Datron 1062 - Page 69

56
Set up
DC-DC
Turnover
13. Select
IV range,
AC
+
DC.
Apply IV
500Hz
and
perform GAIN
autocal.
14.
Apply
+1V
DC
and note
the
displayed
reading.
15. Apply
-IV
DC
and adjust R62
(DC
turnover)
for the
same
reading as
in operation (14).
(±3
digits).
16.
Repeat
(13)
to
(15)
until
all readings
are the
same to
within
i20
digits.
Set up Coarse
Frequency
Response
17. Select
100V
range, AC;
apply 100V,
500Hz and
perform GAIN
autocal.
Apply 100V,
50kHz
and
adjust
C82
for
a
display
reading of
100.000V ±20
digits. (If
necessary
change C81 to
a
value
which
permits this
adjustment).
18. Apply
100V,
100kHz and
note the
reading
error.
Adjust
C79
to
give 5
times
the
error
in
the
same
direction.
19. Repeat
(17)
and
(18)
until the
50kHz
and 100kHz
readings are
separated by
less
than
20
digits.
20.
Select IV
range, AC;
apply
IV, 5(X)Hz
and
perform
GAIN autocal.
Apply IV,
50kHz and adjust
C84
for a
display
reading of 1.00000V
±20
digits.
(If
necessary
change
C85
to a
value
which
permits this
adjustment).
Set up
Crest Factor
21. Apply 1VRMS,
+ve
5:1 Crest
Factor signal. Adjust
R61
(crest factor) for a
display
reading of 1.00000V
±30 digits.
22.
Apply 1VRMS,
-ve
5;1 Crest
Factor
signal. Check
that
display reading is
1 .OOOOOV
±30 digits.
23.
Apply IV,
500Hz, and
perform GAIN
Autocal.
Repeat
(21),
(22)
and
(23)
until crest
factor readings
are
within limits.
Linearity Checks
24.
Select
IV range, AC
+
DC.
Apply IV
DC
and
perform
GAIN
Autocal.
25.
Apply 1 .9V DC
and
adjust
R27
value
(Factory
Selected
Value
-
FSV)
for
a
display
reading
of 1.90000V
±6
digits
(reducing
R27
increases
reading).
26.
Repeat
(24)
and
(25)
until
both
correct.
27.
Select IV
range
AC.
Apply in
turn
IV, lOOmV,
lOmV, at
500Hz and
check
that
display
reading is
correct to
within ±10
digits
of the
input
voltage.
28.
Apply
open
circuit input,
set
CAL/RUN
switch to
RUN;
press
'Test'
and
check
for
a
display
of 'PASS'.
Output
Buffer
Check
29.
Select
IV
range, AC+ DC,
no
filter.
Apply IV DC
and
set
CAL
switch to
RUN. Use
the
'A-B' computation
mode
to
null
out
the
reading: press
STORE, B,
then
(A-B).
30.
Select
filter, and leave to
settle
for at
least 30
seconds.
Check
that
the
displayed
reading is
within ±50
digits
of zero.
31.
Repeat (28).
The AC
set-up
procedure
is now
complete.