Re: Timemaster HO II Card

["Michael J. Mahon" <mjmahon@aol.com>]

John wrote:
> Thanks Michael.
>
> I was surprised it retained information. I thought the NiCd would be
> dead.
>
> Has any reader replaced these?
> If so: a) do you know of a souce for the 3.6 V Varta NiCd cell? b) has
> anyone tried 3 single cell NiCd's

Any combination of 3 NiCad cells of 100-500 mAH capacity will work
fine.  The issue is usually not finding cells (or batteries) but
finding a mechanical arrangement that is workable.

There are a lot of wireless phone 3-cell batteries that will do
the job, given a reasonable way to mount them.

The lower limit on battery capacity is set by the standby power
consumption of the clock chip, usually quite low.  The upper limit
is advisable to keep leakage much lower than the trickle charging
current, and, of course, to keep the physical size down.

NiCads should *not* be replaced with a non-rechargeable battery,
since the charging current can damage it.  An NiMH battery is an
alternative, but NiCads are preferred.

-michael

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