• Two CR2032 batteries read 5.97V but Kitchen Scales show 'LO'

    From Andrew@Andrew97d@btinternet.com to uk.d-i-y on Thu Jan 1 21:44:41 2026
    From Newsgroup: uk.d-i-y

    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew



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  • From Spike@aero.spike@mail.com to uk.d-i-y on Thu Jan 1 21:53:56 2026
    From Newsgroup: uk.d-i-y

    Andrew <Andrew97d@btinternet.com> wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew

    Hysteresis or viscoelastic effects on the strain-gauge mounting changing
    with the increasing age of the scales, or the current cooler temperatures affecting the same?

    Aging batteries affected by the lower temperatures?

    Combination of both?
    --
    Spike
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  • From John R Walliker@jrwalliker@gmail.com to uk.d-i-y on Thu Jan 1 22:48:03 2026
    From Newsgroup: uk.d-i-y

    On 01/01/2026 21:53, Spike wrote:
    Andrew <Andrew97d@btinternet.com> wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew

    Hysteresis or viscoelastic effects on the strain-gauge mounting changing
    with the increasing age of the scales, or the current cooler temperatures affecting the same?

    Aging batteries affected by the lower temperatures?

    Combination of both?

    Electrode passivation in the batteries. Try shorting them for
    a couple of seconds and retesting.
    John

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  • From nib@news@ingram-bromley.co.uk to uk.d-i-y on Fri Jan 2 10:16:13 2026
    From Newsgroup: uk.d-i-y

    On 2026-01-01 21:44, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew




    I usually find brand new CR2032s reading about 3.2V open circuit. By the
    time they are down to 3.0V they are getting quite old?

    nib
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  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Fri Jan 2 10:55:55 2026
    From Newsgroup: uk.d-i-y

    On 01/01/2026 21:44, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew



    I bought a new radio moyse and fitted the old mouse batteries to it.
    After a month it started drifting. The mouse pointer would move without
    any movement of the mouse.
    I measured the battery. 0.9V...

    Easy enough to change the batteries.

    My kitchen scales are old and mechanical. I picked them up at an
    'antique' shop for a fiver..
    --
    rCLThe ultimate result of shielding men from the effects of folly is to
    fill the world with fools.rCY

    Herbert Spencer

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  • From Tricky Dicky@tricky.dicky@sky.com to uk.d-i-y on Fri Jan 2 11:30:58 2026
    From Newsgroup: uk.d-i-y

    Andrew <Andrew97d@btinternet.com> wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew





    In my experience many batteries can register close to their stated voltage
    when measured open circuit but will show a rapid drop off in voltage as
    soon a load is applied a drop off in open circuit voltage only occurring
    when when the battery is almost exhausted.

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  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Fri Jan 2 11:56:19 2026
    From Newsgroup: uk.d-i-y

    On 02/01/2026 11:30, Tricky Dicky wrote:
    In my experience many batteries can register close to their stated voltage when measured open circuit but will show a rapid drop off in voltage as
    soon a load is applied a drop off in open circuit voltage only occurring
    when when the battery is almost exhausted.

    Rise in internal resistance. Absolutely typical of a car battery. They
    test by applying a small load and extrapolating to how much current will
    drop the volts to some arbitrary value like 6V, that wont turn the starter.

    Cold Cranking Amps. Needs to be about 500 IIRC
    --
    rCLIt is not the truth of Marxism that explains the willingness of intellectuals to believe it, but the power that it confers on
    intellectuals, in their attempts to control the world. And since...it is futile to reason someone out of a thing that he was not reasoned into,
    we can conclude that Marxism owes its remarkable power to survive every criticism to the fact that it is not a truth-directed but a
    power-directed system of thought.rCY
    Sir Roger Scruton

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  • From Sam Plusnet@not@home.com to uk.d-i-y on Fri Jan 2 19:24:42 2026
    From Newsgroup: uk.d-i-y

    On 02/01/2026 10:16, nib wrote:
    On 2026-01-01 21:44, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew




    I usually find brand new CR2032s reading about 3.2V open circuit. By the time they are down to 3.0V they are getting quite old?

