HP 8642A - Page 275

Model 8642A/B
Performance Tests
PERFORMANCE TESTS
4-10. EXTENDED FM DISTORTION TEST
SPECIFICA TION:
DESCRIPTION:
EQUIPMENT:
PROCEDURE:
Electrical Characteristics
Performance Limits
Conditions
FREQUENCY MODULATION
FM Distortion
0.4%
1/15 max dc coupled deviation
(20 Hz
to 100 kHz)
2.0%
1/2 max dc coupled deviation
4.0%
max
dc coupled deviation
All FM distortion specifications are checked by demodulating the signal
with the measuring receiver. The modulation output of the measuring
receiver is then fed into the input of an audio analyzer and measured.
AUDIO
INPUT
ANALYZER
MODULAT ION
OUTPUT
!.:J 0 0 I
10
10 MHz REF EXT
OUTPUT INPUT
MEASURING
o 0 [l DO 0C100n 0 enD
RECEIVER
00 ~o~ §§ §§a§§ 0 ~
HP 8642A/B
RF
RF
SYNTHESIZED
OUTPUT
INPUT
I SENSOR I
SIGNAL GENERATOR
I MODULE I
Figure 4 -6. F M Distortion Test Setup
Measuring Receiver .................. HP 8902A
Sensor Module ........................ HP 11722A
Audio Analyzer ....................... HP 8903A
1.
Connect the instruments as shown in Figure 4-6 and apply power.
Set up HP
8642 as follows:
INSTRUMENT PRESET
AMPLITUDE:
+10 dBm
4-·25