Thanks for the reply,
I've seen this file but I'm a little lost.
Which version my machine has? 03.04 or 04.07 or 01.06? It is not clear from the instructions.
Looking at the furuno usa web site there is no software update listed under the RDP149 page.
Perhaps is identical with some other model? e.g. the GP1920
If it is, my serial number is 4346- does this mean this is a LED backlit model?
Furthermore i've looked at the GP1920 update instructions and I notice that my machine makes 2 beeps -one right after the other - when I press the on button. Not one beep as stated in the update instructions.