Service manual
IM1035
1.5
HUMAN
FACTORS
SPECIFICATION
X-Ray
Radiation
The
TV
50,
90
and 120
Data
monitor
complies
with
the
Federal
Regulation
for
Radiation
Control
as
required
by
the
Radiation
Control
for
Health
and
Safety
Act
of
1968, and
as
implemented by
Title
21,
Subchapter
J
of
the
Code
of
Federal
Regulation.
These
regulations
place
certain
requirements
upon
manufacturers
of
products
which
can
emit
x-rays
under
some
conditions
of
operation
or
failure.
This
in-
cludes
CRT
data
display
monitors.
Label
Visibility
Certification
of
compliance
with
radiation
regulations
is
shown by a
label
attached
to
each
monitor.
The
user
is
responsible
for
labeling
his
product
in
a
similar
fashion
or
in
making
the
DHEW
label
easily
visible
from
the
outside
of
the
enclosure.
The
regulations
state
that
"This
(certification)
information
shall
be
provided
in
the
form
of
a
tag
or
label
permanently
affixed
or
inscribed
on
such
product
so
as
to
be
legible
and
readily
accessible
to
view when
the
pro-
duct
is
fully
assembled
for
use
...
" Each
monitor
is
supplied
with
an
extra
label
attached
to
the
face
of
the
CRT.
The
user
will
remove
this
label
and
use
it
as
stated
above.
Power
Requirements
The
Data
monitor
is
designed
to
operate
and meet
radiation
requirements
when
operated
within
the
respective
AC
or
DC
input
power
specifications.
Radiation
testing
is
performed
at
the
maximum
specified
input
voltage
for
AC
powered
mon-
itors
or
at
130
VAC
for
those
nominally
powered
at
110-120
VAC,
60 Hz.
DC
powered
monitors
have
an
additional
requirement
because
the
DC
source
is
usually
regulated
and
subject
to
failure
of
the
series
pass
element.
This
can
result
in
an
appreciable
increase
in
the
anode
voltage
and
consequent
emission
of
x-rays.
This
is
not
a problem
for
monitors
equipped
with
over
voltage
pro-
tection.
For
monitors
not
so
equipped,
it
is
necessary
for
the
buyer
to
ensure
that
the
normal
adjustment
of
his
regulator
does
not
exceed
the
maximum
level
specified
for
the
particular
monitor.
Furthermore,
he
shall
ensure
that
the
maximum
available
voltage
from
the
supply
cannot
exceed
1.33
times
nominal mon-
itor
input
when
the
supply
has
a
single
failure
such
as
to
cause
the
highest
possible
output
voltage.
User
Operating
Controls
The
only
external
control
required
for
operation
of
the
TV
50,
90,
and 120
dis-
play
unit
is
the
contrast
control.
This
control
is
a
carbon
composition
var-
iable
resistor,
500n±20%;
~
watt.
The
brightness
control
is
mounted on
the
printed
wIrIng
board
and
is
an
in-
ternal
adjustment
by
the
user.
An
option
is
available
where
this
control
is
re-
moved from
the
board
and a remote
brightness
control
supplied
by
the
user
is
utilized.
The
remote
brightness
control
is
a
carbon
composition
variable
resistor,
100kn±20%;
~
watt.
1-7