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

   
 
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05 May 2024, 12:22 UTC 


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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) Monitor Audio Output Too Low

The monitor function on the IC-746 tends to have low output compared to receiver AF volume, therefore in order to listen to yourself, you have to increase the volume. When the PTT is released back to receive mode, the AF setting nearly blows your speaker or your headphones.

If the monitor audio output is too low on your ICOM 746, you can add 4.7K resistor in parallel with R1087. This brings up the gain of IC1082 to a more reasonable level that can still be controlled by the monitor level function but with plenty more gain.

Technical Notes:

These SMDs are located in the Main Board. You will probably need a service manual to locate these parts on the main board. Adding modifications to these very small parts requires some skill and a good magnifier together with the appropriate tools. A 1/8 Watt resistor will be suitable for this modification, but still require some precision.