MIKE ROSS wrote in a message to Roy J. Tellason:

 MR> "Roy J. Tellason" bravely wrote to "Greg
Mayman" (11 May 04 
 MR> 12:06:48)  --- on the heady topic of "SILICON CHIP ON LINE"

 RJT> Greg Mayman wrote in a message to Roy J. Tellason:

 GM> I still have a 40m and an 80m that came out of my Compaq. I
 GM> _might_ use then one day to build a low end machine with some 486
 GM> m'boards I bought "as-new" that I haven't got around to using
 GM> yet...

 RJT> That sounds like that 386dx40 router/firewall I have going here.  The
 RJT> only problem with it is one of those soldered-in nicad batteries that
 RJT> doesn't seem to want to hold a charge any more.  I have a new one
 RJT> sitting here on my desk, but don't know if I want to bother sticking
 RJT> it in there or not.

 MR> The big problem changing those barrel batteries is that they are
 MR> often glued on top of a few circuit traces and the glue won't yield
 MR> easily making it dangerous to break a foil trace if forced too
 MR> much.

I haven't encountered that much in the way of glue with those that I've
removed from a bunch of boards here.  A lot of them were leaking.

 MR> You could always avoid the problem and use a 4 AA battery pack 
 MR> adaptor plugged into the external battery connector.

If there is a connector in there,  I don't recall.  And if I had such a
battery pack,  that is.  I know of one guy who got only about a year out of
one of those.  As it is,  I do have this nicad sitting here...

 MR> There is sometimes a jumper to set or remove to select the 
 MR> external battery but it is often marked on the silkscreen.

Yeah,  I know where to look.  I don't remember what's in there,  and would
have to open it up to see.

 MR> But you should *always* remove the old barrel because the leaking
 MR> electrolyte will dissolve the traces in the vicinity. If it can't
 MR> be removed then encase the barrel in a blob of silicon so it won't
 MR> leak. 

There's no such things as one that "can't" be removed.  At least
I've not had a problem in this regard yet!

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