    The CR2032 in my car keyfob last one hell of a long time.
    So much so that when the battery died a couple of days ago I had no recollection on how to open the thing up. I had to watch a Youtube
    video to remind me of the steps.
    That's the second time I've replaced the battery and we've had the car
    for 8 years.
    --
    Sam Plusnet
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Sam Plusnet@not@home.com to uk.d-i-y on Fri Jan 2 19:27:53 2026
    From Newsgroup: uk.d-i-y

    On 02/01/2026 10:16, nib wrote:
    On 2026-01-01 21:44, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew




    I usually find brand new CR2032s reading about 3.2V open circuit. By the time they are down to 3.0V they are getting quite old?

    The CR2032 in my car keyfob last one hell of a long time.
    So much so that when the battery died a couple of days ago I had no recollection on how to open the thing up. I had to watch a Youtube
    video to remind me of the steps.
    That's the second time I've replaced the battery and we've had the car
    for 8 years.
    --
    Sam Plusnet
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Paul@nospam@needed.invalid to uk.d-i-y on Fri Jan 2 14:56:39 2026
    From Newsgroup: uk.d-i-y

    On Thu, 1/1/2026 4:44 PM, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew

    Needs an impedance test.

    https://data.energizer.com/pdfs/cr2032.pdf

    Nominal Voltage: 3.0V # Not really, it can be higher than that no-load. 3.2 to 3.3V.

    Pulse Drain: 2 seconds X 12 times/day
    400 ohms
    ~6.8 mA @ 2.7V # Voltage drops to 2.7V when you draw 6.8mA
    # And that is when the battery is new.

    # The other test they do is with 15,000 ohms as a resistor load.

    By pulling datasheets from some other companies, additional
    test cases may be extracted.

    Normally, there isn't a lot of "other chemistry" behaviors, such as
    charging up an onboard capacitor to near ideal voltage. Usually a CR2032
    sags in both voltage and increased internal impedance, and once approaching
    the knee voltage, a CR2032 is usually flat in an additional 3 weeks or so (at 10uA).

    *******

    The shelf life on CR2032 is only ten years.

    The LR2032 are rechargeable, and last for about
    three days, and are intended for mains powered
    devices that need a bit of backup for settings
    when mains go off. When you find these in devices,
    you may not place the alter-ego in the slot. You cannot replace
    a CR2032 with an LR2032, nor replace an LR2032 (in a laptop)
    with a CR2032.

    CR2032 are not a rechargeable cell type, and truth be told,
    their allowed charging current is 0 uA. However, for real
    world circuits, and using Schottky diodes, some amount of
    charging-leakage current needs an allowance, and consequently
    the datasheet was "adjusted" to make certain applications
    of CR2032 possible. But a CR2032 can explode if abused (at much higher abuse-currents), a 1uA current flow makes this mostly unlikely
    (the gas would likely escape as soon as it is made).

    A digital watch would draw 2uA from a CR2032.
    A computer draws 10uA from a CR2032 (RTC and CMOS RAM locations as a load).

    While they can be pulsed at larger currents than the datasheet suggests, they're not going to last all that long while doing that.

    Paul


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  • From Abandoned Trolley@that.bloke@microsoft.com to uk.d-i-y on Sat Jan 3 08:25:37 2026
    From Newsgroup: uk.d-i-y


    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?
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  • From nib@news@ingram-bromley.co.uk to uk.d-i-y on Sat Jan 3 09:18:22 2026
    From Newsgroup: uk.d-i-y

    On 2026-01-03 08:25, Abandoned Trolley wrote:

    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?

    I have one - displays the time in binary on LEDs!

    nib
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  • From Paul@nospam@needed.invalid to uk.d-i-y on Sat Jan 3 04:27:30 2026
    From Newsgroup: uk.d-i-y

    On Sat, 1/3/2026 3:25 AM, Abandoned Trolley wrote:

    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?

    I have a watch that runs off two penlight cells.

    You've heard of bodges I suppose :-)

    The RTC in a computer, uses the same circuit as a digital
    watch, and a crystal at 32768Hz (inaudible). The digital
    watch draws 2uA doing that, the computer draws 10uA.
    That's one reason the battery is larger.

