HP 209A - High Frequency Adjustment; Distortion Adjustment; Symmetry Adjustment

Model209A
g.
Calculate the average between the most
positive and the most negative error.
h. Readjust
C2
and
C8
for the following
readings on the
XIK
range:
Frequency 20 kHz minus average
found above +/-20
Hz
AGC
-2.0 V +/-0.1 V
Example:
X2
+5%
XlO
+1%
XI00
-1%
XIK
0
XI0K
+2%
Most positive error
+5%
Most negative error
-1
%
Average error (+5%) + (-1%)
=
+2%
2
Adjust frequency for 19,600
Hz
+/-20 Hz.
5-31.
HIGH
FREQUENCY
ADJUSTMENT.
a.
Set the Model 209A RANGE switch
to
XlOOK
and set the Dial to exactly 20.
b. With the Model 209A sine
wave
output
connected to the Frequency Counter, adjust
C5
(HIGH FREQ CAL)
to
indicate 2
MHz
+/-2 kHz on the Frequency Counter.
5-32.
DISTORTION
ADJUSTMENT.
a.
Connect the Model 209A sine
wave
output
to the Distortion Analyzer.
b. Set the Model 209A RANGE switch
to
XIK
and the Dial
to
20.
c.
Set the Distortion Analyzer FUNCTION to
SET LEVEL,
MODE
to MANUAL, and
FREQUENCY RANGE to XIK.
d.
Adjust the Model 209A sine wave amplitude
and Distortion Analyzer SENSITIVITY for
o
dB
meter indication.
e.
Set the Distortion Analyzer Dial and Balance
controls for minimum indication.
Section V
f.
Set the Distortion Analyzer
MODE
to
AUTOMATIC and adjust R30 (DIST) for a
meter indication
of
greater than 60
dB
down
from 0
dB
reference.
5-33.
SYMMETRY
ADJUSTMENT.
a.
Connect the Model 209A square
wave
output to the oscilloscope.
b. Set the Model 209A frequency
to
200 kHz
. and the oscilloscope sweep speed to 0.5
usec/cm.
c.
Set the Model 209A frequency dial for
exactly 1 cycle
of
square wave per 10
centimeters on the oscilloscope.
d.
Adjust the symmetry adjust, R45, for a
symmetrical square wave.
5-34.
FACTORY
SELECTED
COMPONENTS.
5-35. Table
5-5
shows the components that are
factory selected, and how to select the component.
Table 5-5. Factory Selected Components
Component
Selection
Use
smaller value to
AIC4
increase amplifier
bandwidth.
Use
larger value
if
high
AIC9
frequency oscillations
occur at lower frequencies.
AIR7,9,15,17 Chosen for proper
oscillator frequencies.
Use
larger or smaller
AIR36
value to suppress para-
sitic oscillations.
Use
larger value to
AIR82,83 suppress parasitic
oscillation near 2
MHz.
wwwHPARCHIVEcom
5-7