Datron 1061 Calibration And Servicing Handbook page 65

54
4.3.3 OPTION
10 AC
Assembty
Equipment
Required:
SmV/Div
oscilloscope.
e.g.
Telequipment D83'
5%
digit
DVM with Ohrni...g. oation
1065, 1061'
DC
calibrator.
e.g. Datron 4000 or
40004.
AC
calibrator.
e.g.
Datron 4200.
Asymmetric signal,
1V
RMS,
Crest Factor
5:1
*O'O2Yo,
reversible
polarity.
Select
AC
l00OV
range
and
HOLD' Short
Hi
to
Lo'
Connect DVM
H¡
to TL7,
Lo
to
TPB
and
note
read'
ing.
Select
1V
range
and
adiust R121
(bias
current)
to
give
same reading *.1O¡rV.
Select 100mV
range,
AC
+
DC and adjust
R112
(offset adjustl
for
an indication
of
zero
!50PV
on
the DVM.
3.
Repeat steps
1'
and
2. until
readings are
within
the
specified limits.
4.
Select 10V
range
and HOLD.
Connect oscilloscope Hi
to
TP5,
Lo to
TP8
and
adjust R90 (rectifier
zero)
for
maximum
noise about zero.
Remove
the
oscillo'
scope.
Connect DVM
Hi to
TP2,
Lo
to
TPB
and
adjust
R75
(linearity)
for
an indication on the DVM of
1.8mV +1oo/o.
Select
AC, 1V range,
FILTER and
apply 1V
500H2.
Connect
DVM H¡
to TLs,
Lo
to
TP8.
lf
reading
is
+3.157V 1.0.01V
Proceed
to
step 8.
Disconnect
input
signal and switch
off
instrument,
Make
links
TL1 to TL4 if
cut. Switch on instrument,
reselect
AC,
lV
range,
FILTER and reapply
lV,
500H2.
Measure
voltage
on TLS.
Consult Fig.
4.2
and
cut links as indicated. Check
voltage
on TLS
is
3.157V
t0.01V.
Remove
the DVM.
Deselect
HOLD
and
short circuit instrument Hi
and
Lo. Turn rear
panel key switch
to
CAL
mode
and
select
ZERO.
Repeat
for
all
ranges.
Select
1V
range.
Apply
1
volt
(d.c.) and
note
reading
on
display.
Apply
-1
volt
(d.c.) and
adjust
R50
(d.c. turnover)
for
same
display indication
+ 10 digits.
10.
This part
of
the procedure must
be
performed
with
the
high frequency
compensation voltage,
at
J1-111
Rb7, at
_SV +0.2V.
a.
Select
AC 100V range,
FILTER
and
apply
100V,
S00Hz. Select
GAIN. Apply 100V, S0kHz
and
adiust C62
for
a
display
of
100.000V
+20
digits.
b. Apply 100V,
100kHz note
error and adjust
C61
to
double the
displayed error in the
same
direct-
ion.
c.
Repeat
a. and
b.
until
50kHz and 100kHz
displays
are
within
+20 disits.
d.
Select
1V
range and apply
1
volt, 500 Hz. Select
GAIN. Apply
lV
50kHz and adjust C63
for
a
display
of
1.00000V +20
digits.
11
Apply 1 volt 5:1
crest factor
signal.
Adjust
R35
(crest factor)
for
a display
of
1.00000V
+30
digits.
12.
Open
circuit input. Turn
rear panel
key switch to
RUN. Select TEST and check
for
a
display
of
PASS.
Turn rear panel
key sw¡tch
to
CAL.
13.
Select
10V
range
and apply 10V, 50kHz.
Check
display
is '10.0000V
+'1200 digits. Check
that
the
display
can be
calibrated
to
10.0000
+20
digits
by
less
than
5 presses
of the AC HF key.
14.
Select 100mV range and apply 100mV
50kHz.
Check
display is 100.000mV
-+-500
digits'
Check
that
display can be calibrated
to
100.000mV
+20
digits
by
less
than
Slcresses
of
the AC HF key.
15.
Select
1000V
range
and
apply 1000V,500Hz.Select
GAIN.
16.
Apply 1000V, 25kHz and check
displav is 1000.00V
+1200 digits. Check that
display
can be calibrated
to
1000.00V
+20 digits by
less
than
5
presses
of
the
AC HF
key.
Remove
1000V and
turn
rear
panel key
switch
to
RUN.
The basic
AC set'up procedure
is
complete
Procedure
1
2.
5.
b
7
8.
I
TL4
7
/
/
7
TL3
:
{
a
7
a
TL2
:
7
{
TLl
:
-
7
Voltage
on
TL5
3.157
3.174
3.198
3.218
3.239
3.259
3.280
3.300
3.320
3.340
3.360
3.380
3.400
3.420
3.440
3.460
Select voltage closest
to measured value
and
cut
l¡nks
F'G 4.2 OPTION 1O
AC ASSEMBLY OUTPUT
SELECTION VOLTAGES