RPC battery.

[Dave Plowman (News)]

Looks like mine has failed. For the second time it has lost the date etc
at boot.

What's the best replacement and source these days?

--
*Ever stop to think and forget to start again?

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

[Chris Hughes]

In message <5927e66...@davenoise.co.uk>

"Dave Plowman (News)" <da...@davenoise.co.uk> wrote:

> Looks like mine has failed. For the second time it has lost the date etc
> at boot.

> What's the best replacement and source these days?

Probably CJE Micros



--
Chris Hughes

[Steve Fryatt]

On 5 May, Chris Hughes wrote in message
<9fc6e627...@mytarbis.plus.com>:

I thought the general consensus was a AA or AAA battery holder on flying
leads, well away from the PCB, and a suitable rechargable cell.

If you google this from several years ago, ISTR that I concluded that at the
charge currents used by the RPC, it was fine to continuously trickle-charge
NiMH cells (but whether I did that for AA and AAA cells is another matter).

--
Steve Fryatt - Leeds, England

http://www.stevefryatt.org.uk/

[Alan Griffin]

In article <5927e66...@davenoise.co.uk>,

Dave Plowman (News) <da...@davenoise.co.uk> wrote:

> Looks like mine has failed. For the second time it has lost the date
> etc at boot.

> What's the best replacement and source these days?

I just use an AA rechargeable battery with a lead connecting it to
where the old battery used to be.
Alan

[Dave]

In article <5927e8...@argonet.co.uk>,

Same here...
On my old SARPC (Purchased in early 1995 and still working) I removed the
battery from the MOBO many years ago, soldered in leads that come up to
the gulley at the front top of the two slices, fitted an AA battery holder
and a rechargeable battery... Never had any problems with it.

Dave

--

Dave Triffid

[Dave]

In article <5928036...@triffid.co.uk>,

Had a vague memory...
'Wunce upon a tyme...' There was an illustrated guide/howto on Bernard
Veasey's bapfish website about the CMOS battery replacement/moving.

Dave

--

Dave Triffid

[Stuart]

In article <mpro.qsnbkp01...@stevefryatt.org.uk>,

Steve Fryatt <ne...@stevefryatt.org.uk> wrote:
> > Probably CJE Micros

> I thought the general consensus was a AA or AAA battery holder on flying
> leads, well away from the PCB, and a suitable rechargable cell.

The only comment I would make is that it is a good idea to fully charge it
first in a standard charger or it will take forever at the low current
provided by the RPC

--
Stuart Winsor

Tools With A Mission
sending tools across the world
http://www.twam.co.uk/

[Chris Evans (CJE/4D)]

In article <mpro.qsnbkp01...@stevefryatt.org.uk>, Steve Fryatt

<URL:mailto:ne...@stevefryatt.org.uk> wrote:
> On 5 May, Chris Hughes wrote in message
> <9fc6e627...@mytarbis.plus.com>:
>
> > In message <5927e66...@davenoise.co.uk>
> > "Dave Plowman (News)" <da...@davenoise.co.uk> wrote:
> >
> > > Looks like mine has failed. For the second time it has lost the date etc
> > > at boot.

I hope I'm wrong but normally by the time the battery stops keeping date and
time, the horse has well an truly bolted with battery leakage having very
badly damaged the motherboard.
You might get away with a new plug in RTC see:
http://www.cjemicros.co.uk/blog/?m=201309

> > > What's the best replacement and source these days?
> >
> > Probably CJE Micros
>
> I thought the general consensus was a AA or AAA battery holder on flying
> leads, well away from the PCB, and a suitable rechargable cell.

We can supply 'remote batteries' or PCB attached!
As we are still occasionally finding working original batteries that havn't
leaked I suspect in another 20+ years time it won't be a battery fitted in
2021 that will be stopping the computer!

> If you google this from several years ago, ISTR that I concluded that at the
> charge currents used by the RPC, it was fine to continuously trickle-charge
> NiMH cells (but whether I did that for AA and AAA cells is another matter).

Chris Evans

--

****** IGEPv5: The fastest RISC OS computer so far! *******
------------ http://www.cjemicros.co.uk/igepv5 ------------
CJE Micro's 'Raspberry Pi & RISC OS Specialists'
Tel: +44 (0)1903 523222
ch...@cjemicros.co.uk http://www.cjemicros.co.uk/
Unit 16 Arunside Ind. Est., Fort Road, Littlehampton, W.Sussex BN17 7QU

Don't let the urgent things in life, crowd out the important things!

[Sebastian Barthel]

Am Wed, 05 May 2021 21:14:57 +0100 schrieb Dave:

> 'Wunce upon a tyme...' There was an illustrated guide/howto on Bernard
> Veasey's bapfish website

https://www.bapfish.org.uk/cmos.htm

and - until now - it stands the test of time.


For the "original oriented" user, there is also a NiMH replacement
Battery, wich is intended by Varta to replace the old batteries in place.
It's called

Varta CP 300H SLF

<https://www.voelkner.de/products/1109/Varta-CP-300H-SLF-Knopfzellen-
Akku-300H-NiMH-300-mAh-1.2V-1St..html>

( website for datasheets (UK) )


But probably its a much better idea to separate the battery from the
mainboard.


If Your battery has signs of leakage, its unavoidable to remove the
remnants from the mainboard. This is done by bathing this part of the
board in vinegard (2%-5%) and wash it twice with de-ionised water
afterwards. If its (really) dried it should be fit for another 125 years
or so.

Eventually it could be a good idea to take a photo of this part of the
board and show it to the people here or in the forum at iconbar or at
stardot.org.uk


If the mainboard is defected then the CJE replacements are very fine and
much easier to install, then a complete rearrangement and rebuilding of
the SMD structures in the area of the realtime clock chip. And probably
'cheaper' - but this depends.

[Stuart]

In article <s9fr5h$adf$1...@solani.org>,

Sebastian Barthel <nait...@freenet.de> wrote:

> But probably its a much better idea to separate the battery from the
> mainboard.

Everytime.

[Dave]

In article <593848ae...@argonet.co.uk>,

Stuart <Spa...@argonet.co.uk> wrote:
> In article <s9fr5h$adf$1...@solani.org>,
> Sebastian Barthel <nait...@freenet.de> wrote:

> > But probably its a much better idea to separate the battery from the
> > mainboard.

> Everytime.

At least on the Other side, on my Win PCs the CMOS batteries can just be
popped out of the holder and replaced, no soldering involved. :-)

Done that a few times over the years...

Dave

--

Dave Triffid