The old and badly built ones look like this on the outside:
They are really nice to use and I really like the bright display and general performance but the internal build quality is very poor.
I suspect that may be Thandar's influence on Thurlby.
Very possibly.
The other thing about the mk1 PL320 is that the LED display driver chip has been obsolete for many years and it is a known weak spot on the PSU.
I've been inside quite a few of them over the years at work when they go a bit dicky and the usual things I spot are loose screws in the termination blocks (probably work loose over the years and give intermittent connections) and the LED segments are playing up either due to poor/aged solder joints or because of a dead/dying LED driver chip.
Taking them apart further is not nice because the boards are all hard wired/soldered and the wires are quite stiff so you either have to unsolder each and every wire connection or try and bend the boards away from the hardware and try and swap out any broken parts. Not good...
The later ones are much better built than this
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