I need a fairly large 12 volt DC power supply. About 8 amps peak. I
already have a regulated 5 amp one but that struggles for the purpose I
need. It needs to have an output of say between 12-14v at full load. And
be made from bits I have lying around. ;-)
I have two suitable transformers - both toroidal. One I'd guess is a low
volt lighting one marked 230v primary, 11.8v 100VA secondary. But with a
bridge rectifier and 30,000µF of smoothing gives 14.6 with a 55 watt load.
And somewhat over 17v with a small load.
The other transformer is an electronics type with two primaries marked
115v and two secondaries marked 12v 5 amp. Would that likely have any
I'd like to keep the max voltage within what would be expected in a car -
and the device takes a very small current with the 'engine' stopped.
The ideal would be to limit - rather than regulate - the peak voltage from
the first transformer - but most circuits I can find are actual
regulators. Any suggestions? Other than just use a car battery? ;-)
*I believe five out of four people have trouble with fractions. *
Dave Plowman firstname.lastname@example.org London SW
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