Agilent Technologies 8753ES Option 011 Service Manual page 246

Source Troubleshooting
Phase Lock Error
Oscilloscope Method
You need not use the oscilloscope method unless the analog bus is non-functional or any of
the signals fail the specifications listed in
If the analog bus is non-functional or the previous check has revealed questionable signals,
observe the signals with an oscilloscope.
plot for the five signals listed.
Table 7-3 A12 Reference Frequencies
Mnemonic Signal Description
FN100kHzREF 100 kHz Reference
REF Phase Lock Reference
REF Phase Lock Reference
a Fractional-N LO
FN LO *
4MHz REF 4 MHz Reference
2ND LO+/− Second LO
2ND LO+/− Second LO
a. Not an A12 signal, but required for A12 lowband operation.
100 kHz Pulses
The 100 kHz pulses are very narrow and typically 1.5 V in amplitude. You may have to
increase the oscilloscope intensity to see these pulses. (See
Figure 7-8 Sharp 100 kHz Pulses at A13TP5 (any frequency)
7-14
Table 7-2.
Table 7-3 identifies a convenient test point and a
Location See Figure
A13TP5 Figure 7-8
Figure 7-9
A11TP9
A11TP9 Figure 7-10
A14J2 Figure 7-11
A12TP9 Figure 7-12
A12P1-2,4 Figure 7-13
A12P1-2,4 Figure 7-14
Analyzer
Setting
any
≥16 MHz CW
5 MHz CW
10 MHz CW
any
≥16 MHz CW
14 MHz CW
Figure 7-8.)
Chapter 7