Re: IIGS - Clock/PRAM chip

[sundown@nwrain.net]

Thanks to everyone for taking the time to reply.

I tested the pins from the old battery while the battery replacement
were still hooked up and didn't get any voltage reading.  So I took
the battery replacement off and did some test on it.  The wire were
hooked up with the proper polarity and I received a good voltage
reading at the terminals.

I put them back on and tested the old battery pins again and still
did not get any voltage reading at all.  Before posting on here I
took the connectors off and put them back on again in hopes it
was a poor connection but it would never save the Time or PRAM.

I took them off again and tested the old battery pins again.  Finally
I did get a good voltage reading.  I can now turn the computer off,
wait a while, start it up and the TIME and PRAM are both saved.

So you were right!  It was a poor connection after all.  I know it
is possible the poor connection could be anywhere in the battery
replacement and just because it is working good now does not
mean it has been fixed.  Maybe it is just making a good connection
temporarily.  If it quits working again I will buy a brand new battery
replacement kit and install it.

Battery Replacement Kits can be purchased on line from
GSE-Reactive.com for around $7.00.

Thanks for taking the time to help.  Your advice did the job.

thanks again,
John Balgenorth


On Feb 15, 4:58 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
> sund...@nwrain.net wrote:
> > Thanks for the reply.  Yes the batteries are connected with
> > the right polarity.  The clock keeps good time but when I
> > turn off the computer it does not save the time or PRAM.
> > I am assuming the battery is used to save this info and
> > since they are connected properly and good it might be
> > the chip but I have no idea what is wrong.
>
> If it were the chip, then it wouldn't work when the computer
> is on either.  It has to be between the battery and the chip,
> and there are only some wire and a diode, or so.  The diode
> could be open, but that would be a rare failure.
>
> Look carefully at how the battery pack is attached to the
> board.  I'd be willing to bet that there's a bad connection.
>
> I don't know what kind of wire is used, but it's possible
> for the wire to be broken inside the insulation, particularly
> if it is thin solid wire.  Perhaps the solder joint is a "cold"
> joint, making bad electrical contact.  Perhaps it isn't soldered,
> just twisted--which is another place that the contact can be bad.
>
> Do you have a multi-tester or voltmeter?  Or an LED with a
> 470 Ohm resistor in series?  ;-)  If so, check for the presence
> of about +3.6v between the Vcc and Gnd pins of the clock/PRAM
> chip.
>
> -michael
>
> NadaNet networking for Apple II computers!
> Home page:  http://members.aol.com/MJMahon/
>
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