<s>
The	O
AN/APS	B-Algorithm
-4	I-Algorithm
,	O
originally	O
known	O
as	O
ASH	O
(	O
air-surface	O
,	O
model	O
H	O
)	O
is	O
an	O
early	O
military	O
air	B-Device
to	I-Device
air	I-Device
and	O
air	B-Algorithm
to	I-Algorithm
surface	I-Algorithm
radar	B-Application
used	O
by	O
American	O
and	O
British	O
warplanes	O
during	O
World	O
War	O
II	O
.	O
</s>
<s>
APS-4	B-Algorithm
operated	O
in	O
the	O
X	B-Algorithm
band	I-Algorithm
at	O
3cm	O
,	O
compared	O
to	O
the	O
10cm	O
S	B-Algorithm
band	I-Algorithm
used	O
by	O
most	O
radars	B-Application
of	O
the	O
era	O
.	O
</s>
<s>
In	O
Fleet	O
Air	O
Arm	O
and	O
RAF	O
service	O
it	O
was	O
known	O
as	O
ASV	B-Algorithm
Mark	I-Algorithm
IX	I-Algorithm
and	O
equipped	O
a	O
number	O
of	O
aircraft	O
including	O
the	O
Fairey	O
Firefly	O
,	O
Fairey	O
Barracuda	O
,	O
de	O
Havilland	O
Mosquito	O
and	O
a	O
small	O
number	O
of	O
Grumman	O
Avengers	O
.	O
</s>
<s>
The	O
APS-4	B-Algorithm
radar	B-Application
is	O
a	O
lightweight	O
air-to-air	O
and	O
air-to-surface	O
radar	B-Application
with	O
a	O
detection	O
range	O
for	O
large	O
ships	O
of	O
about	O
,	O
and	O
about	O
against	O
aircraft	O
.	O
</s>
<s>
Physically	O
,	O
the	O
APS-4	B-Algorithm
consists	O
of	O
a	O
control	O
box	O
,	O
one	O
or	O
two	O
indicators	O
,	O
the	O
same	O
number	O
of	O
indicator-amplifiers	O
,	O
an	O
antenna	O
,	O
a	O
transmitter-receiver	O
,	O
and	O
a	O
cable	O
junction	O
box	O
.	O
</s>
<s>
The	O
radar	B-Application
weighed	O
.	O
</s>
<s>
The	O
APS-4	B-Algorithm
broadcast	O
in	O
the	O
X-band	B-Algorithm
with	O
a	O
wavelength	O
of	O
3cm	O
.	O
</s>
<s>
Peak	O
broadcast	O
power	O
varied	O
from	O
40	O
to	O
70kW	O
according	O
to	O
radar	B-Application
version	O
.	O
</s>
<s>
The	O
APS-4	B-Algorithm
emitted	O
a	O
radio	O
beam	O
in	O
the	O
form	O
of	O
a	O
6°	O
cone	O
.	O
</s>
<s>
In	O
search	O
mode	O
,	O
the	O
radar	B-Application
beam	O
scans	O
through	O
150°	O
in	O
azimuth	O
,	O
and	O
while	O
doing	O
so	O
would	O
run	O
two	O
lines	O
scans	O
,	O
each	O
separated	O
by	O
4°	O
.	O
</s>
