Agilent Technologies 8564EC Service Manual page 424

Synthesizer Section
Unlocked YTO PLL
16.If a problem exists only at particular CENTER FREQ and SPAN
17.If the fractional N oscillator frequency is not correct, refer to
Check sampler 18.Set A14J23 jumper to the TEST position and set the spectrum
drive output of
A7 LOMA (steps
18-21)
19.Disconnect cable W34 from A15U100J1.
20.Use a power meter to measure the A7 LOMA sampler-drive output
21.Place A14J23 jumper in the NORMAL position and reconnect W34
Check sampler 22.Set the spectrum analyzer to the following settings:
IF (steps 22-26)
23.Place A14J23 jumper in the TEST position.
24.Disconnect W32 from A15J101. Monitor the sampler IF output
25.The sampler IF should measure between 46 MHz and 86 MHz at
26.Set A14J23 jumper in the NORMAL position. Reconnect W32 to
Check FM loop 27.Set A14J23 jumper in the TEST position.
sense (steps
28.Set the spectrum analyzer to the following settings:
27-34)
29.Connect an RF signal-generator output to A14J501. Set the signal
30.Monitor A14J17 pin 1 with a DVM or oscilloscope. Connect ground to
556
settings, determine the desired fractional N oscillator frequency by
pressing ,
CAL MORE 1 OF 2
setting the spectrum analyzer to SINGLE trigger mode.
"Unlocked Fractional N PLL" in this chapter.
analyzer to the following settings:
Center frequency .................................................... 2.9 GHz
Span .............................................................................. 0 Hz
at the end of W34. The power should measure greater than −9 dBm.
to A15U100J1.
Center frequency .................................................. 300 MHz
Span .............................................................................. 0 Hz
(A15J101, SAMPLER IF) with a synthesized spectrum analyzer
such as an 8568A/B or 8566A/B.
−15 dBm to +2 dBm. If the signal frequency or amplitude is
incorrect, refer to "Unlocked Offset PLL" in this chapter.
A15J101.
Center frequency .................................................. 300 MHz
Span .............................................................................. 0 Hz
generator to the following settings:
Frequency .................................................................. 56 MHz
Amplitude .................................................................... 0 dBm
A14J17 pin 6.
, ,
FREQ DIAGNOSE FRAC N FREQ
and
Chapter 11