florman@randvax.UUCP (Bruce Florman) (06/22/88)
Over the last couple of days the screen my faithful old Mac Plus
has started to jump and flicker rather badly. I recall from other
people's horror stories that the Mac has a failure mode where the
screen goes black with a narrow white stripe running up the middle
:-(skunk mode). Can anyone tell me what part is going bad, and
whether or not there is any advantage in getting it fixed before it
goes out altogether?
I know that SOP at most authorized Apple service centers is to
simply swap out the major components until the problem goes away,
and then charge poor sucker, er, valued customer, the full price of
the board. Can anyone recommend a shop in Southern California which
will fix a problem at a lower level (ie. less expensively) than this?
-Thanks for any help,
Bruce Flormanlandman%hanami@Sun.COM (Howard A. Landman) (06/28/88)
In article <1531@randvax.UUCP> florman@randvax.UUCP (Bruce Florman) writes: > Over the last couple of days the screen my faithful old Mac Plus >has started to jump and flicker rather badly. I recall from other >people's horror stories that the Mac has a failure mode where the >screen goes black with a narrow white stripe running up the middle >:-(skunk mode). Can anyone tell me what part is going bad, and >whether or not there is any advantage in getting it fixed before it >goes out altogether? I had similar symptoms last week, although the brightness was also way down, so you could only see the stripe with it turned up all they way. It turned out to be that capacitor C1 on the analog board was blown. This is a 3.9uF, +-20%, 25V, (bipolar?) electrolytic capacitor. I had trouble finding a replacement, so I bought four 1.0uF 250V metallized film capacitors from Radio Shack and soldered them in parallel to make 4.0uF. Cost of parts was about $3.81 including tax. If C1 *is* blown, it may not be obvious from casual inspection. All I saw was that the board was a little brown there (indicating overheating?), and the top of the can was *slightly* bulging. After removing C1, I could see cracks in its base around the leads. I have been told that you can get similar symptoms from cracked solder joints on the analog board or the CRT yoke, but mine looked OK. Howard A. Landman landman@hanami.sun.com UUCP: sun!hanami!landman