Nothing wrong with it and no reason to go inside, owner bought it to replace the standard "wall-wart" for some kit, it is stylish, slim and glossy black , so more elegant.
As very slim , presuumably switch mode. You set the voltage between 15V and
21V. 1amp rating, by use of a matchstick into recessed holes for set plus adjust , voltage shown on an illuminated watch size LCD display , display is on all the time. Presumably voltage stored in an EEprom or similar. Just curious, is there any likelihood/known history of mains-bourne glitches corrupting such an eeprom in close proximity to mains wiring, ie set for 15V and unknowingly jumping to 21V ?
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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