Flex Disc options for the HP 9825

curiousmarc3 at gmail.com curiousmarc3 at gmail.com
Sat Aug 13 05:15:13 CDT 2016

Thanks for the info. Any schematics of the modification?

> On Aug 13, 2016, at 2:37 AM, Rik Bos <hp-fix at xs4all.nl> wrote:
> For what it's worth a small warning about the HP 9825 series computers.
> The power supply doesn't have a crowbar(over voltage protection), so a
> transistor failure in the Psu can be catastrophic.
> On the other hand the two 9835's I have, which uses the same form factor and
> almost the same power supply layout are HP modified with crowbars added.
> It seems to be good practice to add some ov-protection to the HP 9825 supply
> because the switching transistor and 723 voltage regulators don't have the
> eternal life.
> And there no certain prediction in how they fail, short or open circuit, I
> found out the hard way several years ago.
> -Rik

More information about the cctalk mailing list