PLl

The PLLl Phase Lock Loop is unlocked. Items to check are:

nAlOAl - Check signal out at AlOAlJ3.

nAlOA2 - Check signal in at AlOA2J2.

nA10A3 - Check signal out at AlOA3J3.

nAlOA4 - Check signal out at AlOA4J2 and in at AlOA4J4.

PLL2

The PLL2 Phase Lock Loop is unlocked. Items to check are:

nAlOA5 - Check signal out at AlOA5J3.

nAlOA6 - Check 4 Det Out voltage at AlOA6TP7.

nAlOA7 - Check 500 kHz Reference at AlOA7TP5 and divided output at AlOA7TPl.

nAlOA8 - Check VCO Tune output current at AlOA8J2.

REF UNLOCK

The 10 MHz Reference Loop is unlocked. Items to check are:

nOVEN COLD indicator on. This is normal operation.

nCable W15 connected to rear-panel FREQ REFERENCE IN and OUT connectors. w Rear-Panel FREQ REFERENCE EXT/INT switch in proper position.

nA7Al and A7A2 - Check 10 MHz out at A7AlJ4.

YTO UNLOCK

The YTO Phase Lock Loop is unlocked. Items to check are: 1 A19 D/AConverter

nA20 Main Coil Driver

nA21 FM Coil Driver

nAll YTO Loop

nAl6 Scan Generator

M/N UNLOCK

The M/N Phase Lock Loop is unlocked. Items to check are:

nA7A3 - Check output at A7A3Jl.

nA7A4 - Check output at A7A4Jl.

Overall Troubleshooting 5