Operating instructions

OPERATING MANUAL 2945A
46882-311D 5-7
(4) Decrement the output of the UUT in 10 dB steps down to an RF level of
−
121 dBm
measuring the RF level at each step.
(5) Repeat steps 2 to 4 for frequencies of 500 and 1000 MHz.
Alternative attenuator functional check
C2583
UUT
Spectrum analyzer
N TYPE
OUTPUT
Fig. 5-4 Attenuator functional check
(1) Connect the test equipment as shown in Fig. 5-4.
(2) Set the UUT to [Rx TEST], RF IN/OUT [SELECT] N-type output, [RF Gen],
[LEVEL]
−
27 dBm, [
∆
INC] 10 dB, [FREQ] 251 MHz. All modulation and noise
measurements should be switched OFF.
(3) Tune the Spectrum analyzer to the signal from the UUT. Using the UUT increment level
down arrow key, reduce the level of the UUT output in 10 dB steps down to
−
127 dBm. At
each 10 dB step ensure the level on the analyzer drops accordingly
Spectral purity
Harmonics, spurious, RF carrier leakage, residual FM.
Specification
Carrier range: 400 kHz to 1 GHz
Harmonics: Better than −20 dBc.
Spurious signals Better than −30 dBc (±
10 kHz to 1.5 MHz offset from carrier
frequency or over range 600 - 700 MHz). Better than −40 dBc
elsewhere.
Carrier leakage Less than 0.5 µV PD generated in a 50 Ω load by a 2 turn 25 mm loop
25 mm from the case with output level less than −40 dBm and
terminated in a sealed 50 Ω load.
Residual FM Less than 15 Hz RMS (0.3 to 3.4 kHz) up to 500 MHz
Less than 20 Hz RMS (0.3 to 3.4 kHz) up to 1000 MHz (with OCXO)