IBM 1620 Manual page 70

2 T Th
4
D/B
Units
-5
1 T Th
4TT
T4D7 or
T4D15
Write T Th
Sam
Incr
De'cr
+54 Bit
Ten Thousand
01.55.49.1
1 T Th
Deer
1-
4 T Th
Switch
T Th
Bypass
T4D7 or
T4D15
4 T Th
(60 K Systems Only)
1 T Th
-5
1 T Th
Deer