Day Brown wrote in a message to Roy J. Tellason:
 DB>  On 10-31-97 Roy J. Tellason wrote to Day Brown... 
 RJ> There was also the UPS that would fit in the space where  
 RJ> your normal power supply went,  and I'm sure that something  
 RJ> like that could be adapted for external battery power. 
 DB> Well, maybe. lemme know if you see it again Roy. 
Ok,  though I don't read the literature anywhere near as much as I used to...
 DB> The UPS designs I've seen are kinda pricey.  It is a lot 
 DB> cheaper to make the power supply part if the input voltage is 
 DB> 48 v DC,  which is commonly used as battery backup in Telco and 
 DB> other types of critical commercial/business applications. 
Hmm.
 DB> And, then by locking in the user to some higher voltage, they 
 DB> try  to lock him into using their *proprietary* batteries... in 
 DB> case you want more backup time in a small, or home office. 
I can see a somewhat higher voltage,  it being easier to design stuff that 
will handle a fair amount of power without getting into absurd current 
levels.  It can get kinda hard to solder battery cable sized wire to some of 
those transistor terminals,  too...    
Some of the forklift batteries I've seen are 48 volts.  I'll bet they'd run a 
computer for a *LONG* time!
email: roy.j.tellason%tanstaaf@frackit.com 
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