    An older Mac used a cylindrical battery for its timepiece,
    but the thing still did not run forever. You might get a dozen to fifteen
    years out of that setup. It's unclear why they thought such a power
    source was required for the job.

    Before the CR2032 era came along, the timepiece was a taller epoxy package Dallas Semi time piece. The battery was underneath the epoxy out of sight.
    (You were given no way to access the battery and change it.)
    And the battery in that was a bit smaller than a CR2032. And when the
    battery was worn out, you had to take a Dremel and grind off some epoxy
    and make bodge connections to power it and keep it going. Using whatever battery you thought appropriate.

    https://www.ardent-tool.com/misc/Dallas_Rework.html

    Paul
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  • From Joe@joe@jretrading.com to uk.d-i-y on Sat Jan 3 09:47:12 2026
    From Newsgroup: uk.d-i-y

    On Sat, 3 Jan 2026 08:25:37 +0000
    Abandoned Trolley <that.bloke@microsoft.com> wrote:

    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?

    Mine takes a CR2025. It is advertised as having a 10 year battery life,
    and I've changed the battery twice in mine, which is rather more than
    20 years old i.e. the battery lasts longer than its quoted shelf life.
    --
    Joe

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  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sat Jan 3 10:31:06 2026
    From Newsgroup: uk.d-i-y

    In message <10jane5$14oph$1@dont-email.me>, at 04:27:30 on Sat, 3 Jan
    2026, Paul <nospam@needed.invalid> remarked:

    The RTC in a computer, uses the same circuit as a digital
    watch, and a crystal at 32768Hz (inaudible). The digital
    watch draws 2uA doing that, the computer draws 10uA.
    That's one reason the battery is larger.

    An older Mac used a cylindrical battery for its timepiece,
    but the thing still did not run forever. You might get a dozen to fifteen >years out of that setup. It's unclear why they thought such a power
    source was required for the job.

    Before the CR2032 era came along, the timepiece was a taller epoxy package >Dallas Semi time piece. The battery was underneath the epoxy out of sight. >(You were given no way to access the battery and change it.)
    And the battery in that was a bit smaller than a CR2032. And when the
    battery was worn out, you had to take a Dremel and grind off some epoxy
    and make bodge connections to power it and keep it going. Using whatever >battery you thought appropriate.

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a
    holder in the plastic lid). Keep it simple, stupid.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From RJH@patchmoney@gmx.com to uk.d-i-y on Sat Jan 3 11:41:21 2026
    From Newsgroup: uk.d-i-y

    On 3 Jan 2026 at 08:25:37 GMT, Abandoned Trolley wrote:


    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?

    I've a Lidl watch that takes one. And if there's space, so it should.

    My pet hate is devices that use AAAs when AAs could easily have been used in the case space.
    --
    Cheers, Rob, Sheffield UK
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From NY@me@privacy.net to uk.d-i-y on Sat Jan 3 12:04:41 2026
    From Newsgroup: uk.d-i-y

    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10 years
    or so, and is kept topped up all the time the computer is powered on
    (either booted up for an old-style PSU or trickle charged from a modern
    PSU with standby power), so it only needs to power the RTC for the
    fairly short times that the PC is off or unplugged from the mains?
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Chris Green@cl@isbd.net to uk.d-i-y on Sat Jan 3 12:31:44 2026
    From Newsgroup: uk.d-i-y

    NY <me@privacy.net> wrote:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10 years
    or so, and is kept topped up all the time the computer is powered on
    (either booted up for an old-style PSU or trickle charged from a modern
    PSU with standby power), so it only needs to power the RTC for the
    fairly short times that the PC is off or unplugged from the mains?

    Some motherboards I've used in the past (like 20 ore more years ago)
    had small NiCd cells for the RTC.

    However all modern ones seem to have non-rechargeable button cells.
    --
    Chris Green
    -+
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From jkn@jkn+nin@nicorp.co.uk to uk.d-i-y on Sat Jan 3 12:49:07 2026
    From Newsgroup: uk.d-i-y

    On 03/01/2026 12:04, NY wrote:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in
    a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10 years
    or so, and is kept topped up all the time the computer is powered on
    (either booted up for an old-style PSU or trickle charged from a modern
    PSU with standby power), so it only needs to power the RTC for the
    fairly short times that the PC is off or unplugged from the mains?

