<s>
The	O
Sinclair	B-Device
Executive	I-Device
was	O
the	O
world	O
's	O
first	O
"	O
slimline	O
"	O
pocket	O
calculator	O
,	O
and	O
the	O
first	O
to	O
be	O
produced	O
by	O
Clive	O
Sinclair	O
's	O
company	O
Sinclair	O
Radionics	O
.	O
</s>
<s>
Introduced	O
in	O
1972	O
,	O
there	O
were	O
at	O
least	O
two	O
different	O
versions	O
of	O
the	O
Sinclair	B-Device
Executive	I-Device
,	O
with	O
different	O
keyboard	O
markings	O
,	O
and	O
another	O
called	O
the	O
Sinclair	B-Device
Executive	I-Device
Memory	O
,	O
introduced	O
in	O
1973	O
.	O
</s>
<s>
The	O
parts	O
,	O
consisting	O
of	O
the	O
TMS1802	O
chip	O
,	O
22	O
transistors	B-Application
,	O
50	O
resistors	O
and	O
17	O
capacitors	O
,	O
cost	O
close	O
to	O
,	O
compared	O
with	O
a	O
sale	O
price	O
of	O
close	O
to	O
.	O
</s>
<s>
A	O
Sinclair	B-Device
Executive	I-Device
purchased	O
by	O
a	O
Russian	O
diplomat	O
exploded	O
in	O
his	O
breast	O
pocket	O
,	O
allegedly	O
leading	O
to	O
an	O
official	O
Soviet	O
investigation	O
.	O
</s>
<s>
According	O
to	O
a	O
Sinclair	B-Device
executive	I-Device
quoted	O
in	O
the	O
Financial	O
Times	O
,	O
"	O
one	O
must	O
always	O
bear	O
a	O
packet	O
of	O
cigarettes	O
in	O
mind	O
as	O
the	O
ideal	O
size	O
,	O
"	O
possibly	O
a	O
quip	O
on	O
Clive	O
Sinclair	O
's	O
smoking	O
habit	O
.	O
</s>
<s>
The	O
Executive	O
could	O
carry	O
out	O
sums	O
to	O
two	O
,	O
four	O
or	O
six	O
decimal	B-Architecture
places	I-Architecture
,	O
or	O
use	O
a	O
floating	B-Algorithm
decimal	I-Algorithm
point	I-Algorithm
.	O
</s>
<s>
The	O
calculator	O
was	O
powered	O
by	O
a	O
Texas	O
Instruments	O
TMC1802NC	O
,	O
a	O
metal	B-Architecture
oxide	I-Architecture
semiconductor	I-Architecture
integrated	O
circuit	O
with	O
7000	O
transistors	B-Application
.	O
</s>
<s>
This	O
CPU	B-Device
normally	O
consumes	O
350	O
milliwatts	O
,	O
but	O
by	O
pulsing	O
the	O
power	O
this	O
requirement	O
was	O
reduced	O
to	O
20	O
milliwatts	O
.	O
</s>
<s>
Power	O
is	O
supplied	O
to	O
the	O
chip	O
in	O
1.7	O
microsecond	O
pulses	O
as	O
determined	O
by	O
the	O
storage	O
time	O
of	O
a	O
control	O
transistor	B-Application
.	O
</s>
