Ac Assembly (Option 10) - Datron 1061 Calibration And Servicing Handbook

55
CAUTION
The following
procedures should commence
with the
HF
Autocal
vottage close
to-the
center
of its
span'
To
check
this,
select
the
1OoV
RC range and measure
the
DC voltage
at J1'11 with
respect
io
fpS.
lf it
is between
+4V
and
+6V,
it
is
NOT
necessary
to
clear
the calibration
stores'
lf
outside
these
limits, the cal
stores
should
be cleared
as
described
in
para
4.3.1 operatie¡5 (13),
(1a) and
(151'
CLEARING
THE CAL
STORES
ENTAILS
A
FULL
,AUTOCAL'
OF
THE
INSTRUMENT!
Before proceeding;
ensure
that
at leastthe Analog Assembly
LIN
and
I5
Autocalibrations have been
carried
out'
AC
Preamplilier Ze¡o
1.
Read
and
comply
with the CAUTION
above
2
Apply short circuit input.
Select
AC
+
DC, 100mV
range
and HOLD.
3.
Connect
DVM Lo to
TP8, Hi
to
Test
link K (TLK).
Adjust
R148
(bias
current)
for a
reading
of
zero,
*140pV.
Select 100mV
range
AC, and check
that
the
reading
is
zero,
*140¡¡V.
lt
may
be
necessary
to
re-adjust
R149
to
obtain this
value.
lf
so,
recheck operation
3.
Select each range
in turn,
and check
that the
DVM
reading
is within
*70¡¡V
of
zero (except
100mV
range:
*140¡¿V).
Set
up
RMS
Converter
Select
10V
range.
Adjust Rl19 (Rectifier zero) for
the most
negative
(or
least
positive) reading
on
the
display.
Connect
DVM
to TLH.
Adjust
R101
(linearity) for
a
reading
of
+1.1mV410%.
Select
100mV
range. Check
that the DVM
reading
is
between
0.8mV and 1.8mV.
Select
1V
range and apply lV,500Hz, w¡th
the DVM
still
connected
to
TLH.
Remake
links TLC-TLF.
Then after
recording
the TLH
voltage,
refer
to
Fig.
4.2
and
cut the links
(z)
as
appropriate
to
give
a
DVM
reading
of
3.'tS7V *0.010V.
Check Spec
Readout Frequency
Flags
10. Select HOLD. Connect DVM
to
TP6' Adjust
the
applied frequency and note
that TP6
changes
logic
state
at
a
frequency between 1'8kHz and
2'2kHz'
Disconnect the DVM.
I
4.3.4 OPTION
t2
AC
Assembty
Equipment Required:
:
i
'j
[?itîîil';
r';*::
J;
]ï
:f;'
iå
u'ul
%
u'
DC
calibrator.
e.g. Datron 4000
or 4000A.
AC
calibrator.
e.g. Datron 4200.
R'v'..tiiJ'
:ü;-iî"
Fiüél'
c"',
Factor
5:
1
*o'o2o/o'
reversible polarity.
4.
5.
6.
Set Range
'Zetot'
11.
Deselect
HOLD,
and
apply 500H2
atO"lo/o
FR input
to
each
range
in
turn. Perform
ZERO autocal on
each
range, using
the
instrument display
to
check that
ua"h tungt
calibrates
to
100 digits
*3
digits'
Dis'
connect the inPut.
12.
Apply
a
short
circuit to
the input, short Guard
to
Lo
and
select each range
in turn'
Check
that the
reading
on
each range
is
zero
*10
digits on the
display (except
100mV range
*30 digits).
Remove
the shorts'
7
8.
Gain-
1.090
1.084
1.078
1.O72
f .065
1.059
f
.oil
1.O48
1.M2
1.036
1.031
f .025
f .018
1.O12
1.006
1.000
Cut Test Links
F
x
X
x
x
x
x
x
x
E
x
X
x
x
x
x
x
x
D
ta
x
x
x
x
x
x
x
x
c
x
x
X
x
x
x
x
x
TLH
Voltage
2.887
-2.904
2.904
-
2.920
2.920
-2.937
2.937
-2.9æ
2.954
-
2.973
2.973
-2.988
2.988 - 3.004
3.004 - 3.021
3.021 - 3.038
3.038 -
3.055
3.0s5
- 3.071
3.071
- 3.090
3.O90
- 3.1 10
3.tÎ0
-
3.128 {
3.128 - 3.147
3.147 - 3.167
'lncrease in
TLH
voltage
when links are
cut.
FIG.4.3
OPTION 12
AC ASSEMBLY
OUTPUT
SE
LECTION VOLTAGES