I received a Screwfix triple detector (part number 16093) for Christmas.
This is suppose to detect pipes, joists and cables, however it's performance is abysmal. I can usually detect a cable in a block and plaster wall when I know it is there, however the setting is so fussy and varies so much across the width of a wall that I would have no confidence in the results if I didn't already know what was in the wall - i.e. it is going to be bugger all use for finding a random diagonal cable that a previous owner might have installed. Finding joists is a similarly hit and miss affair with it struggling to find the ceiling joists through a layer of artex and plasterboard..
Do I have a faulty one or is it just a crap model.