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Macintosh SE - C23 Resistor


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Hello all. I'm new to this forum so apologies if I'm out of step in any manner.

 

Today, I received a Macintosh SE in the mail. Simple as that, I ordered it off eBay on the 25th. It had a 4MB RAM upgrade, although a sticky (but manageable!) hard drive. This was my first toaster-style Macintosh.

 

A few hours into using it, I turn the power switch on, and the video on the monitor comes up strange (distorted and out of focus). During a hasty Googling session, I can smell very clearly that something has gone terribly, terribly wrong. The distinctive smell of vintage electronics burning. Turns out that it was a literal toaster Macintosh.

 

In the final seconds before I turned it on, it very clearly "dropped out". The fan and the HDD shut themselves down (or something).

 

I rapidly unplugged it and waited for the smell to clear. After a few minutes, I opened it to inspect. My instincts told me to check the flyback and the analog boards. Nothing on the flyback looked wrong, no components had exploded, everything looked in-order. After a sniff-down, I could tell that the smell that sends my blood pressure flying (higher than it already is!) was coming from the rear half of the analog board and potentially the power supply.

 

After a closer inspection, the C23 capacitor looked somewhat suspect, but I'm not sure that would cause such a drastic issue. I attached a photo of it.

 

What might be the issue here?

 

Thanks

post-7688-0-63176800-1483066416_thumb.jpg

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"Somewhat suspect"...

That's not a capacitor, it's a resistor. And it is /FUBAR/.

My copy of the Mac SE Analog Board schematic says that C23 is a ceramic disc capacitor, rated .1uF 50V (the code on the capacitor would be 104F ...) between the 5V out and the GND.

Is there another component name nearby, on the other side? Preferably beginning with an R or possibly a CR? 

Also, be prepared for the possibility that it might have cooked some other things in its dramatic failure.

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That clear stuff is glue, nothing to worry about.  

 

My Dead Mac Scrolls book references possibly rectifier CR2, CR3, transistor Q2, flyback transformer, resistor R22, R19, and capacitor C15.  If you want more information on those pages of the book, PM me

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