<s>
The	O
15-meter	B-Algorithm
band	I-Algorithm
(	O
also	O
called	O
the	O
21-MHz	O
band	O
or	O
15	B-Algorithm
meters	I-Algorithm
)	O
is	O
an	O
amateur	O
radio	O
frequency	O
band	O
spanning	O
the	O
shortwave	O
spectrum	O
from	O
21	O
to	O
21.45MHz	O
.	O
</s>
<s>
The	O
15-meter	O
wavelength	O
is	O
harmonically	O
related	O
to	O
that	O
of	O
the	O
40-meter	B-Algorithm
band	I-Algorithm
,	O
so	O
it	O
is	O
often	O
possible	O
to	O
use	O
an	O
antenna	O
designed	O
for	O
40	B-Algorithm
meters	I-Algorithm
.	O
</s>
<s>
The	O
15-meter	B-Algorithm
band	I-Algorithm
was	O
designated	O
by	O
the	O
1947	O
International	O
Radio	O
Conference	O
of	O
Atlantic	O
City	O
in	O
part	O
to	O
compensate	O
for	O
the	O
loss	O
of	O
the	O
160-meter	O
band	O
to	O
amateurs	O
by	O
the	O
introduction	O
of	O
LORAN	O
during	O
World	O
War	O
II	O
.	O
</s>
<s>
The	O
15-meter	B-Algorithm
band	I-Algorithm
opened	O
to	O
amateurs	O
for	O
CW	O
operation	O
only	O
in	O
the	O
United	O
States	O
on	O
May	O
1	O
,	O
1952	O
,	O
and	O
telephony	O
operations	O
were	O
authorized	O
above	O
21.25MHz	O
and	O
Novice	O
CW	O
operations	O
between	O
21.100	O
and	O
21.250	O
MHz	O
on	O
March	O
28	O
,	O
1953	O
.	O
</s>
