HP 182C - Page 36

Adjustments
Model 182C
d. Adjust Input
Comp ad] A5C9
for display
of
a
single
diagonal line (no phase
shift).
e. Set
Oscillator for an
output of 100
kHz sine
wave.
f. Adjust Phase adj A5C12
for display of a single
diagonal line (no
phase shift).
g.
Repeat steps b
through f until no
phase shift
occurs
for either
frequency.
h. Disconnect
Oscillator.
i.
Return
Hhase/Bandwidlh switch to
Bandwidth pos-
ition.
5-37.
TRANSIENT RESPONSE ADJUSTMENT.
Note
Omit this
adjustment
procedure
for
normal calibration
arrd perform the
Horiznntal
Linearity Adjustment.
This
procedure
should only be used
If major
repairs or
complete module
replacement has
been made.
a. Set
DISPLAY to EXT
b. Connect
IV
p p
square
wave at 200
kHz repetition
rate
from Square Wave
Generator
to
HORIZONTAL
EXT
INPUT and to
Monitor
Oscilloscope
Vertical input.
c.
Set
Monitor
Oscilloscope time
base to operate
at
sweep
of
1
jUsec/div and
synchronize
Monitor Oscilloscope
with
200
kHz
signal.
d.
Connect
1
psec/div
sweep
signal from
Monitor
Oscilloscope
rear-panel
Main Sweep
Output to
Channel A
input of Model 182C. See
Figure
5-5.
MONITOR
OCILLOSCOPE
IKPUT
o
MAIN &WCEP
OViTPUT ON
REAR
PANSU
"
\
MODEL I62C
CHAN A
INPUT
SQUARE WAVE
GENERATOR
OUTPUT SOfi
son TEE
EXT
INPUT
Figure
5-5. Transient
Response Adjustment Test
Setup
e. Adjust Vertical
plug-in VOLTS/DIV
and
Vernier
controls to obtain
an 8-div display.
f. Observe displayed waveform. At this stage
of
adjust-
ment
waveform will typically exhibit
5%
(approximately
0.5 div) overshoot.
If overshoot
is greater, adjust HF Adj
No. 1 A5C21, HF Adj No. 2 A5C24, and HF Adj
No. 3 A5C28 TO obtain
flat-top
response
with
approx-
imately 5% overshoot on lower right-hand corner of
displayed
pulse.
Note
Capacitors for HF
Adj No. 1
and HF
Adj
No.
3
should be adjusted so their
slugs are almost
equally extended.
g.
Disconnect Monitor Oscilloscope.
5-38.
HORIZONTAL LINEARITY ADJUSTMENT.
Note
Ensure that Time Base has been prop-
erly calibrated before proceeding with
this adjustment.
a.
Set HORIZONTAL DISPLAY to INT.
b.
Connect 4V
p-p 50
MHz sinewave output from
Constant
Amplitude Signal Generator
to
Vertical
plug-in
Channel
A
input.
c.
Set HORIZONTAL
MAGNIFIER
to X10.
d. Select
fastest sweep speed
(.05
or
.1
^isec/div) and
obtain a display.
e. Adjust
HF Adjust No.
1,
No.
2
and No.
3
for best
overall linearity
of
center 80 divisions
of
available display.
Use HORIZONTAL POSITION control to permit viewing
the right,
center
and
left portions of
the
display.
HF Adj No. 1
affects
the right portion, HF Adj No. 2
the center portion and HF Adj No. 3 the left portion of
the
sweep.
f.
Disconnect Constant
Amplitude Signal Generator.
5-39
This completes the adjustment procedure. If de-
sired, the instrument
performance
may be tested to
Model
182C
specifications using the Performance Check
procedure. If satisfactory
adjustment or instrument per-
formance is
not obtained refer to Section VIII of this
manual
for troubleshooting information.
5-8