<s>
ELKA	B-Device
(	O
)	O
is	O
a	O
Bulgarian	O
brand	O
of	O
electronic	O
calculator	O
,	O
developed	O
by	O
the	O
Central	O
Institute	O
for	O
Computation	O
Technologies(bg )	O
and	O
built	O
at	O
the	O
Elektronika	O
plant	O
in	O
Sofia	O
.	O
</s>
<s>
The	O
name	O
is	O
a	O
contraction	O
of	O
ЕЛектронен	O
КАлкулатор	O
,	O
or	O
"	O
electronic	O
calculator	O
"	O
,	O
and	O
the	O
word	O
elka	B-Device
has	O
,	O
by	O
extension	O
,	O
become	O
the	O
generic	O
name	O
for	O
a	O
calculator	O
.	O
</s>
<s>
The	O
first	O
model	O
,	O
the	O
ELKA	B-Device
6521	O
,	O
was	O
introduced	O
in	O
1965	O
,	O
shipped	O
from	O
1966	O
,	O
and	O
used	O
germanium	O
transistors	B-Application
and	O
a	O
nixie	B-Application
tube	I-Application
display	O
.	O
</s>
<s>
Later	O
,	O
the	O
models	O
ELKA	B-Device
22	I-Device
(	O
again	O
,	O
with	O
a	O
nixie	B-Application
tube	I-Application
display	O
)	O
and	O
ELKA	B-Device
25	O
,	O
(	O
with	O
a	O
built-in	O
printer	O
)	O
were	O
developed	O
.	O
</s>
<s>
These	O
models	O
had	O
a	O
plastic	O
case	O
and	O
were	O
based	O
again	O
on	O
discrete	O
technology	O
,	O
their	O
numerous	O
phenolic	O
boards	O
being	O
populated	O
with	O
hundreds	O
of	O
transistors	B-Application
,	O
diodes	O
and	O
resistors	O
,	O
plus	O
a	O
magnetic-core	O
memory	O
.	O
</s>
<s>
In	O
1972	O
this	O
developed	O
the	O
lighter	O
and	O
more	O
portable	O
,	O
but	O
still	O
relatively	O
large	O
calculator	O
models	O
ELKA	B-Device
40	O
and	O
ELKA	B-Device
42	O
built	O
around	O
integrated	O
circuits	O
(	O
medium-scale	O
integration	O
)	O
.	O
</s>
<s>
These	O
had	O
again	O
nixie	B-Application
tube	I-Application
displays	O
.	O
</s>
<s>
Later	O
models	O
in	O
the	O
1970s	O
were	O
the	O
ELKA	B-Device
50	O
and	O
ELKA	B-Device
1300	O
,	O
which	O
had	O
a	O
similar	O
outward	O
appearance	O
and	O
used	O
vacuum-fluorescent	O
tube	O
displays	O
and	O
relatively	O
expensive	O
but	O
very	O
reliable	O
reed-switch	O
keyboards	O
.	O
</s>
<s>
Meanwhile	O
,	O
the	O
ELKA	B-Device
77	O
was	O
the	O
first	O
electronic	O
cash	O
register	O
.	O
</s>
<s>
The	O
first	O
pocket	O
model	O
was	O
the	O
ELKA	B-Device
101	O
,	O
introduced	O
in	O
1974	O
.	O
</s>
<s>
This	O
was	O
the	O
first	O
in	O
a	O
large	O
series	O
,	O
including	O
the	O
scientific	O
ELKA	B-Device
135	O
.	O
</s>
<s>
Other	O
models	O
in	O
the	O
100	O
series	O
included	O
the	O
ELKA	B-Device
103	O
,	O
105	O
,	O
131	O
and	O
130M	O
.	O
</s>
<s>
As	O
of	O
2013	O
the	O
factory	O
in	O
Silistra	O
,	O
now	O
named	O
"	O
Orgtehnika	O
"	O
,	O
still	O
produces	O
mostly	O
vending	O
oriented	O
machines	O
branded	O
ELKA	B-Device
:	O
cash	O
registers	O
,	O
electronic	O
scales	O
,	O
taxi	O
meters	O
,	O
etc	O
.	O
</s>
