Hi @simonkemp ,
Does it work when batteries are installed in the radio ( 6 x R14/ UM2/ C Cell)?
If it works on battery power it may just be a problem with the AC input side of the power supply to the radio.
Don’t know the model but with other Philips radios of a similar type e.g. AZ102R there is a fuse on the AC input in the radio as well as diodes etc to convert the AC to the necessary DC voltage to operate the radio so maybe it is the same with your model.
Open the radio and then check if there is a fuse on the circuit board close to where the AC power cord plugs into the radio and use an Ohmmeter to check if it is OK or not.
If the fuse is OK then again use the Ohmmeter and do point to point testing from each leg of the AC input socket through the fuse and diodes etc to make sure that there is a path for the current.
Without a schematic this will not be easy but you can only try.
If it also doesn’t work on battery power then open the radio and check that the source switch (FM, Aux In, CD, Off switch) is working OK by using an Ohmmeter to check if the switch contacts are OK as it it the source switch that connects the power to the circuit.
Hopefully a start.