sorry for the confusion, Like i say i have added a new aerial not the window one, this new aerial is a dab aerial, i have rune the cable to the back of the radio, the aerial cable connects to the fakra connection not the iso, also the new aerial is amplified so i have brought the 12v cable to the back of the unit, the problem i have is dont know where to connect the new 12v cable from the new aerial, do i splice it into the exsisting radio plug or take it back to the fuse box, this is not a aftermarket radio its a sony 2011 ford sony with dab. So all i really need a a ignition fed 12v supply, not a constant 12v supply as the battery will go flat when i leave it, hope i made it clearer, thank you once again , kind regards mick