    Cost, I would think

    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sat Jan 3 13:25:36 2026
    From Newsgroup: uk.d-i-y

    In message <10jb0kq$17bvh$1@dont-email.me>, at 12:04:41 on Sat, 3 Jan
    2026, NY <me@privacy.net> remarked:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in
    a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10
    years or so, and is kept topped up all the time the computer is powered
    on (either booted up for an old-style PSU or trickle charged from a
    modern PSU with standby power), so it only needs to power the RTC for
    the fairly short times that the PC is off or unplugged from the mains?

    Mainly because they never expected the machines to have an operating
    life of even five years, let alone ten.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sat Jan 3 13:27:27 2026
    From Newsgroup: uk.d-i-y

    In message <10jav91$16voi$1@dont-email.me>, at 11:41:21 on Sat, 3 Jan
    2026, RJH <patchmoney@gmx.com> remarked:
    On 3 Jan 2026 at 08:25:37 GMT, Abandoned Trolley wrote:


    A digital watch would draw 2uA from a CR2032.


    What sort of watch takes a CR2032 ?

    I've a Lidl watch that takes one. And if there's space, so it should.

    My pet hate is devices that use AAAs when AAs could easily have been used in >the case space.

    There were many things wrong with the Apple Newton, but crippling the
    battery life by using AAAs was one of the most egregious. Especially as
    that bit of the design was old-tech, not new-tech.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Sat Jan 3 13:43:21 2026
    From Newsgroup: uk.d-i-y

    On 03/01/2026 12:04, NY wrote:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in
    a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10 years
    or so, and is kept topped up all the time the computer is powered on
    (either booted up for an old-style PSU or trickle charged from a modern
    PSU with standby power), so it only needs to power the RTC for the
    fairly short times that the PC is off or unplugged from the mains?

    Many did and the extruded residue destroyed many motherboards.
    --
    rCLPuritanism: The haunting fear that someone, somewhere, may be happy.rCY

    H.L. Mencken, A Mencken Chrestomathy

    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Paul@nospam@needed.invalid to uk.d-i-y on Sat Jan 3 12:22:29 2026
    From Newsgroup: uk.d-i-y

    On Sat, 1/3/2026 7:31 AM, Chris Green wrote:
    NY <me@privacy.net> wrote:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a >>> holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity
    rechargeable battery so it never runs out of charge, even after 10 years
    or so, and is kept topped up all the time the computer is powered on
    (either booted up for an old-style PSU or trickle charged from a modern
    PSU with standby power), so it only needs to power the RTC for the
    fairly short times that the PC is off or unplugged from the mains?

    Some motherboards I've used in the past (like 20 ore more years ago)
    had small NiCd cells for the RTC.

    However all modern ones seem to have non-rechargeable button cells.


    Some laptops use LR2032, having maybe 3 day capacity for RTC timekeeping.

    Even those cells eventually wear out, and need replacement
    with the same part number "LR2032". The CR2032 is not to be
    placed in such a laptop.

    If the battery pack in the laptop, is left in place in the
    cavity, then the laptop battery keeps the LR2032 charged, and
    you can have accurate time for months. It is when you unplug
    the laptop, remove the removable battery pack, that the
    LR2032 runs down and accurate time is lost.

    As a result, some laptops do have the desired ("rechargeable") scheme.

    But since the two cells types, depend on the correct support circuit
    being on the motherboard, the end-user cannot simply slap in
    either of the two and get correct operation. Only the designed
    type, may be placed in the machine. A CR2032 replaced with a CR2032.

    *******

    NiCd used in this way, are notorious for spilling electrolyte
    on the PCB and eating the copper tracks. You do not want
    NiCd in there. Not really. And if an alkaline circuit setup
    was used (four AA), those had better not be Duracell brand
    (which corrode and leak, damaging battery cell contacts).
    Some other alkaline brands, die with a little more grace and dignity.
    And don't damage your goods.

