<s>
The	O
Pentagon	B-Device
(	O
ru	O
:	O
Пентагон	O
)	O
home	O
computer	O
was	O
a	O
clone	O
of	O
the	O
British-made	O
Sinclair	B-Operating_System
ZX	I-Operating_System
Spectrum	I-Operating_System
128	O
.	O
</s>
<s>
Its	O
PCB	O
was	O
copied	O
all	O
over	O
the	O
ex-USSR	O
in	O
1991-1996	O
,	O
which	O
made	O
it	O
a	O
widespread	O
ZX	B-Operating_System
Spectrum	I-Operating_System
clone	O
.	O
</s>
<s>
The	O
name	O
"	O
Pentagon	B-Device
"	O
derives	O
from	O
the	O
shape	O
of	O
the	O
original	O
PCB	O
(	O
Pentagon	B-Device
48	O
)	O
,	O
with	O
a	O
diagonal	O
cut	O
in	O
one	O
of	O
the	O
corners	O
.	O
</s>
<s>
Many	O
simple	O
devices	O
(	O
upgrades	O
)	O
were	O
invented	O
to	O
connect	O
to	O
the	O
Pentagon	B-Device
with	O
some	O
soldering	O
.	O
</s>
<s>
The	O
Pentagon	B-Device
1024SL	O
v2.3	O
included	O
most	O
of	O
the	O
upgrades	O
of	O
the	O
standard	O
Spectrum	O
architecture	O
,	O
including	O
1024KB	O
RAM	B-Architecture
,	O
Beta	B-Device
128	I-Device
Disk	I-Device
Interface	I-Device
and	O
ZX-BUS	O
slots	O
(	O
especially	O
for	O
IDE	B-Protocol
and	O
General	O
Sound	B-Device
cards	I-Device
)	O
.	O
</s>
