Where great old Macs live again!

I acquired a Mac 128k/512k (it came with both logic boards) and a GCC HyperDrive 20 Mac 512k over the last few years ago. Since then, I've spent a lot of time examining the innards of these two classic beauties. Being an electronics hobbyist with an EE degree, I certainly enjoy tinkering. One thing I discovered is that electronic components, especially old electrolytic capacitors, are often in need of replacement to get the machine back in original working condition. I visited a variety of sources on the internet which offer parts listings of the original analog (power supply) board of classic Macs, and I also purchased an old copy of Larry Pina's excellent Macintosh Repair and Upgrade Secrets book (ISBN 0-672-48452-8). (And for those of you who think Steve Jobs looks "frail" now, just have a look at the black and white photo of Pina on the back of his book!)

Using the information resources at my disposal, I began to compare the components listed with the actual components on each of my analog boards. I eventually purchased replacement analog boards off EBAY and subsequently compared those components as well. (I have uploaded 3 sets of analog board photos on Flickr for your viewing pleasure.) I came across some errors and new information that was not listed anywhere else, so I decided to compile my own components listing, focusing on the most likely parts in need of replacement. You can view my Mac analog board components list here. (Please don't overlook the fact that there are two sheets available for viewing, selectable at the bottom of this spreadsheet.)

I hope this serves to assist those of you interested in tinkering or otherwise repairing (or even upgrading) your existing Mac analog boards.

Views: 1795

Comment by Stephen on May 16, 2014 at 8:34pm
Hello James,
Have a question regarding c1, the 3.9 uf cap on your cap list.

Comment by James Wages on May 17, 2014 at 3:14am

Hi Steve,

Regarding C1, did you click the "Mac analog board components list" hyperlink above?  That opens a Google Docs spreadsheet and gives a lot of details, not only about C1, but about many other components too.


Comment by Stephen on May 17, 2014 at 11:22am
Yes. It's a great resource. Thanks for doing it.
When I check digikey for c1, it shows a non electrolytic type capacitor. I know this one is hard to find and I'm in need of some. I have four compact macs that are going through a cap job on their analog boards. I have some coming from another member on 68klma forum, but will be needing more for a couple of pluses on their way.
Believe I'm entering the right part number and even a search on several parts sites don't show the right cap.
Also believe you are on 68klma since that's where I first saw this list.
Any clarification on the cap would be great. Thanks
Comment by James Wages on May 17, 2014 at 6:07pm

Correct.  The suggested replacement for C1 is NOT an "electrolytic" capacitor but rather a Polypropylene (PP), Metallized film capacitor that is Not Polarized.

Yes, I've been on the 68kMLA for many years.  I am known as "JDW" there.  What is your name there?

Comment by Stephen on May 17, 2014 at 8:03pm
Thanks for the info. Connected the caps to my SE and SE30 and both fired up!

I've seen your user name on the 68klma. I wasn't very clever and used my name, Stephen Morimoto.
Have had several questions and help on the other forum. Everyone has been very helpful.
Continuing on my quest to get my macs up and running again.
Comment by James Wages on May 18, 2014 at 4:03am

Using your name is clever.  JDW is my name, or at least, my "initials."  :-)

By the way, I noticed your name is Morimoto.  Were you born in Japan?

I'm originally from central California, but I've lived the last 20 years in Japan (Aichi Prefecture, near Nagoya).


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