Re: Cable debate ...

In article <4de784d091jcgl@xxxxxxxxxxxxxxxxxx>, Jim Lesurf wrote:
> Just before Christmas a colleague brought me the electronics from his TT as
> it had stopped working. (Well regarded UK brand.)
>
> Examining it, and working out the circuit, worried me.
>
> There was no mains transformer, and no mains switch. The circuit was
> therefore live all the time the deck was plugged into the mains, regardless
> of the switches and indicators visible/useable on the deck.

There's a lot of dodgy design nowadays, the commonest manifestation being the
"lumpy mains plug" type of power supply with no switch, connected to the
equipment via one of those horrible little co-axial connectors with no
standardisation of physical size, voltage or polarity - if it even has a
polarity, because some of them are AC and some of them are DC. The only power
switch is in the low-voltage circuit, and being fitted to the equipment itself
probably gives the unsuspecting owner the comfortable feeling that when it's
switched off it's switched off.

Separate power supplies are so common nowadays, and almost unheard of when I
was young, that I wonder what can have changed? In reality, two boxes are more
expensive than one, considerably more ungainly, and with the huge variety of
power requirements a splendid opportunity for error, so there seems no
practical sense in not building the power supply into the equipment. My best
guess is that perhaps it is the result of some committee's misguided notion of
a safety feature, but does anybody know why?

Rod.

.

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