BillB wrote: James Perrett wrote:
BillB wrote:II was surprised at the 'any polarity' part.
I guess they've gone to the expense of putting a bridge rectifier on the power input.
My rudimentary understanding of electronics made me think that a bridge rectifier was for converting AC to DC. Didn't know one could be used for converting +/- DC to +DC.
Clever stuff. Why doesn't everyone do it? - no more fried DC inputs after wrong polarity 'experiments' :beamup:
The answer you might know. cost. Yes a wee 1 amp bridge rectifier might be less than 50p but the beancounters always have an eye on the competition.
There is also a technical reason, you are putting extra diode volt drops in the DC feed which means the upstream voltage has to be a bit higher and more volts means more money...again!
Hi Hugh, we crossed qwertys with the same story. Not sure I agree with "Most people are smart..."!!