Anritsu MS8608A, Operation Manual, Page: 122 / 338

Section 6 Performance Tests
6-10
Temperature stability: Test this performance in a vibration-free constant-temperature
chamber.
Step Procedure
1
Set up the spectrum analyzer in a constant-temperature chamber at 25
°
C in the same setup.
2
Set the LINE and Power switches on the spectrum analyzer to On and wait until the spectrum
analyzer internal temperature stabilizes (approx. 1.5 hours after the chamber temperature
stabilizes).
3 When the internal temperature stabilizes, measure the frequency by using the counter with 0.1
mHz resolution.
4
Change the chamber temperature to 50
°
C.
5 When the chamber temperature and the spectrum analyzer internal temperature re-stabilize,
measure the frequency by using the counter.
6 Calculate the stability by using the following equation.
(counter reading at 50
°
C) – (counter reading at 25
°
C)
(counter reading at 25
°
C)
Temperature stability =
7
Change the chamber temperature to 0
°
C and repeat steps 5 and 6.
Frequency readout accuracy
Add the known frequency which serves as the center frequency reference to the spectrum
analyzer as shown in the figure below and set CF (same value as the known reference
frequency) and SPAN. At this time, check that the difference between the reading of
the marker readout frequency (thick arrow in the figure) of the center frequency peak
point.
As shown in the figure, the Synthesized Signal Generator uses the signal source phase-
locked with the same accuracy as the 10 MHz reference oscillator of the spectrum
analyzer.
(1) Specification
Frequency readout accuracy:
±
(readout frequency
×
reference frequency ac
span
×
span ac resolution bandwidth
×
0.15 + 10 Hz)