Electrics and electronics are not the same thing. I was addressing Martyn and his specific question. No offence intended, but I doubt many RGIs can look at a circuit board and work out the purpose of each semiconductor and diode and perhaps build a new circuit board that works without using manufacturer's parts (would be illegal to install, but that's not my point here). Perhaps you can, Harvest, but no one I have met in the flesh.
I'm now confused though, because Martyn himself was talking about electronics and now he says he is an electrical engineer, which could just mean he's a sparky.