Mods & Repairs

Icom 756 Pro3 Widebanded (UK Version)

Icom 756Pro3 WidebandedThere are plenty of articles telling you how to wideband the Icom 756 Pro 3 online. The radios do have different programming diodes installed for the various regions. Here I wideband a UK model.

A Word Of Warning, this fairly modern radio uses some extremely small components that require very delicate soldering skills. Please do not attempt this procedure unless you are absolutely sure you are competent to do so.

As with all mods of this nature, I’m not responsible if you break it – you have been warned.

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.

SMD diode sizeBefore 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. As you can see, the diode is only just over 1mm in length!

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.

Icom 756 Pro3 DSP UnitOnce you have the bottom cover removed you will see the DSP unit to the side. 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.

This is very important as it’s possible to install the unit the wrong way round when refitting it.

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 IC756 Pro 3 Diodes RemovedYou now have to locate and remove three diodes. The diodes that require removing for the UK radios are 3751, 3752 and 3754, circled in red in the photo.

You may need to open the picture to it’s full size to see exactly where these didoes were removed from.

You will notice that diode 3753 was left in place, and also that diodes 3755 and 3756 were not fitted at the factory in this model.

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 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.

A 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.

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.