Replacing Assemblies - Disassembly and Reassembly 3Keysight 53147A/148A/149A Assembly Level Service Guide 93Removing the BumpersUse the following procedure to remove the front and rear protective bumpers:1 Remove the rear bumper by lifting the inner edge of the bumper away from theshroud near one corner at the top and one side and pulling that corner awayfrom the instrument. Repeat the process with the remaining corners until thebumper is free of the instrument.Figure 3-1 Removing the Bumpers2 Use the same procedure (as in Step 1) to remove the front bumper.OPTIONS001 Oven Time Base002 BatteryMain Power! !In or OutReference 10 MHz AuxiliaryAC POWER90-130 VAC 50/60/400 Hz190-230 VAC 50/60 HzFUSE1.5A T250VWARNING: To avoid electrical shock:Do not remove covers.No user serviceable parts inside.Refer all servicing to qualified personnel.RS- 232 GPIBCounter/ Power Meter/ DVMThis unit must be earth grounded. Made in U.S.A.of domestic and foreign contentPOWER METERPOWERGHz MHz kHz Hz20 GHz Counter/Power Meter/DVMMODIFYReset/LocalCalFactorFreqOffseMenuOn/OffEnterAvg+ / -FreqClearResolShiftCh 12Rel FreqOffsetAvg OnRel PwrOffsetdBdBmWattsmWuW%Ext RelErrorShiftHoldRate Rmt SRQStandbyCounterPowerMeterDVMRatePwrOffseDisplayPowerdBm/WStoreCalZeroOffsetOn/OffRelPwrDVM+–DAMAGE±60 VDCDisplayDVMPOWER METEROUTPUTPower Ref.1.00mW 50MHzINPUTDo NOTExceedSensorMax PowerCOUNTEROffsetOn/OffRel FreqChanSelectCOUNTERCHANNEL 110 Hz to 125 MHzDAMAGE+30 dBm1MCOUNTERCHANNEL 250MHzto 26.5GHz50DAMAGE+27 dBmGateNOTE The bumpers can be used to support and protect the instrument after the shroudis removed. Place both bumpers on their inner edges on your work surface, andthen place the instrument on top of them. The rear bumper can also serve as aholder for the instrument (once the bumper retainers are removed) when youneed to position it upright on either end.
