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INTRODUCTION

This service manual describes the latest service information
for the IC-746PRO HF/VHF TRANSCEIVER.

DANGER

NEVER connect the transceiver to an AC outlet or to a DC
power supply that uses more than 16 V.  This will ruin the
transceiver.

DO NOT expose the transceiver to rain, snow or any liquids.

DO NOT reverse the polarities of the power supply when
connecting the transceiver.

DO NOT apply an RF signal of more than 20 dBm (100 mW)
to the antenna connector. This could damage the transceiv-
er’s front end.

ORDERING PARTS

Be sure to include the following four points when ordering
replacement parts:

1. 10-digit order numbers
2. Component part number and name
3. Equipment model name and unit name
4. Quantity required

<SAMPLE ORDER>

1110003870 S.IC

NJM2058M-T1

IC-746PRO MAIN UNIT

5 pieces

8810005770 Screw BiH M3 

× 

8 ZK

IC-746PRO  Top cover

10 pieces

Addresses are provided on the inside back cover for your
convenience.

REPAIR NOTES

1. Make sure a problem is internal before disassembling the

transceiver.

2.

DO NOT

open the transceiver until the transceiver is 

disconnected from its power source.

3.

DO NOT

force any of the variable components.  Turn

them slowly and smoothly.

4.

DO NOT

short any circuits or electronic parts.  An insu-

lated tuning tool 

MUST

be used for all adjustments.

5.

DO NOT

keep power ON for a long time when the trans-

ceiver is defective.

6.

DO NOT

transmit power into a signal generator or a

sweep generator.

7.

ALWAYS

connect a 50 dB to 60 dB attenuator between

the transceiver and a deviation meter or spectrum ana-
lyzer when using such test equipment.

8.

READ

the instructions of test equipment thoroughly

before connecting equipment to the transceiver.

To upgrade quality, any electrical or mechanical parts and
internal circuits are subject to change without notice or
obligation.

Summary of Contents for IC-746PRO

Page 1: ...HF VHF TRANSCEIVER i746PRO SERVICE MANUAL ...

Page 2: ...05770 Screw BiH M3 8 ZK IC 746PRO Top cover 10 pieces Addresses are provided on the inside back cover for your convenience REPAIR NOTES 1 Make sure a problem is internal before disassembling the transceiver 2 DO NOT open the transceiver until the transceiver is disconnected from its power source 3 DO NOT force any of the variable components Turn them slowly and smoothly 4 DO NOT short any circuits...

Page 3: ...NDUCTOR INFORMATION SECTION 9 BOARD LAYOUTS 9 1 S LOGIC BOARD 9 1 9 2 DISPLAY BOARD 9 3 9 3 TEN KEY BOARD 9 5 9 4 MODE BOARD 9 5 9 5 PHONE BOARD 9 5 9 6 RIT BOARD 9 5 9 7 PBT BOARD 9 5 9 8 MIC BOARD 9 6 9 9 MAIN UNIT 9 7 9 10 DSP UNIT 9 9 9 11 RF UNIT 9 11 9 12 CTRL UNIT 9 13 9 13 TUNER UNIT 9 15 9 14 PA UNIT 9 17 9 15 FILTER UNIT 9 19 9 16 DRV BOARD 9 19 9 17 VARISTOR A BOARD 9 19 9 18 VARISTOR B...

Page 4: ... suppression More than 55 dB TX variable range 9 99 kHz Mic connector 8 pin connector 600 Ω ELE KEY connector 3 conductor 6 35 d mm 1 4 KEY connector 3 conductor 6 35 d mm 1 4 SEND connector Phono RCA ALC connector Phono RCA RECEIVER Receive system Triple conversion superheterodyne Intermediate frequencies 1st IF freq 64 455 MHz 2nd IF freq 455 kHz 3rd IF freq 36 kHz Sensitivity typical SSB CW RTT...

Page 5: ...to S LOGIC board J303 DS1002 9 2 DISPLAY BOARD TOP VIEW 9 3 ...

Page 6: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 13811HZ C1 2002 Icom Inc ...

Page 7: ..._sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf Icom IC 746 PRO _sm02 pdf ...

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