<s>
Fast	B-Device
Simple	I-Device
QSO	I-Device
(	O
FSQ	O
)	O
is	O
an	O
amateur	O
radio	O
digital	O
differential	O
frequency	O
modulation	O
mode	O
developed	O
by	O
Con	O
Wassilieff	O
ZL2AFP	O
with	O
Murray	O
Greenman	O
ZL1BPU	O
in	O
2015	O
.	O
</s>
<s>
FSQ	O
is	O
used	O
primarily	O
on	O
HF	B-Algorithm
on	O
fixed	O
frequency	O
channels	O
.	O
</s>
<s>
FSQ	O
uses	O
incremental	B-Device
frequency	I-Device
keying	I-Device
(	O
IFK+	B-Device
)	O
and	O
has	O
efficient	O
alphabet	O
encoding	O
as	O
well	O
as	O
no	O
need	O
for	O
syncing	O
to	O
receive	O
.	O
</s>
<s>
The	O
ITU	B-Device
emission	I-Device
designator	I-Device
is	O
300HF1B	O
.	O
</s>
<s>
The	O
modulation	O
is	O
constant	O
amplitude	O
,	O
phase	O
coherent	O
multiple	B-Device
frequency	I-Device
shift	I-Device
keying	I-Device
(	O
MFSK	B-Device
)	O
,	O
using	O
IFK+	B-Device
coding	O
with	O
32	O
frequency	O
differences	O
,	O
yielding	O
32	O
unique	O
codes	O
.	O
</s>
