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

   
 
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20 November 2024, 2:22 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) Modification

Remove the twelve screws holding on the bottom cover.
With the Radio laying flat on it's top remove the bottom cover. Turn the radio so that the front panel is to your left and the antenna connectors are to your right. Locate the IC labeled "ICOM HD6433042SF".
About 3/4 of an inch to the right is a vertical row of diodes. The left hand column of diodes has 7 diodes (14 possible spaces). The right hand row is full with 14 diodes. Remove the diode in the 6th space from the top in the left hand column. DO NOT remove anything from the right hand column. This should get you TX from about 100KHZ to 60MHZ and 118MHZ to 176MMZ.

Do this totally at your own risk. Never, ever transmit out of the ham bands or your privileges..

Additional information.

After having put a forward reading watt meter on my 746 i have found that there is NO loss of power due to this mod. It is still putting out the full 100 watts when you have a good match (5-100 on SSB and FM and 2-40 on AM).

I have also discovered that the TX was NOT opened up above 54MHz to 60MHz the top end of the 6 meter band switch on the 746.

The only effect i have noticed is that sometimes while using the built in antenna tuner in manual tune the LCD display sometimes blinks or lights up with all functions showing or sometimes disappears below the line.
Also the band edge beep function option no longer works because with wide open TX there are no more band edges.
One must be carefull to stay within their operator band privileges.