5 Kg (18.74 pounds)
Power Cable
Length 2.5 m (8.25 ft.)
Signal Cable
Length 2.5 m (8.25 ft.)
Connector Specifications
Pin
Function
1 Signal ground for vertical sync
2 Vertical sync
3 Signal ground
4 Reserved
5 Signal ground
6 Reserved
7 Signal ground for video
8 Video
9 Signal ground
10
Reserved
11
Signal ground
12
Reserved
13
Signal ground
14 Reserved
15
Signal ground for horizontal sync
16
Horizontal sync
Advanced Monochrome Graphics Display 3