Icom IC-T90A manual Logic unit, Bottom View, SP1, Sql Ptt

Page 45

LOGIC unit

• BOTTOM VIEW

W2 (L)

SP1

W2 (L)

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

40			2
39			1
40	SQL	J1	PTT
40		J1	2

GND +10V

WXALT

INTSP

WFM

PDAUL

PLSTB

CK

TXC

AM

DASTB

IOSTB

DIUD

DATA

SD

REMO

R3C

DICK

V2C

V3C

VSFT

V1C

EXTM

NOISE

MUTE

BEEP

VCC

HV

DETO

VOLC

+3C +3

XMOD

AFV

PATMP

VMOD

GND

CHG

GND

GND

39

to AF unit J251

1

9 - 2

Image 45

Contents IC-t90a Ordering Parts IntroductionRepair Notes Sample OrderTable of Contents Specifications GeneralTransmitter Frequency MHz ReceiverWFM WFMLogic Unit Inside ViewsTop view Bottom viewAF Unit RF UnitTop view Bottom view Removing the rear panel Removing the AF unit Disassembly InstructionsReceiver Circuits Circuit Description4 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 APC Circuit RF Unit PLL CircuitsGeneral APC CircuitPLL Circuit VCO Divider Circuit VCO and RF Units2 R3V Switch IC AF Unit IC51 Power Supply CircuitsPort Allocations Voltage LineCPU Logic Unit IC1 Dtcs CtselLCD SEG35Operation on the Adjustment Mode Adjustment ProceduresOperation on the Output Power Adjustment PreparationConnection JIGAD-92SMA PLL Lock Trimmer AdjustmentVCO VoltageRF Unit VCO UnitL16 L456 L19Reference Adjustment Mode AdjustmentsDial FrequencyAdjustment Mode Adjustments PH ch 53.900 MHz Transmitting 8V 145 MHz Displayed frequency Connect an amme 45 a R325 Logic UnitR365 R326Ctcss Detector CoilTracking CP0 AF UnitIC151, pin 12 SD line L151Displayed frequency Connect a DC volt Maximum voltage Meter Adjustment Adjustment Condition OperationOrder Description Section Parts ListCoil Eljre 3N9Z-F Ceramic ECJ0EB1H681K Connector AXK6S30445P Ceramic ECJ0EC1H060C Encoder Trimmer Tantalum ECST1EY474R Ceramic ECJ0EC1H2R5B Mechanical Parts and Disassembly AccessoriesChassis Parts RF Unit Logic UnitChassis Parts AF Unit VCO UnitTransistors and Fets SEMI-CONDUCTOR InformationDiodes NameTOP View Board LayoutsMC1 Microphone DUPBottom View Logic unitSP1 SQL PTTRF Unit RF unit AF Unit VCO UnitEXT.SP EXT.MICREMOTO S253S252 Logic Unit Block DiagramLoop LPF HPF Drive BPF ANT FIL AMP Chassis11 1 Logic Unit Voltage DiagramIC5 2SK3476 11 2 RF UnitBU4094BCFV 11 3 AF UnitURL 32, Kamiminami, Hirano-ku, Osaka 547-0003, Japan