Its not a set screw type – I just pulled the knobs off mine – If yours are stuck – there are two methods that I would try – first – a sharp rap on the middle of the knob inward – toward the back of the radio – this may break whatever corrosion is holding it on – not too hard – you don’t want to break the knob – and be very careful of the dial glass.
Next – take some strong string or butcher cord – wrap it around the back of the knob – and pull toward you with the free ends.
Removing the chassis screws and pushing the chassis toward the front of the cabinet may gain you a little more room to get the string behind the knob.
Good luck.

William – here in Ontario – its a very common radio – they must have been a big seller because there are a ton of them – in GE and RCA versions – as well as consoles – there were a few variations as far as tube complements and antennas – good performers – its been a few years since I did one – but from what I remember – biggest problems are push button assembly (contacts get dirty and oxidized)- rubberized wiring needs replacing, and resistors drifting off value.
Voltage is the same as US – it may have a 25 cycle transformer – but that won’t matter – they generally had physically smaller power transformers that tend to run hot – so you may want to reduce the line voltage by installing a bucking transformer – there are numerous articles
on the web about that.
It is a good radio for a new to intermediate restorer – good for learning a lot of things – and will test your ingenuity for operating and aligning out of the cabinet.