RE F/ I”.; dBmi ATTEN 20 dB

5dB,’

S A M P L E

1 I I I I

C E N T E R 1 0 . 7 0 0 0 0 0

MHz

 

S P A N 0 H z

R E S B W 3 0 0

kHz

 

V B W 3 0 0 kHz

S W P 5 0 0 set

S K 1 8 1

Figure 8-12. Region B Amplitude Offset

1 MHz Resolution Bandwidth Problems

Check the crystal shorting switches as follows:

1. On the spectrum analyzer, press [PRESET) and set the controls as follows:

RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . l M H z 500kHz

FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..300MH z

2.On the spectrum analyzer, connect the 300 MHz CAL OUTPUT to the INPUT 50ohm.

3.If the trace flatness is not within 2.5 dB, a failure probably exists.

4.A trace similar to Figure 8-13 indicates a crystal short failure.

5.Set the spectrum analyzer (SPAN) to 3 MHz. A trace that slopes across the screen (see Figure 8-14) indicates a failed LC pole. To isolate the broken pole refer to the shape factor information in “30 kHz Resolution Bandwidth Problems.”

8-30 IF Section