AF Unit, VCO Unit, Ext.Sp Ext.Micremoto | Icom IC-T90A specs

9 - 3 AF UNIT

• TOP VIEW

EXT.SP

EXT.MICREMOTO

J252J253

to S251

The combination of this page and the next page shows the unit layout in the same configuration as the actual P.C. Board.

DN	E	UP	VCO UNIT
4			VCO UNIT
4			• TOP VIEW
			• TOP VIEW

3

				1		2			to RF UNIT
				1		2	to RF UNIT		1	GND	1
							VSFT	8	1	V1
										V1
									J2	V2
						2	VMOD		J2	V2
					3	2	VMOD		8	VCO3
				40	3	1	GND			VCO3
							GND	J1		V3
							+10V			V3
				39			+10V			LO	6
to LOGIC unit J1				39			UNLK			LO	6
to LOGIC unit J1							UNLK
		GND	40				CK
39	GND	GND	40				PLSTB
39	GND	GND					PLSTB
	CHG	GND					REF	1
		PATMP					REF
		PATMP
	VMOD	XMOD
	AFV	+3							6
	+3C	+3							6
	+3C	DETO
	VOLC	DETO
	HV	VCC
	HV	MUTE
	BEEP	MUTE	J251
	NOISE	EXTM	J251
	NOISE	VSHFT
	V1C	V2C							1
	V3C	V2C							1
	V3C	SD
	REMO	SD
	REMO	R3C
	DICK	R3C
	DICK	DIUD
	DATA	DIUD
	DATA	DASTB
	IOSTB	TXC
	AM	TXC
	AM	WFM
	PDA/UL	WFM
	PDA/UL	PLSTB
	CK	WXALT
	INTSP	WXALT	2
1	GND	+10V	2	2
				1

9 - 5

Image 48

Icom IC-T90A manual AF Unit, VCO Unit, Ext.Sp Ext.Micremoto

Contents

IC-t90a Introduction Ordering PartsRepair Notes Sample Order Table of Contents Specifications GeneralTransmitter Receiver Frequency MHzWFM WFM Inside Views Logic UnitTop view Bottom view AF Unit RF UnitTop view Bottom view Disassembly Instructions Removing the rear panel Removing the AF unit Circuit Description Receiver Circuits 4 1ST Mixer and 1ST if Circuits RF, AF and VCO Units 5 2ND if and Demodulator Circuits AF UnitRF Circuit AF Amplifier Circuit AF Unit Squelch Circuitaf and Logic Units2ND if and Demodulator Circuit Transmitter Circuits PLL Circuits APC Circuit RF UnitGeneral APC Circuit VCO Divider Circuit VCO and RF Units PLL Circuit Power Supply Circuits 2 R3V Switch IC AF Unit IC51Port Allocations Voltage Line CPU Logic Unit IC1 Ctsel DtcsLCD SEG35 Adjustment Procedures Operation on the Adjustment ModeOperation on the Output Power Adjustment Preparation Connection JIGAD-92SMA Trimmer Adjustment PLL LockVCO Voltage VCO Unit RF UnitL16 L456 L19 Adjustment Mode Adjustments ReferenceDial Frequency Adjustment Mode Adjustments PH ch 53.900 MHz Transmitting 8V 145 MHz Displayed frequency Connect an amme 45 a Logic Unit R325R365 R326 Ctcss Detector CoilTracking AF Unit CP0IC151, pin 12 SD line L151 Displayed frequency Connect a DC volt Maximum voltage Adjustment Adjustment Condition Operation Meter Section Parts List Order Description Coil Eljre 3N9Z-F Ceramic ECJ0EB1H681K Connector AXK6S30445P Ceramic ECJ0EC1H060C Encoder Trimmer Tantalum ECST1EY474R Ceramic ECJ0EC1H2R5B Mechanical Parts and Disassembly AccessoriesChassis Parts Logic Unit RF UnitChassis Parts AF Unit VCO Unit SEMI-CONDUCTOR Information Transistors and FetsDiodes Name Board Layouts TOP ViewMC1 Microphone DUP Logic unit Bottom ViewSP1 SQL PTT RF Unit RF unit AF Unit VCO UnitEXT.SP EXT.MICREMOTO S253S252 Block Diagram Logic Unit Chassis Loop LPF HPF Drive BPF ANT FIL AMP Voltage Diagram 11 1 Logic Unit IC5 11 2 RF Unit 2SK3476 11 3 AF Unit BU4094BCFV URL 32, Kamiminami, Hirano-ku, Osaka 547-0003, Japan