Icom IC-F21S service manual PLL Adjustment, PLL Lock, Main, Voltage

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5-2 PLL ADJUSTMENT

ADJUSTMENT		ADJUSTMENT CONDITIONS		MEASUREMENT		VALUE	ADJUSTMENT

			UNIT		LOCATION		UNIT	ADJUST
			UNIT		LOCATION		UNIT	ADJUST

PLL LOCK	1	• Operating frequency:	MAIN		Connect a digital multi	1.3 V	MAIN	C54
VOLTAGE		440.000 MHz			meter to check point
		• Receiving			LV.

	2	• Transmitting				1.3 V		C68

	3	• Operating frequency:				2.8–4.3 V		Verify
		470.000 MHz
		• Receiving

	4	• Transmitting				2.8–4.3 V

RF power meter

C54

PLL lock voltage adjustment (RX)

C68

PLL lock voltage adjustment (TX)

LV

PLL lock voltage check point

TOP VIEW

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Contents UHF FM Transceivers Introduction Ordering PartsRepair Notes Table of Contents ‘ Receiver Specifications‘ General ‘ TransmitterInside Views Main Unit TOP ViewBottom View Disassembly Instructions Removing the ChassisRemoving the Main Unit Receiver Circuits Circuit DescriptionTransmitter Circuits PLL Circuit PLL CircuitGeneral VCO CircuitPower Supply Circuits Voltage Line Port AllocationsPin Port Description Number 3 D/A Convertor IC IC9 Output Expander IC IC15Preparation Adjustment ProceduresGND Screen display exampeJIG cable SPEDC power cable connections DC Power Supply GNDConnection Voltage PLL AdjustmentPLL Lock MainSoftware Adjustment SQL SensitivitySquelch LevelSection Parts List UnitMain Unit Coil Eljfc R68M-F Array Electrolytic ECEV1CA470SP Connector Screw abbreviations B0, BT Self-tapping Mechanical Parts and DisassemblyAccessories Chassis PartsIC-F21S SEMI-CONDUCTOR Information Transistor and FET’SDiodes Main Unit Board LayoutsIC6 FT1SW-A and SW-B Units TOP View SW-A UnitSW-B Unit Bottom View SW-A Unit CBI0 CBI1 CBI2 CBI3GND Tled Rled VCC Volin Volout Charge Unit Parts ListDisassembly Information BC-146 Optional Desktop Charger InformationBoard Layout Voltage DiagramSW-A/SW-B Unit S1 Block Diagram2SC4215 O Voltage DiagramDTC144EU Section Voltage Diagram Q1 XP4216 SW-A UnitPage 32, Kamiminami, Hirano-ku, Osaka, 547-0003, Japan