Date   : Mon, 30 May 2005 13:35:48 +0100
From   : Philip Pemberton <philpem@...>
Subject: Re: Slightly off-topic ... How do I replace an A3000 CMOS battery?

In message <429ABFE1.6020909@...>
          Richard Hobbis <rhobbis@...> wrote:

> I think the battery is soldered in place, but which bit?
> Is it the two dimples on top or does the whole 'button' plus the two 
> contacts come off?

The entire battery comes off - it's soldered to the bottom of the board. Cut
the tags (but don't cut the battery open!), then desolder them.

That motherboard looks pretty badly mangled. Get some white vinegar on there
pronto (the electrolyte in the battery is alkaline - the acidic vinegar
neutralises it). Scrub with a fibreglass or brass brush to get the corrosion
off, then clean up with more vinegar and follow up with some pure water. Use
some pure isopropyl alcohol (90% or so) to draw out the water.
Make sure you get ALL the corrosion off, otherwise it'll continue eating away
at the board over time.

I would be VERY surprised if that board still worked. Those vias look like
they're utterly wrecked.

> Is it just a matter of melting the solder in the dimples for instance?

No, they're spot welded on.

> Do I need to solder in the new one?

Yes.

Later.
-- 
Phil.                              | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@...                        | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/          | 48xCD, ARCINv6c IDE, SCSI
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