I have a Mac Plus that I bought new that I am trying to get operational again. When it finally became unusable, the screen would go to a thin vertical line and sometimes it would work again if I tapped the case. This issue would happen right away upon turning the Plus on. I resoldered some of the joints (L2, C1, J1) on the analog board and it seems to be better, but there is no start-up bong when I turn on the machine. The screen appears normal with the flashing floppy icon. I haven't been able to do enough testing yet to see if the resoldering has fixed the issue after it has been warmed up for a while. What is the cause of no start-up bong?
The flaky joints you particularly need to check are the ones associated with the 4-pin connector that goes between the analog board and the "yoke" around the crt's neck. Resolder (with fresh solder) the connections on the analog board. Then, undo the connector and inspect the pins in both halves. In some cases these get damaged from the heat produced by the flaky contact. Repair or replace as necessary. As to the "no bong" problem, double-check the speaker, the capacitor in series with it (you'll have to do a little tracing), and the connections associated with them. And as to your other question about the "micro screen" logic board, doublecheck your ram. Make sure that the ram is good, installed properly, and that the ram size resistor is configured correctly for whatever ram capacity you've got. For other details, there are some troubleshooting hints, along with a schematic of the Plus analog board here: http://home.earthlink.net/~gamba2/images/plus_analog.PDF --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:compact.macs@mail.maclaunch.com> 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/> --------------------------------------------------------------- iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com ---------------------------------------------------------------
