Agilent Technologies 8564EC, Service Manual

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330 Chapter 7
General Troubleshooting
Error Messages
207 FADC CAL
Slope derivation failed during FADC log expand offset
calibration.
This error applies only to EC-series analyzers and
E-series analyzers with fast ADC (Option 007).
250 OUTOF RG
ADC input is outside of ADC range.
251 NO IRQ
Microprocessor not receiving interrupt from ADC.
LO and RF Hardware/Firmware Failures (300 to 399)
YTO Loop Errors (300 to 301)
These errors often require troubleshooting the A14
frequency control assembly (synthesizer section) or the
ADC circuits.
300 YTO UNLK
YTO (1st LO) phase locked loop is unlocked. The ADC
measures YTO_ERR voltage under phase-lock
condition.
301 YTO UNLK
YTO (1st LO) phase locked loop is unlocked. Same as
ERR 300 except ERR 301 is set if the voltage is outside
certain limits.
YTO Loop Errors (317 to 320)
These messages indicate that the YTO main coil coarse
DAC (ERR 317) or fine DAC (ERR 318) is at its limit. If
error codes 300 or 301 are not present, a hardware
problem exists in the YTO loop but the loop can still
acquire lock. Refer to Chapter 11 to troubleshoot the
YTO PLL. The ADC circuit on the A3 interface
assembly may also cause this error.
317 FREQ ACC
Main coil coarse DAC at limit. The main coil coarse
DAC is set to bring YTO ERR close enough to 0 volts for
the main coil fine DAC to bring YTO ERR to exactly
0 volts. ERR 317 is set if the main coil coarse DAC is set
to one of its limits before bringing YTO ERR close
enough to 0 volts.
318 FREQ ACC
Main coil fine DAC at limit. The main coil fine DAC is
set to bring YTO ERR to 0 volts after the main coil
coarse DAC has brought YTO ERR close to 0 volts.
ERR 318 is set if the main coil fine DAC is set to one of
its limits before bringing YTO ERR to 0 volts.
319 WARN COA
YTO coarse tune DAC near limit.
320 WARN FIN
YTO fine tune DAC near limit.