Table 10-4. Automatic Fault Isolation References (2 of 2)

Suspected Circuit Indicated by Automatic Fault Isolation

Check Offset Oscillator PLL

Check Offset Oscillator PLL Pre-Scaler

Check Offset Oscillator Pretune Circuitry

Check Offset Span Accuracy

Check Offset Oscillator Sweep/Hold Check Phase/Frequency Detector Check Path to Phase/Frequency Detector Check Roller Oscillator

Check Sampler Drive Output of A7 LODA Check Sampler IF

Check Sampler/Sampler IF Operation Check Span Attenuator

Check Sweep Generator

Check Sweep + Tune Multiplier

Check the 600 MHz Reference Loop Amplifier Check the YTO Loop

Check Transfer Oscillator

Check Transfer Oscillator PLL

Check Transfer Oscillator Pre-Scaler

Check Transfer Oscillator Pretune DAC

Check YTF Gain and Offset DACs

Check YTO FM Coil Driver

Check YTO FM Coil Driver and Main

Loop Error

Voltage Driver

Manual Procedure to Perform

Offset Oscillator PLL (steps 14-18)

Offset Oscillator PLL (steps 9-13)

Offset Oscillator PLL (steps 4-8)

First LO Span Problems 51 MHz (step 8) Offset Oscillator PLL (steps 20-23) Unlocked Reference PLL (steps 17-25’1 Unlocked Offset PLL (steps 3-7, 14-19)Unlocked YTO PLL (steps 14-18)Unlocked YTO PLL (steps 19-22)Unlocked YTO PLL (steps 23-27)Sampler and Sampler IF (steps l-15)

First LO Span Problems (All Spans) (steps 6-13)Sweep Generator Circuit

YTF Driver Circuit (steps 4-9)

Unlocked Reference PLL (steps 23-26)

Unlocked YTO PLL

Transfer Oscillator PLL (steps 1 and 2) Transfer Oscillator PLL (steps 15-16)Transfer Oscillator PLL (steps 11-14)Transfer Oscillator PLL (steps 11-14)Transfer Oscillator PLL (steps l-10)

First LO Span Problems (1 MHz to 20 MHz) (Step 6)

Unlocked YTO PLL (steps 35-40)

lo-10 Synthesizer Section