🚀 go-pugleaf

In article <36148@netnews.upenn.edu>, depolo@eniac.seas.upenn.edu (Jeff DePolo) writes:
> 
> I've been running in circles trying to find a source for high-current 
> transformers for a 120 AC to 13.8 DC supply.  The prices for most of
> the commercial supplies around (Astron, et. al.) seem ridiculously high.
> I'm hoping to find a transformer that will handle a solid 35A.
> 
> Any info would be greatly appreciated (except suggestions to roll my own) :-)
> 
> 								--- Jeff
> --
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>  Jeff DePolo  N3HBZ             Twisted Pair: (215) 386-7199                  
>  depolo@eniac.seas.upenn.edu    RF: 146.685- 442.70+ 144.455s (Philadelphia)  
>  University of Pennsylvania     Carrier Pigeon: 420 S. 42nd St. Phila PA 19104



What's wrong with a roll-your-own job?

You're talking about something in the 500+ watt range, which 
is *heavy* and to buy new could be on the expensive side.

But there are plenty of *big* transformers around practicallyl
for the taking --- usually with 120 v in, but sometimes with 
240 v primaries, which would be better.

So you find a roll of #12 or #10 insulated wire, start putting 
turns on the core where they can be fit, and before long you
have enough volts coming out --- then four (4) big but cheap
diodes bridged and you have what you wanted in the first place.
A *big* surplus condenser across the output and the ripple 
isn't too big, maybe.

Or maybe find a transformer from a junked welder or industrial
battery charger and you have it made.  Carrying the thing could
pose a problem.  *heavy*.

Or another wild but actually practical suggestion:  I've seen
*many* junked computers and major components thereof in scrap
yards, and many of these have multiple transformers in the 
range you note.  Those possessing them have no idea what they
are and emphatically don't want to know and are very happay to
sell by the pound.

Or, if you  want a pig, I have one for the taking, which with 
120 on the secondary might give you what you want on the primary.
Free for the taking on condition I don't get it back.

In summary, you ask for what can be very expensive if *bought* but
can be very *cheap* if scrounged.  Take your pick.

K3TX