    Paul
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Paul@nospam@needed.invalid to uk.d-i-y on Sat Jan 3 13:05:31 2026
    From Newsgroup: uk.d-i-y

    On Sat, 1/3/2026 8:43 AM, The Natural Philosopher wrote:
    On 03/01/2026 12:04, NY wrote:
    On 03/01/2026 10:31, Roland Perry wrote:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a holder in the plastic lid). Keep it simple, stupid.

    I've always wondered why computers didn't use a low-capacity rechargeable battery so it never runs out of charge, even after 10 years or so, and is kept topped up all the time the computer is powered on (either booted up for an old-style PSU or trickle charged from a modern PSU with standby power), so it only needs to power the RTC for the fairly short times that the PC is off or unplugged from the mains?

    Many did and the extruded residue destroyed many motherboards.

    For people who restore old pinball machines, the NiCd corrosion damage
    is a curse.

    The "high score" was stored in a Mostek RAM chip and the RAM had battery-backing with NiCd. This allowed a pinball machine to be
    moved from one arcade to another, without losing the high score.
    The particular RAM used, had pretty decent performance for the
    time, only sucking microamps when not being clocked. The same
    chip was used in a number of designs (copy-cat design). But the
    design of the NiCd portion, left a lot to be desired. They would
    trickle charge the NiCd string, causing them to ooze. Nobody knew
    how to make a precision charger for the job.

    Some modern PCB fabrications, have decent passivation over the copper,
    to provide a measure of protection to corrosion. The PCBs back
    in the early pinball era, would not have all the cleverness some
    of the modern PCBs have. For example, microwave oven PCBs can
    have conformal coatings on them, to protect from cooking moisture
    and popcorn salt.

    The PCBs I used to make in the kitchen sink (no, you DONT pour the
    ferric chloride down the sink!), had no protection and were bare
    copper. Just corrosion from elements in the air, doomed such
    PCBs to a ten year max lifetime. You don't even need NiCd juice
    to ruin an amateur PCB. I used to "draw" designs on double sided
    copper blanks, using "india ink" and a suitable pen. The largest
    double sided PCB I ever made, was the PCB for a keyboard. It
    took several hours, with a strong light source, to get the keyboard
    key contact prongs, to align with the bloody holes. But I got that
    sucker in there and soldered, and it worked. The keyboard does not
    use a conventional interface, and the signals travel over a ribbon
    cable.

    I used to buy a tube of same-sized drill bits, because of the number
    of bits snapped off while hand-drilling the blank PCB first with
    the hole pattern (I didn't even own a mini-drill-press). Drawing
    the etch pattern on the PCB, comes after you drill the pilot holes.
    The home method does not have PTH, so the soldering aspect is yet
    another adventure. The drill bits are fancy enough, they come
    with names like "#58". Rather than adverts quoting actual diameter.
    The chuck on a hand drill does not close tightly enough to hold
    those bits, so they have to be custom-wrapped with the old cello
    tape, and "formed" in the chuck, until the bit was centered.

    The stupid stuff... we used to do in the name of science :-)

    Paul


    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Andrew@Andrew97d@btinternet.com to uk.d-i-y on Sat Jan 3 20:05:43 2026
    From Newsgroup: uk.d-i-y

    On 03/01/2026 10:31, Roland Perry wrote:
    In message <10jane5$14oph$1@dont-email.me>, at 04:27:30 on Sat, 3 Jan
    2026, Paul <nospam@needed.invalid> remarked:

    The RTC in a computer, uses the same circuit as a digital
    watch, and a crystal at 32768Hz (inaudible). The digital
    watch draws 2uA doing that, the computer draws 10uA.
    That's one reason the battery is larger.

    An older Mac used a cylindrical battery for its timepiece,
    but the thing still did not run forever. You might get a dozen to fifteen
    years out of that setup. It's unclear why they thought such a power
    source was required for the job.

