HP 8560A Service Manual page 231

495 RBW IOK
496 RBW 100
497 RBW 100
498 RBW 100
499 CAL UNLK
4. Reconnect W17 to A4J7 and monitor the tune voltage at A4J9 pin
5. Press (PRESET) on the spectrum analyzer under test.
6. If the voltage is either +15 V dc or -15 V dc, the Cal Oscillator
An intermittent error 499 indicates the Cal Osc phase-locked-loop
probably can lock at 10.7 MHz, but cannot lock at the 9.9 and 11.5
MHz extremes. This may prevent the Cal Oscillator from adjusting
the 1 MHz or 30 kHz through 300 kHz bandwidths. This symptom
implies a failure in the oscillator, function block X. (See the A4 Log
Amp/ Cal Oscillator schematic sheet 4 of 4.) The oscillator is unable
to tune the required frequency range with the -9 V to i-9 V control
voltage. Troubleshoot A4CR802 (most probable cause),
500 AMPL 30K Unable to adjust amplitude of 30 kHz Resolution Bandwidth.
. l M
501 AMPL Unable to adjust amplitude of 100 kHz Resolution Bandwidth.
502 AMPL .3M Unable to adjust amplitude of 300 kHz Resolution Bandwidth.
503 AMPL 1M Unable to adjust amplitude of 1 MHz Resolution Bandwidth.
504 AMPL 30K Unable to adjust amplitude of 30 kHz Resolution Bandwidth.
505 AMPL .lM Unable to adjust amplitude of 100 kHz Resolution Bandwidth.
506 AMPL Unable to adjust amplitude of 300 kHz Resolution Bandwidth.
5 0 7
AMPL IM Unable to adjust amplitude of 1 MHz Resolution Bandwidth.
508 AMPL 30K Unable to adjust amplitude of 30 kHz Resolution Bandwidth.
Insufficient gain during LC BW Cal.
.lM
509 AMPL Unable to adjust amplitude of 100 kHz Resolution Bandwidth.
Insufficient gain during LC BW Cal.
6-26 General Troubleshooting
Unable to adjust 10 kHz Resolution Bandwidth. XTAL SWP GAIN
Unable to adjust 100 Hz Resolution Bandwidth. Inadequate Q,
Unable to adjust 100 Hz Resolution Bandwidth. Alignment problem.
Unable to adjust 100 Hz Resolution Bandwidth. Gain.
Cal Oscillator is unlocked. Verify the unlocked conditions as follows:
1. Place A4 in its service position and disconnect W51 (gray-yellow)
from A4J7.
2. Connect W51 to the input of another spectrum analyzer. This is
the 10 MHz reference for the Cal Oscillator.
3. If a 10 MHz signal (approximately 0 dBm) is not present, suspect
the Al5 RF assembly, the A21 OCXO, or the Al5 assembly TCXO
(Option 103). If the 10 MHz reference is present, continue with
step 4.
3 with an oscilloscope.
is probably at fault. Normally, the voltage should be near +15 V
during a sweep, and between -9 V and +9 V during retrace.