IC-910H Service manual.pdf - N3UJJ

5-2 PLL ADJUSTMENTSADJUSTMENT30.2 MHzLEVELREFERENCEFREQUENCY144M LOCKVOLTAGE440M LOCKVOLTAGEMAIN BFOLEVELSUB BFOLEVEL11212312312ADJUSTMENT CONDITION• Display frequency: Any• Receiving• Display frequency: Any• ReceivingThis adjustment must be performedat 5 minutes later after power ON.• Display frequency: 173.9800 MHz• Mode: USB• Receiving• Display frequency: 136.0200 MHz• Receiving• Display frequency: 155.0000 MHz• Receiving• Display frequency: 479.9800 MHz• Mode: USB• Receiving• Display frequency: 420.0200 MHz• Receiving• Display frequency: 450.0000 MHz• Receiving• Display frequency: Any• Mode:USB• Receiving• Sub display freq. : Any• Mode:USB• ReceivingADJUSTMENTMEASUREMENTVALUEPOINTUNIT LOCATION UNIT ADJUSTPLLPLLPLLPLLPLLPLLConnect an RF voltmeteror spectramanalyzer to checkpoint J541.Connect an RF voltmeteror spectramanalyzer to checkpoint P551.Connect a frequencycounter to checkpoint P551.Connect a digitalmultimeter or oscilloscopeto check pointCP100.Connect an RF voltmeterto check pointP251.Connect a digitalmultimeter or oscilloscopeto check pointCP300.Connect an RF voltmeterto check pointP421.Connect an RF voltmeterto check pointP601.Connect an RF voltmeterto check pointP701.–10 dBm (or more than–11.5 dBm, when R570is in maximum position.)Maximum level(–13 dBm to –7dBm)60.400000 MHz2.7 V0.6 V to 1.6 V–10 dBm to –4 dBm3.4 V0.5 V to 1.5 V–16 dBm to –10 dBm–11 dBm to –5 dBm–11 dBm to –5 dBmPLLPLLPLLPLLPLLPLLR570Adjust insequenceL551, L552severaltimes.The trimmercapacitor ofX512.L193VerifyVerifyC402VerifyVerifyVerifyVerify5-3 FREQUENCY ADJUSTMENTADJUSTMENTFM TX-LOFREQUENCYADJUSTMENT CONDITION1 • Display frequency: AnyMAIN Connect a frequency• Mode: FMcounter to check• Disconnect P501, P502 (PA unit)point CP51.from J51 and J52 on the MAIN unit.• Apply no audio signals to [MIC]connector.• TransmittingAfter adjustment, connect P501, P502 (PA unit) to J51, J52 on the MAIN.ADJUSTMENTMEASUREMENTVALUEPOINTUNIT LOCATION UNIT ADJUST10.85000 MHz MAIN L2555 - 2From The N3UJJ.COM Document Library