E8257D/67D, E8663D PSG Signal Generators Service Guide 107TroubleshootingTroubleshooting Unlocks— If all signals are present:1. Turn off the signal generator and disconnect the power cord.2. Replace the A5 Sampler.— If a signal is not present for a connector listed above:1. Troubleshoot back to that connector’s assembly.2. If the signal is not present at the assembly:a. Turn off the signal generator and disconnect thepower cord.b. Replace the assembly.3. Reinstall the A5 Sampler.4. Replace W11.625 Internal Pulse Generator UnlockA 625 internal pulse generator unlocked message indicates a failure on theA11 Pulse/Analog Modulation Generator.— Replace the A11 Pulse/Analog Modulation Generator.626 Internal Mod Source UnlockA 626 Internal Mod Source Unlock error message indicates a problem with thedigital 10 MHz signal to the A11 Pulse/Analog Modulation Generator. Thiserror message is turned on if the signal generator is in phase modulation modeand there is a problem with the 10 MHz digital signal to the in phase clock.1. Set the signal generator to phase modulation mode.2. Measure pin P131–91. The waveform is not a sine wave, but more like adistorted pulse waveform >2 Vpp.3. If the waveform is present, replace the A11 Pulse/Analog ModulationGenerator.4. If the signal is not present, replace the A7 Reference.left mmx connector approximately 850 MHz >–6 dBm from A6 Frac–NConnector Signal
