Keithley 177 Instruction Manual page 35

Table
5-7.
AC
Converter
Checks
Step
Item/Component
Required Condition
Remarks
1
Turn on power.
Select
2VAC
range.
NOTE:
Full
scale input
on
all
ranges should produce
ss2V rms
output
at
TPS*.
2 Externa! voltage
source.
Apply
IV rms
at 1kHz. Calibrated
input.
3
XP10*
.99V rms
nominal.
Output
of
U101 and
feed-
back
components R108
and
C103
(nominal gain
.99).
4
TPS*
,993V rms nominal. Output
of
U102. (Q102
on,
nominal gain
1.003).
5
U103
Pin
6
or
TP1*
+ 1V
Output
of
U103. Gain
of
U103
adjusted to provide
+ 1VDC
output
for
1VAC
{
scale) input.
6
External
voltage
Select
20VAC
range.
Apply 10V
Gain
check
of U101
and
source.
rms
at
1kHz. U102. Nominally, .0099
(UlODand
10.03 (U102).
7
TP10
.099V rms
nominal.
Output
of
U101 and
feed-
back components
R109,
C104and
Q101
(on).
8
JP8
.993V rms nominal. Output
of
U102 (0102
off).
9
External
voltage
Select
1000V
AC
range.
Apply
Calibrated
input.
Check
source.
10000V rms
at 1kHz. gain of
U101
(nominal
.00099).
10
TP10
.99V rms
nominal.
Output
of
U101 and
feed-
back
components
K101,
RllOand
C105, K101
(Closed).
11
External voltage
source.
Select
200VAC
range.
Apply 100V
rms
at 20kHz.
Calibrated
input.
12 Display 100.00 nominal.
High frequency response
(compensation C102, C103,
C104).
13 External voltage
source.
Select
2VAC
range.
Apply IV rms
at 20kHz.
Calibrated input.
14 Display
1.0000 nominal
High frequency response.
(Compensation
C102,
C103).
15
External voltage
source.
Select
1000VAC
range.
Apply
1000V rms
at
20kHz.
16 Display 1000.0
± nominal.
High frequency response.
(Compensation
C102, C103,
C105).
17 External voltage
source.
Select
2VAC
range.
Apply IV
rms
at
45Hz.
18 Display
1.0000V ± nominal.
Low
frequency response,
C101, C106, C107, C108,
C109.
*See
Figure 5-1.