(7)Set the UUT RF level to +14 dBm and repeat (5) using Table 5-40.

Pulse modulation on/off ratio

 

UUT

 

RF

Function generator

OUT

 

OUTPUT

 

 

PULSE

 

INPUT

 

Spectrum analyzer

 

RF INPUT

 

C5358

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.

5-19

Page 94
Image 94
VXI 3002 manual Pulse modulation on/off ratio, Function generator