> I was just told that if a 128k Mac doesn't have > a flashing question mark at start up, w/out > a OS diskette in, (& it has a sadmac with error code > as mine does) it means it's "memory or logic board problems". > So, I was given a price to fix my 128k Mac from > "Sun Remarketing"... have any of you used them & > would recommend them?
I don't know how handy you are with hardware, but if you are somewhat familiar with basic troubleshooting, first measure the voltages coming out of the connectors on the back. You don't need the pinouts (although that would speed things up a bit). Just clip the negative lead of a voltmeter to the shell of the connector (any one in the back will do), then with a paper clip to help if needed, measure the voltages on the other pins. You should be able to find at least +5 and +12 from the floppy drive connector (-12, too, but that's not so important). If the +5 supply isn't within 0.25V of nominal, that's your problem. These old compacts had many, many power supply related problems. Often, it's just a case of bad connections that need to be resoldered or cleaned. If the +5 isn't right, the logic board won't function right. Stuart's suggestion about trying a 512k board is aimed at diagnosing the same thing, and is spot on. I would send the board to Sun Remarketing only as a last, last, last, desperate act. And not even then. :-) --Cheers, Tom -- Prof. Thomas H. Lee Center for Integrated Systems, CIS-205 420 Via Palou Mall Stanford University Stanford, CA 94305-4070 http://www-smirc.stanford.edu 650-725-3709 voice, -3383 fax -- Compact Macs is sponsored by <http://lowendmac.com/>. Support Low End Mac <http://lowendmac.com/lists/support.html> Compact Macs list info: <http://lowendmac.com/lists/compact.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/compact.macs%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
