Day Brown wrote in a message to Roy J. Tellason:
 DB>  On 10-27-97 Roy J. Tellason wrote to Jim Dunmyer... 
 RJ>  > What I don't understand is why there aren't power supplies that'll  
 RJ>  > work with a 12vdc input.  I have heard of such,  but they don't  
 RJ>  > appear to be out there at a reasonable cost,  compared to the  
 RJ>  > "standard" stuff... 
 RJ>  
 RJ>  JD> Why? I'd guess that there is only a very small demand for 
 RJ>  JD> such a thing.  
 RJ>  
 RJ> You're probably right,  that would seem to account for there not being 
 RJ> the  
 RJ> push toward lower prices that we see in so much else in  
 RJ> this computer stuff... 
 DB> They do make them for laptops; but they do not have grounded
 DB>  chassis, or good isolation between the inputs and outputs. 
 DB> I  build some from scratch that ain't so fussy, because as
 DB> you note,  there ain't much demand, so no vendors. 
I dunno about "no" vendors,  I do recall seeing that sort of thing out there 
at some point in time,  though it wasn't recently.
There was also the UPS that would fit in the space where your normal power 
supply went,  and I'm sure that something like that could be adapted for 
external battery power.
email: roy.j.tellason%tanstaaf@frackit.com 
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