Date   : Mon, 20 Jul 2009 09:32:17 +1200 (NZST)
From   : mjfoot@... (Michael Foot)
Subject: FileStore battery

Quoting Johan Heuseveldt <johan@...>:

> Hi,
> 
> On Sun 19 Jul, Andy Ford wrote:
> 
> > Having no FileStore (yet) unfortunately but without wanting to state
> the 
> > obvious, can you see any details on the existing battery regarding 
> > specification / voltage etc ? :)
> 
> According to the schematics: 3V6.
> It's a rechargeble battery, not a cell.

That's right. It's 3.6V.

> > Although your general idea (diode to prevent reverse charge, as I'm 
> > assuming its a Nicad type battery in the FileStore) and resistor is
> the 
> > way to go.
> 
> Not sure if the 4,5 volts are ok, although the diode will lower that.

With the diode and resistor, the reading is around 3.9V. I'm not sure if 
that's within tolerence or not. I could change the resister to a larger rating 
if need be.

I really wish Acorn had not soldered Nicads onto the motherboards of all it's 
machines. I have 40-50 machines here and it's taken me hours to open then all 
up and remove the batteries! Some I've been too late to prevent damage but 
mostly that damage was done by the time I got them. One A540 is too far gone I 
think. Shame as they are very rare in N.Z.!

Cheers,

Mike.

--
Michael Foot <mjfoot(at)paradise(dot)net(dot)nz> *
http://homepages.paradise.net.nz/mjfoot/
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