Modifications for the Icom IC-746

Picture(s) of Icom - IC-746

19-07-1998 IC-746 out of range TX/RX (1 Kbytes)
11-12-1999 IC-746 Modification (2 Kbytes)
25-10-2000 Extended RX/TX for IC-746 (0 Kbytes)
02-12-2000 Separating the Tx and Rx lines (1 Kbytes)
02-07-2001 Power mod for the IC-746 (0 Kbytes)
20-10-2001 Solutions for chip blowing with mPC (33 Kbytes)
13-01-2002 Monitor Audio Output Too Low
25-01-2002 Schematic for ICOM CI-V Option (16 Kbytes)

Monitor Audio Output Too Low
Author: - heloxx@hotmail.com.MODIFICATION.NET


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.