new battery blues

eh? ((no email))
Fri, 08 Oct 1993 08:50:26 HST

>From: MX%"" 7-OCT-1993 12:48:46.49
>Brad Corsello ( 3L Case Western Reserve Law School
>I've sent my batter back to NEC... now I'm having problems with my ultra.
>After about 20 minutes of use, the ultra intermittently "cuts out". If I'm
>using the modem, characters disappear from the incoming stream. The disk
>drive has problems, etc. I've noticed that while this is happening the
>"battery low" light flashes intermittently.
>Merely turning it off or even unplugging the AC power for a few seconds
>doesn't solve the problem. It has to sit unpowered for a few minutes
>before it goes back to normal.

This _may_not_ be a problem with the battery- sounds to me as if the external
power supply is being pulled low (ie "over-driven") by trying to charge the
new battery- it may be that the new batteries require a _long_ charge period
before using for the first time.

I would recommend leaving the battery/laptop/external power plugged into the
wall for at least 24hrs (maybe 48hrs?) before attempting to use the computer,
so that the battery is fully charged and not putting a strain on the external
power supply. Then try the computer both with and without the external supply.

The fact that the problem often shows up while using the internal modem makes
sense in this scenario, since the modem uses +/-12v, which would be the first
to go in the case of a power-supply "sag".

I doubt that this problem could cause any permanent damage, except in the case
where you are running RAMdisk compression (ie STAC), where you could lose data
in the case of intermittant power loss.

This is all just a guess, I can't check my prognosis as I bought a used UL
without battery or factory power supply. Those of you that have both might
want to check the voltages coming in from the external supply- you would need
to open the case and monitor voltages while the battery is charging (but with
the computer turned off) to see if the +12vdc in is being pulled low when the
battery is under "hard-charge".

By the way, if anyone else is thinking of dumping their new battery, please
consider me as a worthy recepient...


PS- I'm also looking for another 1mb RAM board, and/or a 2mb RAM board...