<s>
In	O
electronics	O
,	O
a	O
Dekatron	B-General_Concept
(	O
or	O
Decatron	B-General_Concept
,	O
or	O
generically	O
three-phase	B-General_Concept
gas	I-General_Concept
counting	I-General_Concept
tube	I-General_Concept
or	O
glow-transfer	B-General_Concept
counting	I-General_Concept
tube	I-General_Concept
or	O
cold	O
cathode	O
tube	O
)	O
is	O
a	O
gas-filled	O
decade	O
counting	B-General_Concept
tube	I-General_Concept
.	O
</s>
<s>
Dekatrons	B-General_Concept
were	O
used	O
in	O
computers	O
,	O
calculators	O
,	O
and	O
other	O
counting-related	O
products	O
during	O
the	O
1950s	O
and	O
1960s	O
.	O
</s>
<s>
"	O
Dekatron	B-General_Concept
,	O
"	O
now	O
a	O
generic	O
trademark	O
,	O
was	O
the	O
brand	O
name	O
used	O
by	O
Ericsson	O
Telephones	O
Limited	O
(	O
ETL	O
)	O
,	O
of	O
Beeston	O
,	O
Nottingham	O
(	O
not	O
to	O
be	O
confused	O
with	O
the	O
Swedish	O
TelefonAB	O
Ericsson	O
of	O
Stockholm	O
)	O
.	O
</s>
<s>
The	O
dekatron	B-General_Concept
was	O
useful	O
for	O
computing	O
,	O
calculating	O
,	O
and	O
frequency-dividing	O
purposes	O
because	O
one	O
complete	O
revolution	O
of	O
the	O
neon	O
dot	O
in	O
a	O
dekatron	B-General_Concept
means	O
10	O
pulses	O
on	O
the	O
guide	O
electrode(s )	O
,	O
and	O
a	O
signal	O
can	O
be	O
derived	O
from	O
one	O
of	O
the	O
ten	O
cathodes	O
in	O
a	O
dekatron	B-General_Concept
to	O
send	O
a	O
pulse	O
,	O
possibly	O
for	O
another	O
counting	O
stage	O
.	O
</s>
<s>
Dekatrons	B-General_Concept
usually	O
have	O
a	O
maximum	O
input	O
frequency	O
in	O
the	O
high	O
kilohertz	O
(	O
kHz	O
)	O
range	O
–	O
100kHz	O
is	O
fast	O
,	O
1MHz	O
is	O
around	O
the	O
maximum	O
possible	O
.	O
</s>
<s>
These	O
frequencies	O
are	O
obtained	O
in	O
hydrogen-filled	O
fast	O
dekatrons	B-General_Concept
.	O
</s>
<s>
Dekatrons	B-General_Concept
filled	O
with	O
inert	O
gas	O
are	O
inherently	O
more	O
stable	O
and	O
have	O
a	O
longer	O
life	O
,	O
but	O
their	O
counting	O
frequency	O
is	O
limited	O
to	O
10kHz	O
(	O
1	O
–	O
2kHz	O
is	O
more	O
common	O
)	O
.	O
</s>
<s>
Internal	O
designs	O
vary	O
by	O
the	O
model	O
and	O
manufacturer	O
,	O
but	O
generally	O
,	O
a	O
dekatron	B-General_Concept
has	O
ten	O
cathodes	O
and	O
one	O
or	O
two	O
guide	O
electrodes	O
plus	O
a	O
common	O
anode	O
.	O
</s>
<s>
Hydrogen	O
dekatrons	B-General_Concept
require	O
high	O
voltages	O
ranging	O
from	O
400	O
to	O
600	O
volts	O
on	O
the	O
anode	O
for	O
proper	O
operation	O
;	O
dekatrons	B-General_Concept
with	O
inert	O
gas	O
usually	O
require	O
~	O
350	O
volts	O
.	O
</s>
<s>
When	O
a	O
dekatron	B-General_Concept
is	O
first	O
powered	O
up	O
,	O
a	O
glowing	O
dot	O
appears	O
at	O
a	O
random	O
cathode	O
;	O
the	O
tube	O
must	O
then	O
be	O
reset	O
to	O
zero	O
state	O
,	O
by	O
driving	O
a	O
negative	O
pulse	O
into	O
the	O
designated	O
starting	O
cathode	O
.	O
</s>
<s>
Counter	O
(	O
common-cathode	O
)	O
dekatrons	B-General_Concept
have	O
only	O
one	O
carry/borrow	B-Algorithm
cathode	O
wired	O
to	O
its	O
own	O
socket	O
pin	O
for	O
multistage	O
cascading	O
and	O
the	O
remaining	O
nine	O
cathodes	O
tied	O
together	O
to	O
another	O
pin	O
;	O
therefore	O
they	O
do	O
n't	O
need	O
bases	O
with	O
more	O
than	O
9	O
pins	O
.	O
</s>
<s>
Counter/Selector	O
(	O
separate-cathode	O
)	O
dekatrons	B-General_Concept
have	O
each	O
cathode	O
wired	O
to	O
its	O
own	O
pin	O
;	O
therefore	O
their	O
bases	O
have	O
at	O
least	O
13	O
pins	O
.	O
</s>
<s>
This	O
kind	O
of	O
versatility	O
made	O
such	O
dekatrons	B-General_Concept
useful	O
for	O
numerical	O
division	O
in	O
early	O
calculators	O
.	O
</s>
<s>
Dekatrons	B-General_Concept
come	O
in	O
various	O
physical	O
sizes	O
,	O
ranging	O
from	O
smaller	O
than	O
a	O
7-pin	O
miniature	O
vacuum	O
tube	O
to	O
as	O
large	O
as	O
an	O
octal	O
base	O
tube	O
.	O
</s>
<s>
While	O
most	O
dekatrons	B-General_Concept
are	O
decimal	O
counters	O
,	O
models	O
were	O
also	O
made	O
to	O
count	O
in	O
base-5	O
and	O
base-12	O
for	O
specific	O
applications	O
.	O
</s>
<s>
The	O
dekatron	B-General_Concept
fell	O
out	O
of	O
practical	O
use	O
when	O
transistor-based	O
counters	O
became	O
reliable	O
and	O
affordable	O
.	O
</s>
<s>
Today	O
,	O
dekatrons	B-General_Concept
are	O
used	O
by	O
electronic	O
hobbyists	O
in	O
simple	O
"	O
spinners	O
"	O
that	O
run	O
off	O
the	O
mains	O
frequency	O
(	O
50Hz	O
or	O
60Hz	O
)	O
or	O
as	O
a	O
numeric	O
indicator	O
for	O
homemade	O
clocks	O
.	O
</s>
