VXI 3002 - Manual (Page 94)

5-19
(7) Set the UUT RF level to +14 dBm and repeat (5) using Table 5-40.
Pulse modulation on/off ratio
C5358
OUTPUT
Function generator
RF
OUT
UUT
PULSE
INPUT
RF INPUT
Spectrum analyzer
Fig. 5-11 Pulse modulation on/off ratio test set-up
Test procedure
(1) Press CAL on the spectrum analyzer.
(2) Connect the test equipment as shown in Fig. 5-11.
(3) On the UUT set:
Carr Freq 32 MHz
RF Level 0 dBm
Pulse ON
(4) Set the function generator to provide +5 V DC. The RF output will now be enabled
(5) Tune the spectrum analyzer to the same frequency as the signal generator.
(6) Press PEAK FIND on the spectrum analyzer and note the output level.
(7) Apply a short circuit to the PULSE INPUT socket.
(8) Again note the output level measured by the spectrum analyzer.
(9) The difference between the levels recorded in (6) and (8) is the pulse mod on/off ratio.
Check that the ratio is within specification using Table 5-41.
(10) Repeat (5) to (9) for each of the frequencies shown in Table 5-41.