<s>
The	O
IBM	B-Device
608	I-Device
Transistor	B-Application
Calculator	O
,	O
a	O
plugboard-programmable	O
unit	O
,	O
was	O
the	O
first	O
IBM	O
product	O
to	O
use	O
transistor	B-Application
circuits	O
without	O
any	O
vacuum	O
tubes	O
and	O
is	O
believed	O
to	O
be	O
the	O
world	O
's	O
first	O
all-transistorized	O
calculator	O
to	O
be	O
manufactured	O
for	O
the	O
commercial	O
market	O
.	O
</s>
<s>
The	O
chief	O
designer	O
of	O
the	O
circuits	O
used	O
in	O
the	O
IBM	B-Device
608	I-Device
was	O
Robert	O
A	O
.	O
Henle	O
,	O
who	O
later	O
oversaw	O
the	O
development	O
of	O
emitter-coupled	B-General_Concept
logic	I-General_Concept
(	O
ECL	O
)	O
class	O
of	O
circuits	O
.	O
</s>
<s>
The	O
development	O
of	O
the	O
608	O
was	O
preceded	O
by	O
the	O
prototyping	O
of	O
an	O
experimental	O
all-transistor	O
version	O
of	O
the	O
604	B-Device
.	O
</s>
<s>
To	O
spur	O
the	O
adoption	O
of	O
transistor	B-Application
technology	O
,	O
shortly	O
before	O
the	O
first	O
IBM	B-Device
608	I-Device
shipped	O
,	O
Tom	O
Watson	O
directed	O
that	O
a	O
date	O
be	O
set	O
after	O
which	O
no	O
new	O
vacuum-tube-based	O
products	O
would	O
be	O
released	O
.	O
</s>
<s>
This	O
decision	O
constrained	O
IBM	O
product	O
managers	O
,	O
who	O
otherwise	O
had	O
the	O
latitude	O
to	O
select	O
components	O
for	O
their	O
products	O
,	O
to	O
make	O
the	O
move	O
to	O
transistors	B-Application
.	O
</s>
<s>
As	O
a	O
result	O
,	O
the	O
successor	O
to	O
the	O
IBM	B-Device
650	I-Device
used	O
transistors	B-Application
,	O
and	O
it	O
became	O
the	O
IBM	O
7070the	O
company	O
's	O
first	O
transistorized	O
stored-program	O
computer	O
.	O
</s>
<s>
It	O
was	O
similar	O
in	O
nature	O
of	O
operation	O
to	O
the	O
vacuum-tube	O
IBM	B-Device
604	I-Device
,	O
which	O
had	O
been	O
introduced	O
a	O
decade	O
earlier	O
.	O
</s>
<s>
The	O
608	O
contained	O
more	O
than	O
3,000	O
germanium	O
transistors	B-Application
.	O
</s>
<s>
The	O
use	O
of	O
transistors	B-Application
was	O
a	O
significant	O
departure	O
from	O
the	O
previous	O
IBM	O
calculators	O
of	O
this	O
line	O
.	O
</s>
<s>
The	O
608	O
's	O
transistors	B-Application
made	O
possible	O
a	O
50	O
percent	O
reduction	O
in	O
physical	O
size	O
and	O
a	O
90	O
percent	O
reduction	O
in	O
power	O
requirements	O
over	O
comparable	O
vacuum	O
tube	O
models	O
.	O
</s>