    Before the CR2032 era came along, the timepiece was a taller epoxy
    package
    Dallas Semi time piece. The battery was underneath the epoxy out of
    sight.
    (You were given no way to access the battery and change it.)
    And the battery in that was a bit smaller than a CR2032. And when the
    battery was worn out, you had to take a Dremel and grind off some epoxy
    and make bodge connections to power it and keep it going. Using whatever
    battery you thought appropriate.

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of
    those :-). 3 inch floppy !!!!
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Bob Eager@news0009@eager.cx to uk.d-i-y on Sat Jan 3 20:41:01 2026
    From Newsgroup: uk.d-i-y

    On Sat, 03 Jan 2026 20:05:43 +0000, Andrew wrote:

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a
    holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of
    those . 3 inch floppy !!!!

    Your memory is failing. The PC1512 used 5.25 inch floppies (360kB, also
    later 1.2MB).

    You are thinking of the PCW8256.
    --
    My posts are my copyright and if @diy_forums or Home Owners' Hub
    wish to copy them they can pay me -u1 a message.
    Use the BIG mirror service in the UK: http://www.mirrorservice.org
    *lightning surge protection* - a w_tom conductor
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Pamela@pamela.private.mailbox@gmail.com to uk.d-i-y on Sat Jan 3 21:42:57 2026
    From Newsgroup: uk.d-i-y

    On 22:48 1 Jan 2026, John R Walliker said:
    On 01/01/2026 21:53, Spike wrote:
    Andrew <Andrew97d@btinternet.com> wrote:


    I haven't used my kitchen scales for a while but had a need to over
    Christmas when I noticed that the reading wasn't stable. After
    showing, say 155 grammes, the reading slowly drifted down quite a
    bit.

    Batteries had not leaked (and not Duracell !) but I cleaned them
    and the contacts and tried again, with the same effect.

    Each battery reads 3V, and both together read 5.97V which seems to
    suggest that they are OK for a device with miniscule current drain.
    They are over 15 years old.

    There is a tool stand at the local wednesday market that sells
    Renata 2032 batteries and this is a very good make (swiss). So I'll
    get a fresh pair, but since the existing ones read the correct
    voltage what could be the problem ?.

    Andrew

    Hysteresis or viscoelastic effects on the strain-gauge mounting
    changing with the increasing age of the scales, or the current
    cooler temperatures affecting the same?

    Aging batteries affected by the lower temperatures?

    Combination of both?

    Electrode passivation in the batteries. Try shorting them for a
    couple of seconds and retesting. John

    Is that safe?
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sun Jan 4 09:49:27 2026
    From Newsgroup: uk.d-i-y

    In message <10jbsqn$1ghtt$1@dont-email.me>, at 20:05:43 on Sat, 3 Jan
    2026, Andrew <Andrew97d@btinternet.com> remarked:

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells
    (in a holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of
    those :-). 3 inch floppy !!!!

    Rubbish!!! The PC1512 had 5.25" floppies, just like the IBM PC, and
    while we were at it we made it twice as powerful as the machine being
    cloned.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sun Jan 4 09:54:05 2026
    From Newsgroup: uk.d-i-y

    In message <mrtd6tFdmetU2@mid.individual.net>, at 20:41:01 on Sat, 3 Jan
    2026, Bob Eager <news0009@eager.cx> remarked:
    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells (in a
    holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of
    those . 3 inch floppy !!!!

    Your memory is failing. The PC1512 used 5.25 inch floppies (360kB, also
    later 1.2MB).

    You are thinking of the PCW8256.

    The PCW8256 did indeed have 3" floppies [180kB per side, or 720kB double-sided], partly for backwards compatibility with the CPC series,
    but mainly because it would be two years in the future before 3.5"
    floppies were available as a mass market product, and of course 5.25"
    floppies would have added about 50% to the build cost and 25% to the
    machine's case size.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Bob Eager@news0009@eager.cx to uk.d-i-y on Sun Jan 4 10:03:15 2026
    From Newsgroup: uk.d-i-y

    On Sun, 04 Jan 2026 09:49:27 +0000, Roland Perry wrote:

    In message <10jbsqn$1ghtt$1@dont-email.me>, at 20:05:43 on Sat, 3 Jan
    2026, Andrew <Andrew97d@btinternet.com> remarked:

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells
    (in a holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of >>those :-). 3 inch floppy !!!!

