Vmaintenance; Test Equipment Required; Performance Checks; Fundamental Rejection Check - HP 333A Technical Manual

Model 333A/334A
5-1. INTRODUCTION.
5-2. This section contains maintenance and service
information for the 333A and 334A Distortion Analyz -
Included are Performance Checks, Adjustment
ers.
and Calibration Procedures, and Troubleshooting
Techniques.

5-3. TEST EQUIPMENT REQUIRED.

5-4. Test equipment used in the calibration of the 333A
and 334A is given in Table 5-1, Test Equipment Re-
quired.
This table lists the type of equipment to be
used, required characteristics, and recommended
commercially available test equipment.

5-5. PERFORMANCE CHECKS.

5-6. The Performance Checks are in-cabinet proce-
dures that can be used to verify instrument perform-
ance,
These procedures can be used for periodic
maintenance, to check specifications after a repair,
or for incoming quality control inspection.
5-7. Performance Checks for both the 333A and 334A
are provided. The performance checks are applicable
to both instruments except where noted in paragraph
heading.
5-8. The Performance Checks are performed with the
ac power cord connected to nominal line voltage (115
v/230 V) 50 to 1000 cps, MODE SWITCH to MANUAL,
HIGH PASS FILTER to OUT, and NORM RF DET switch
to NORM, unless otherwise specified. Selector posi-
tions for the SENSITIVITY Selector will be referred
to as follows: MIN=Position 1, next step-Position 2,
etc, to Max= Position 6.

5-9. FUNDAMENTAL REJECTION CHECK

a. Connect 33lA/332A as shown in Figure 5-1.
b. Set Distortion Analyzer controls as follows:
FUNCTION Selector . . . . . . VOLTMETER
METER RANGE Selector . . . . . . . 1 VOLT
FREQUENCY RANGE Selector . . . . . . X1OO
Frequency Dial . . . . . . . . . . . . . . . 50
S e t f i l t e r ( W h i t e I n s t r L a b M o d e l
2640) . . . . . . . . . . . . . . . . . . . . . . . . .5Kc
SECTION V
MAINTENANCE
Figure 5-1. Test Setup for Fundamental Rejection Check
Paragraphs 5-l to 5-9 and Figure 5-1
c. Set Test Oscillator (-hp - Model 651A) frequencv
to 5 K and adjust amplitude for indication of 1.0 volt
C
on Distortion Analyzer meter.
d. Switch Distortion Analyzer FUNCTION to SET
LEVEL. Switch METER RANGE to O. 3 VOLTS. Adjust
SENSITIVITY controls for full scale meter indication.
e. Set Wave Analyzer controls (-hp - Model 302A)
as follows:
SCALE VALUE . . . . . . . . . . RELATIVE
MAX INPUT VOLTAGE . . . . . . . . ...1
RANGE . . . . . . . . . . . . . . 0 DECIBELS
MODE SELECTOR . . . . . . . . . .NORMAL
f. Adjust Wave Analyzer FREQUENCY controls
for maximum meter reading (approximately 1 Kc).
g. Adjust Wave Analyzer REF ADJUST for O db
meter indication.
NOTE
If the range of the REF ADJUST control
is insufficient to set meter to O db refer-
ence, adjust the Distortion Analyzer
SENSITIVITY VERNIER control slightly
to set reference.
h. Switch Distortion Analyzer FUNCTION to DIS-
TORTION. Adjust BALANCE controls and FREQUEN-
CY dial for null indication on Distortion Analyzer
meter. Reduce Distortion Analyzer METER RANGE
selector setting as necessary to maintain deflection
on meter scale.
j. After achieving null indication on Distortion
Analyzer meter, observe Wave Analyzer mete r and
continue to adjust for a null indication. Reduce Wave
Analyzer RANGE setting as necessary to maintain
deflection on meter scale.
NOTE
The Distortion Analyzer OUTPUT is a O
to O. 1 volt signal representing a percent-
age of full scale, regardless of RANGE
TM 11-6625-1576-15
Section V
5-1