HP 8562E, Service Manual

Page: 341 / 482

D e t a i l e d I f M K R 1
1 0
S A M P L E
REF
- 8 4 . 4 0
I I II ill I
L C P O L E L C P O L E LC POLE
S E T T I N G S P A S T H E R E A R E F O R
A U T O M A T I C A D J U S T M E N T O F T H E
3 0 k H z R E S O L U T I O N B A N D W I D T H
CENTER
1 0 . 7 0 0 0 0 0 M H z SPAN 0 Hz
R E S B W 3 0 0 VBW 1 2 . 0 0
Figure 9-8. Detailed IF Adjust Signature (5)
Region A of Figure 9-4 is noisy:
Suspect the first LC pole.
Region B of Figure 9-4 is flat:
Suspect the third step-gain stage, the fine attenuator, or the fourth LC-pole output
amplifier.
Region C of Figure 9-4 has no 15 step:
Suspect the reference 15 attenuator.
Region D of Figure 9-4 is flat:
Suspect the second step-gain stage.
Entire signature noisy:
If the signature resembles Figure 9-9, suspect a broken first step-gain stage or a break in
the signal path in the input switch, first crystal pole, or second crystal pole.
Correct shape but noisy:
If the signature resembles Figure suspect the second crystal-pole output amplifier.
Amplitude of Region B of Figure 9-11 varies more than 12
Suspect the third step-gain stage output amplifier.
Region B of Figure 9-12 is kinked:
Suspect the fourth LC-pole output amplifier.
9-26 IF Section