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I
Model 5245L
Table
3-2.
In-Cabinet Performance Check (cont'd)
b.
Counter should count 10,000.000
kHz.
The
change
in
count
should
be
visible
on each
digital display
tube.
c.
Set
Counter
STORAGE
switch to the
STORAGE
position.
The
Counter should count, display,
and
hold 10,000,000 kHz count providing a continuous display of the most recent
count.
Record
results
on
test
card.
SAffIPtE
RATE
1.
Sample
Rate: Variable from less than .2
sec
to greater than 5
seconds.
a.
Set
Counter
controls as follows:
SENSITMIY to
CHECK
SAMPLE RATE
tO POWER
OFF
TIME
BASE
to
10
ms
FUNCTION
to
FREQUENCY
-
LEVEL
+
to
PRESET
b.
Connect
Oscilloscope
to Jl1
Pin
48.
c.
Turn the Counter SAMPLE RATE control slightly clockwise out of
POWER
OFF,
and
note
that
the
Counter
turns
on.
d.
With the SAMPLE RATE control in
ma.:<imum
position (ccw), observe with oscilloscope the
negative
pulse
duration between gate closing
and
the
following gate opening;
it
should
be
less than
200
milli-
seconds
(.2
sec).
e.
Increase
the SAMPLE RATE control clocl$vise to minimum sample
rate.
Observe
with
Oscilloscope
the negative
pulse duration
between
gate
closing
and
the
following gate openingl
it
should be more
than 5
seconds.
f.
Set
the SAMPLE RATE control to the Hold
position.
The
last Counter reading
should
remain dis-
played
indefinitely.
Record
results
on
test
card.
DIGITAI
OUTPUT
1
Output
4 line
l-2-2-4
BCD:
Impedance
100K each
line
"0"
State
Level -8V
"1"
State
Level
+18V
a,
The impedance
is
determined
by
a
fixed value
100K
resistor,
which
can
be
seen
in
schematic
diagrams Figures
7-9
,
?-11
,
and
?- 14.
b.
Set
Counter controls
as
follows:
SAMPLE
RATE slightty clockrvise out of
POWER
OFF
SENSITMTY to
.
ls
TIME
BASE
to
1
/.rs
FUNCTION
to MA}IUAL
START
MODE
(rear
panel)
to INT
STD
FREQ
c.
Connect
Oscilloscope
to following points to
verify "0"
state
and
'r1'r
state
levels.
Oscilloscope
will
display the switch
from "0"
state (-8 volts) to
"1"
state
(+18
volts)
as
a
positive
26
volts
step.
Check
all recorder
outputs
for "0"
state
and
"1"
state
and
mark the test card
ok.
Section
trI
Table 3-2
02349-1
3-9
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