Model 10617 Russell Hobbs toaster. The lever won't stay down, and the screws on the bottom look unusual. I searched on the net for this model, and (apart from everyone saying it stopped working because the lever won't stay down!) I found this: 'These are System Zero screws and they need a driver reference ZE3. RS components seem to be the only place to get these drivers. Their 542-122 driver bit works, confusingly they refer to it as size 1'
I have found System Zero screws online. and a set of drivers; but the review I found also says: 'The lever is held down by a magnet which relies on the electronic circuitry to operate. The wiring is complicated for such a simple device and there are two printed circuit boards. It does not seem possible to obtain a circuit or spares so repairing a fault would require reverse engineering the circuit, fault finding and replacing the individual faulty component.'
I don't understand the last part of that! but if I can't then mend the magnet ...
In the final analysis it will probably be best to bin the toaster and get a new one. Playing with electricity if you don't actually know what you are doing and understand why you are doing it, is very dangerous.
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