Sujet : Re: Booting a PowerWave 604|132.
De : <bp (at) *nospam* www.zefox.net>
Groupes : sci.electronics.repairDate : 29. Dec 2024, 18:55:30
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <vks2ei$13kmv$1@dont-email.me>
References : 1
User-Agent : tin/2.6.2-20221225 ("Pittyvaich") (FreeBSD/14.1-RELEASE-p5 (arm64))
peter@easthope.ca wrote:
Hi,
I have a Macintosh clone PowerWave 604|132. The user's manual is
available from the Internet Archive and other servers.
The power button on the front panel and the button on the keyboard
both cause the fan in the power supply to spin and the LED in the
front to illuminate. The display remains black.
I've tried two monitors and a second PCI video card. The display
remains black in all cases.
Neither the programmer's interrupt button nor reset button has
effect. Meaning the Apple ROM isn't working? The CPU isn't working?
Should an audible tone come from the speaker when the machine
starts?
One memory card is in each of two banks of sockets. Removing either
card yields no change.
The clock battery is probably dead but shouldn't cause this
behaviour; correct?
Adjacent to the memory are ROM and cache SSIMMs in sockets.
Reseating is worth trying but the cards are stuck hard in the sockets.
Other ideas? Poke around with an oscilloscope?
No direct experience with Mac clones, but all of my genuine
Apple machines failed from capacitor leakage causing corrosion
of the motherboards and eventual failure. How does the board(s)
look under a close inspection? Solder joints can also fail from
through-plating residue trapped in vias. Neither is likely but
both are fixable if they can be seen.
Probing with a 'scope can't hurt, but you'll want some notion
where to look for activity. Maybe near but not on a crystal?
Without some sort of schematic it'll be a long search.
There are YouTube channels devoted to fixing vintage computers,
some of those might be worth a look.
Good luck,
bob prohaska