EXFO FTB-500 (Window XP) - Manual (Page 366)

Data Types
358 FTB-500
Applicable Data Types for Input—IEEE 488.2

This data type will be used for integer representation in hexadecimal
(base 16), octal (base 8) or binary (base 2). The numeric
representations will begin with “#H” for hexadecimal, “#Q” for octal
and “#B” for binary.
Examples: #Hf3bc015d, #h01a4, #hfe
# H/h C/c
B/b
A/a
D/d
E/e
F/f