In article ,
mm wrote:
It seems I mailed home the powersupply cord and transformer for my IBM
ThinkPad 600E, instead of putting it in my suitcase.

So I need something to use until the package I mailed comes.

It says 15.5 to 17 volts DC, 56 watts, and I have a whole bunch of
possible adaptors to use, but if I have to make one from a transformer
and diodes, how much ripple filtering would I likely have to do to
simulate the original power supply. None at all? So many microfarads
worth before and so many after the diodes?

Be worth getting a learner book on electronics since things like values
needed for smoothing a given power will be explained. And the fact that
the DC voltage produced from an AC one depends on the type of
rectification too.
So if we look at the basics, 56 watts @ 17 volts is 3.3 amps.
Full wave rectification gives approx 1.4 x the AC supply
To smooth 4 amps needs 10,000 µF.

So a 12 volt 4 amp transformer, 4 amp bridge rectifier, and 10,000 µF
should give you 16.9 volts adequately smoothed.

--
*Black holes are where God divided by zero *

Dave Plowman London SW
To e-mail, change noise into sound.