Copyright © 2001 Harmonic Inc. 5-3Maintenance5.2 Fan ReplacementShould a fan failure occur, disconnect the power cable and remove the four (4) phillips headscrews securing the fan to the module housing. Replace the failed fan unit with a new fan unit.Secure the new unit with the four (4) phillips head screws and reconnect the power cable.Figure 5-2 HOA 7000 Optical Amplifier Rear Panel Features5.3 In Case of ProblemsShould a problem occur, contact the Harmonic Customer Service Department at800-730-4099. A service technician will assist you in determining whether or not a fault existswith the unit. A Return Material Authorization (RMA) Number will be issued for any faultyunit that needs to be returned. Note this number on the shipping container and all correspon-dence.The return address is:Harmonic Inc.549 Baltic WaySunnyvale Ca. 95054Attention Customer ServiceRMA no._____________OPTICAL INPUTS:Interface to HLP4200 Platform