Aeroflex 2023A - Internal FM; FM Deviation and Distortion

ACCEPTANCE TESTING
7-17
Internal FM
Specification
Deviation range:
CW range (MHz) Max. deviation (kHz)
1200 to 2510 12800
600 to 1200 6400
300 to 600 3200
150 to 300 1600
75 to 150 800
37.5 to 75 400
18.75 to 37.5 200
0.009 to 18.75 100
Resolution:
3 digits or 1 Hz
Bandwidth (1 dB):
DC to 275 kHz (DC coupled)
10 Hz to 275 kHz (AC coupled)
20 Hz to 275 kHz (AC coupled with ALC)
Group delay:
Less than 5 μs to 100 kHz
Accuracy:
±4% at 1 kHz modulation rate
Carrier frequency offset:
Less than 1% of the set frequency deviation when DC coupled
Distortion:
Less than 1% at 1 kHz rate for deviations up to 20% of max. available
deviation. Typically 0.1% for deviations of 2% of max. available
deviation and less than 3% at max. available deviation.
Test equipment
Description Minimum specification Example
Modulation meter
FM accuracy ±1% at 1 kHz modulation frequency
Aeroflex 2305
with distortion
option
DVM DC voltage measurement Solartron 7150+
50 Ω load
(termination)
1 W, 50 Ω nominal impedance, DC to 2.51 GHz
Lucas Weinschel
M1404N
Audio analyzer Capable of measuring THD of 0.01% from 100 Hz
to 20 kHz
Rohde & Schwarz
UPA3
Function gen.
DC to 100 kHz sine, ±0.6 dB flatness
Agilent 3325B
FM deviation and distortion
Test procedure
UUT
2305
Modulation meter
C2367
RF OUTPUT
RF INPUT
Fig. 7-8 Internal modulation and modulation distortion test set-up
(1) Connect the test equipment as shown in Fig. 7-8.