... When I startup I have a sad mac with 0000000F and 00000002 ...
$0F is a 68K exception, translating as a software error. In this case, stemming from unsuitable startup software, most probably. The
only completely free, complete System available for download after System 7.0 is, luckily for you, 7.5.3. Although it was first released as an update, Apple has made it available as a virtual Reference Release (an upgrade), which is normally available only by purchase. The updates have always been free, but incomplete unless you already have the relevant Reference Release to update from.
Go
here. Download to a PPC Mac by all means, but decompress/decode only after transfer to the target Mac into a single folder on the Desktop. To boot the Mac and transfer the 19-part image (on one floppy disk, 19 times, or on 19 floppies, as you please), you will need the Network floppy (cited above) to boot the Quadra, run Disk First Aid and re-install the hard disk driver.
When the Quadra can stand on its own feet in 7.5.3, you can download and install the
update to 7.5.5. It will repay you to prowl around that Apple downloads site for tips about 7.5.5 installation, and many other goodies.
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