- #Icom 756 pro ii alc how to#
- #Icom 756 pro ii alc install#
- #Icom 756 pro ii alc full size#
- #Icom 756 pro ii alc mods#
I assume you can run an external analog audio chain into that same audio port on the rear panel. This is a project in progress, but it seems worth a little effort given the large number of 756 series rigs out there, and the excellent AM receivers they have. These were created by using the line output of an FRG-7700 receiver, connected to the line input of one of the station computers, to record the Pro III with Adobe Audition as it sounds on the air. Two small audio samples are included here to help show the difference between the stock AM audio and the processed audio with the internal ALC defeated. This is pretty much a zero-effort-project if your digital interface is already installed! A number of mp3 files are included at the link to give some idea of how the Pro III behaves while transmitting in the AM mode with different EQ and compression settings. If you currently use your 756 Pro series rig for digital communications through one of the common computer interfaces, some easy improvements in AM performance can be made by using "real-time" computer processed audio that is generated by the free Voice Shaper software and then ported out from the computer sound card into the audio port in the back of the Pro III. This means that while you should be able to use the 60m band and the CB bands if you desire without any problems, any attempt to transmit at a frequency outside the allocated amateur bands may cause harm to, or failure of the transmitter RF power amplifier.Updated 6-26-2010: The link below has a few simple ideas about working around the aggressive ALC problem and the hard-coded DSP limitations of the 756 Pro III without any internal modifications to the rig itself. You will find the radio can now transmit wherever the VFO can go, and the band edge beeps are no longer enabled so you will need to make sure you stay within the bands.Ī word of warning the filters on the transmitter of this radio are designed to suppress signals outside of the amateur radio bands, and are very effective. Re-assembly is a reverse of the disassembly process, taking care not to bend any of the pins on the DSP unit and that you re-install it the correct way round – you did mark it as suggested, didn’t you? You will notice that diode 3753 was left in place, and also that diodes 37 were not fitted at the factory in this model.
#Icom 756 pro ii alc full size#
You may need to open the picture to it’s full size to see exactly where these didoes were removed from. The diodes that require removing for the UK radios are 3751, 37, circled in red in the photo. You now have to locate and remove three diodes. To remove the DSP unit pull it firmly straight up, be very careful not to pull at an angle as there are two multi pin connectors on the bottom, one at each end.
#Icom 756 pro ii alc install#
This is very important as it’s possible to install the unit the wrong way round when refitting it. Mark one end, you can see I used a red felt tip to mark the end of the unit which goes to the front of the radio. Once you have the bottom cover removed you will see the DSP unit to the side. ATU Emulator for Icom Radios: AA3Ms IC-735 CW Netting Mod: IC-2720 Adjustment Procedure: IC-7000 TVRO & MARS Mods: IC-703 60m Enabling Procedure: IC-703 Key Jack EMC HM-151 for icom 7100-wonderful Time Owned: 0 to 3 months. To begin the process, the bottom cover has to be removed, this can be achieved without removing the top cover by undoing the screws on the bottom and the two screws on either side and lifting it away.
As you can see, the diode is only just over 1mm in length! If you’re still thinking “I may have a go” – then by all means follow the procedure, but if at any point you feel a bit daunted, leave it to someone who is confident.īefore we start, to modify the Icom 756 Pro3, the procedure involves desoldering and removing small SMD diodes – this image shows a single diode on a tape measure.
#Icom 756 pro ii alc mods#
Please do not attempt this procedure unless you are absolutely sure you are competent to do so.Īs with all mods of this nature, I’m not responsible if you break it – you have been warned. Here I wideband a UK model.Ī Word Of Warning, this fairly modern radio uses some extremely small components that require very delicate soldering skills. The radios do have different programming diodes installed for the various regions.
#Icom 756 pro ii alc how to#
There are plenty of articles telling you how to wideband the Icom 756 Pro 3 online.