Test Sequence - Datron 4708 User Handbook Manual

7.
Key
Checks
N.B.
The Zero key should not be
pressed until
it
is
desired
to
terminate the Test Sequence.
(a)
t
Keys
Each t key
should
light the
upper half
of
the digit
immediately above
it.
OUTPUT
Display overrange
digit
t
key.
^
Each + key
should
light
the
lower
half
of
the digit
immediately
above
it.
OUTPUT
Display overrange
digit
+
key.
(b)
FREQUENCY RANGE, MODE, OUTPUT RANGE, FUNCTION
and
OUTPUT
keys should cause
their
LEDs
to light,
except:
(i)
Reset
key,
which
is
inoperative,
and
(ii)
Test
key,
which
aborts the
test.
In these
tests
the
key-press operates a
latch
so
that
the display or
LED
remains
lit
until
another
key
is
pressed.
Only one
key-press
at
a time
is
recognized.
(c)
To
Terminate
the
Test Sequence:
Press
Zero key
to
check
its
operation.
-
4708
reverts
to initial
conditions.
-
Test
LED
goes
OFF
(d)
Operate
4708
normally.
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