    Rubbish!!! The PC1512 had 5.25" floppies, just like the IBM PC, and
    while we were at it we made it twice as powerful as the machine being
    cloned.

    I was wondering if you'd jump in, but I did correct him earlier! And
    thought of you...
    --
    My posts are my copyright and if @diy_forums or Home Owners' Hub
    wish to copy them they can pay me -u1 a message.
    Use the BIG mirror service in the UK: http://www.mirrorservice.org
    *lightning surge protection* - a w_tom conductor
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Roland Perry@roland@perry.co.uk to uk.d-i-y on Sun Jan 4 10:19:21 2026
    From Newsgroup: uk.d-i-y

    In message <mrus73FdmetU3@mid.individual.net>, at 10:03:15 on Sun, 4 Jan
    2026, Bob Eager <news0009@eager.cx> remarked:
    On Sun, 04 Jan 2026 09:49:27 +0000, Roland Perry wrote:

    In message <10jbsqn$1ghtt$1@dont-email.me>, at 20:05:43 on Sat, 3 Jan
    2026, Andrew <Andrew97d@btinternet.com> remarked:

    Meanwhile, the RTC battery in an Amstrad PC1512 was four AA cells
    (in a holder in the plastic lid). Keep it simple, stupid.

    Your computing needs must have been very simple to make do with one of >>>those :-). 3 inch floppy !!!!

    Rubbish!!! The PC1512 had 5.25" floppies, just like the IBM PC, and
    while we were at it we made it twice as powerful as the machine being
    cloned.

    I was wondering if you'd jump in, but I did correct him earlier! And
    thought of you...

    Of course, the "Computing Need" is quite disjoint from the size of the
    media, because 3" floppies are entirely plug-compatible with 5.25"
    [another reason for choosing them, because the quirky 3.5" at the time, weren't] so you can crunch numbers just as easily with a genuine IBM PCC
    that has a 3" floppy, as one with the 5.25"

    And people did that, so they could develop software for the CPC/PCW on
    an IBM PC, then trivially transfer to 3" media to use.
    --
    Roland Perry
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Andrew@Andrew97d@btinternet.com to uk.d-i-y on Thu Jan 8 21:33:43 2026
    From Newsgroup: uk.d-i-y

    On 02/01/2026 19:56, Paul wrote:
    On Thu, 1/1/2026 4:44 PM, Andrew wrote:
    I haven't used my kitchen scales for a while but had a
    need to over Christmas when I noticed that the reading
    wasn't stable. After showing, say 155 grammes, the
    reading slowly drifted down quite a bit.

    Batteries had not leaked (and not Duracell !) but I
    cleaned them and the contacts and tried again, with
    the same effect.

    Each battery reads 3V, and both together read 5.97V
    which seems to suggest that they are OK for a device
    with miniscule current drain. They are over 15 years
    old.

    There is a tool stand at the local wednesday market
    that sells Renata 2032 batteries and this is a very
    good make (swiss). So I'll get a fresh pair, but
    since the existing ones read the correct voltage what
    could be the problem ?.

    Andrew

    Needs an impedance test.

    https://data.energizer.com/pdfs/cr2032.pdf

    Nominal Voltage: 3.0V # Not really, it can be higher than that no-load. 3.2 to 3.3V.

    Pulse Drain: 2 seconds X 12 times/day
    400 ohms
    ~6.8 mA @ 2.7V # Voltage drops to 2.7V when you draw 6.8mA
    # And that is when the battery is new.

    # The other test they do is with 15,000 ohms as a resistor load.

    By pulling datasheets from some other companies, additional
    test cases may be extracted.

    Normally, there isn't a lot of "other chemistry" behaviors, such as
    charging up an onboard capacitor to near ideal voltage. Usually a CR2032
    sags in both voltage and increased internal impedance, and once approaching the knee voltage, a CR2032 is usually flat in an additional 3 weeks or so (at 10uA).

    *******

    The shelf life on CR2032 is only ten years.

