5V 3A PSU

Thermal fuses are allowed, and we now use the resetable type in the PSU1 transformer primary, but it was originally designed with a fuse and to change its rating now would involve it being retested at a cost of £10,000 minimum. It's a bit like a stranger inviting himself into your business and deciding he's profit sharing with you, except that in my case, and the addition of recurring fees, it would be something like 1000%. I think it is called bleeding you dry.

I am on the mailing list for a Cumbrian Accessories supplier and note in their latest catalogue they have a new multi-voltage, apparently universal power supply.

There are many brands incl GSP in the compatibility list.

It is relatively large and aroun £500 from memory, plus cables I suspect.

Looks like the new power supply has some competition, albeit at a price and size!

Not that it is any comfort but 'testing' costs are a fact of life for designers and manufacturers. I used to design in the gas industry and it was very galling to pay for the privilege of your design being tested by those who generally knew less about the subject that you did!

peterb wrote: I am afraid it is the price that is paid in an attempt to stop the cowboys and the opportunists, in the name of safety. Unfortunately it doesn't stop the criminals putting people at risk.

You will never stop the cowboys, opportunists and "crminals" in the hi-fi industry. There are too many people unwittingly supporting them by buying their products.

A few years ago I was told of a product in which the mains (live and neutral) was applied to a board where the spacing between solder pads was only suitable for signal level voltages. The designer obviously had no knowledge of creepage and clearance distances as required for the safety of the user or for the building in which it would be used (perhaps that could strike a chord with recent events?).

This designer and his company had a cult following and was definitely making good money out of his poor knowledge of customer safety.

But that seems to be the accepted practice these days. It is by luck alone that injury or worse does not happen with most of these products.