Icom IC-746 (IC 746 IC746) transceiver mods reviews software and diagrams

   
 
ham | what is new | links
 Welcome to Www.Hampedia.net  submit to reddit
20 November 2019, 1:28 UTC 


SDR


ELAD
SDRplay

Transceivers


Kenwood
Midland
Yaesu
Alinco
Icom
Other

Antennas


M2
Par
Gap
Sirio
Araki
Maco
Nil-Jon
Maldol
Comet
Hustler
Nagoya
Watson
Hy-Gain
Dressler
Cue Dee
Solarcon
Diamond
Cushcraft
Quicksilver
Moonraker

Power supplies


Powerbox
Kenwood
Diamond
Samlex
Mascot
Daiwa
Yaesu
Alinco
Icom
H&H

Rotators


M2
CDE
Yaesu
Create
Kenpro

Antenna tuners


MFJ
LDG
SGC
Icom
Yaesu
Mizuho
Dentron
Kenwood
Sommerkamp
Barker & Williamson

Repeaters


GME
Icom
Zodiac
Kenwood

Transverters


Microwave Modules
Tokyo Hy-Power
SSB Electronics
Tecnostudi
Kenwood
Yaesu
Minix

Meters


Diamond
Comet
Bird
MFJ

Ham resources


Propagation:
  Sporadic E skip (Es)
  Backscatter
  Tropo
  Meteor Scatter (MS)
  F2 Skip
  Aurora
  Trans-equatorial scatter (TE)
  Lightning scatter (LS)

Icom IC-746 (IC 746 IC746)
IC-746
Programming interface schematics for Icom:
Programming software for Icom IC-746 (IC 746 IC746) :
PDF User Manual for Icom IC-746 (IC 746 IC746) :
PDF Adjusments Procedures Manual with schematics for Icom IC-746 (IC 746 IC746) :
Schematics for Icom IC-746 (IC 746 IC746) :

Mods for Icom IC-746 (IC 746 IC746) :
    Icom IC-746 (IC 746 IC746) improved AGC and weak signal volume
    Icom IC-746 (IC 746 IC746) adjustment point
    Icom IC-746 (IC 746 IC746) TX/RX frequency mod IC746 JA ver.
    Icom IC-746 (IC 746 IC746) Electronic Keyer Speed Modification
    Icom IC-746 (IC 746 IC746) Loss of tx power all bands
    Icom IC-746 (IC 746 IC746) Using 500Hz filters on SSB for Dig Modes
    Icom IC-746 (IC 746 IC746) Backlight
    Icom IC-746 (IC 746 IC746) modulation on AM
    Icom IC-746 (IC 746 IC746) (USA models) All Band TX Modification
    Icom IC-746 (IC 746 IC746) Schematic for ICOM CI-V Option
    Icom IC-746 (IC 746 IC746) Monitor Audio Output Too Low
    Icom IC-746 (IC 746 IC746) Solutions for chip blowing with mPC
    Icom IC-746 (IC 746 IC746) Power mod
    Icom IC-746 (IC 746 IC746) Separating the Tx and Rx lines
    Icom IC-746 (IC 746 IC746) Extended RX/TX
    Icom IC-746 (IC 746 IC746) Modification
    Icom IC-746 (IC 746 IC746) out of range TX/RX

Icom IC-746 (IC 746 IC746) technical specifications :  Icom IC-746 (IC 746 IC746) technical specifications



Icom IC-746 (IC 746 IC746) Loss of tx power all bands

DC to LIGHT op amp, uPD1678 (actually a MMIC), located on the RF unit (bottom side of radio, rear left, remove shield cover) will shut down ALL tx on ALL bands when it fails. I have replaced three of them so far.

MMIC is the "i1678", actually a uPD1678. Input is pin 1, lower right, and output is pin 5, upper left pin on the SMD chip. Check in FM mode any HF band, using RF probe, should have very small sig on pin 1 and very large (>.6volts DC) on the RF probe when applied to pin 5. When chip fails, pin 5 goes to very near 0 millivolts on the RF probe.

uPD1678, icom number is 1110001890, lists about 10 bucks or less. Changing this chip requires proficiency in surface mount desoldering, and anti-static protection measures.

CB Equipment


President
Midland
Uniden
Zodiac

 Power amplifiers


Beko
Icom
Alinco
Drake
Yaesu
Daiwa
Collins
Kenwood
DanAmps
Ameritron
Autophon
Eto/Alpha
Command Technologies
E.F.Johnson
Dentron Radio Co.

FRS/GMRS


Bell
GPX
ENC
Tekk
Icom
Sony
Alinco
Drake
Cobra
Maxon
Vertex
Conair
Uniden
Jenson
Ranger
Midland
Whistler
Magnum
Unwired
Coleman
Motorola
Audiovox
Memorex
Columbia
Samsung
Standard
Kenwood
Cherokee
Panasonic
Freetalker
Vtech Vtalk
RadioShack
Fanon Courier
Sharper Image
General Electric
Oregon Scientific

PMR446


Sommerkamp
FreeQuency
Goodmans
Kenwood
Lafayette
President
Binatone
Motorola
Multicom
Albrecht
Maycom
Topcom
Xtreme
Ondico
Telcom
Maxon
Vertex
Zodiac
Yaesu
Cobra
Alinco
Icom
Alan
ITT