    The LR2032 are rechargeable, and last for about
    three days, and are intended for mains powered
    devices that need a bit of backup for settings
    when mains go off. When you find these in devices,
    you may not place the alter-ego in the slot. You cannot replace
    a CR2032 with an LR2032, nor replace an LR2032 (in a laptop)
    with a CR2032.

    CR2032 are not a rechargeable cell type, and truth be told,
    their allowed charging current is 0 uA. However, for real
    world circuits, and using Schottky diodes, some amount of
    charging-leakage current needs an allowance, and consequently
    the datasheet was "adjusted" to make certain applications
    of CR2032 possible. But a CR2032 can explode if abused (at much higher abuse-currents), a 1uA current flow makes this mostly unlikely
    (the gas would likely escape as soon as it is made).

    A digital watch would draw 2uA from a CR2032.
    A computer draws 10uA from a CR2032 (RTC and CMOS RAM locations as a load).

    While they can be pulsed at larger currents than the datasheet suggests, they're not going to last all that long while doing that.

    Paul



    Well I bought a couple of Renata 2032's at Worthing Wednesday market
    but when I got home, I noticed 'made in PRC' on the back. :-(
    I always used Renata silver oxide SR44's in my film cameras before,
    because they were Swiss made.

    Seems that most button cells are now made in China (limited adherence
    to pesky pollution regulations and other obstacles to mass cheap
    production).

    Anyway, Kitchen scales are much better, still a slight drift, but
    for kitchen stuff not an issue.

    Andrew
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From RJH@patchmoney@gmx.com to uk.d-i-y on Fri Jan 9 09:11:41 2026
    From Newsgroup: uk.d-i-y

    On 8 Jan 2026 at 21:33:43 GMT, Andrew wrote:

    Well I bought a couple of Renata 2032's at Worthing Wednesday market
    but when I got home, I noticed 'made in PRC' on the back. :-(
    I always used Renata silver oxide SR44's in my film cameras before,
    because they were Swiss made.

    Seems that most button cells are now made in China (limited adherence
    to pesky pollution regulations and other obstacles to mass cheap
    production).

    GP and LIDL both seem to be PRC. Just noticed the Lidl 2032s only have a 3
    year shelf life. 10 years for the GPs.

    Reviews at:

    https://batteryreview.wordpress.com/cr2032-rankings/
    --
    Cheers, Rob, Sheffield UK
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From jkn@jkn+nin@nicorp.co.uk to uk.d-i-y on Fri Jan 9 10:24:28 2026
    From Newsgroup: uk.d-i-y

    On 09/01/2026 09:11, RJH wrote:
    On 8 Jan 2026 at 21:33:43 GMT, Andrew wrote:

    Well I bought a couple of Renata 2032's at Worthing Wednesday market
    but when I got home, I noticed 'made in PRC' on the back. :-(
    I always used Renata silver oxide SR44's in my film cameras before,
    because they were Swiss made.

    Seems that most button cells are now made in China (limited adherence
    to pesky pollution regulations and other obstacles to mass cheap
    production).

    GP and LIDL both seem to be PRC. Just noticed the Lidl 2032s only have a 3 year shelf life. 10 years for the GPs.

    Reviews at:

    https://batteryreview.wordpress.com/cr2032-rankings/

    Thanks for the link. Ikea Plattboj appear to have been discontinued, sadly

    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Andy Burns@usenet@andyburns.uk to uk.d-i-y on Fri Jan 9 11:14:40 2026
    From Newsgroup: uk.d-i-y

    Andrew wrote:

    Seems that most button cells are now made in China

    From my ragtag assortment ...

    Boots : japan
    Hitachi-Maxell : japan
    Panasonic : indonesia
    Amazon : china
    Energiser : china
    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From Andy Burns@usenet@andyburns.uk to uk.d-i-y on Fri Jan 9 18:13:38 2026
    From Newsgroup: uk.d-i-y

    jkn wrote:

    Ikea Plattboj appear to have been discontinued, sadly

    Their original smarthome devices used CR2032 but are now on "last chance
    to buy" status, the newer devices use AAA, so presumably Ikea no longer
    sell anything that takes coin cells?
    --- Synchronet 3.21a-Linux NewsLink 1.2