Path: utzoo!attcan!uunet!snorkelwacker!bu.edu!dartvax!eleazar.dartmouth.edu!stevel
From: stevel@eleazar.dartmouth.edu (Steve Ligett)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Mac Plus to SE/30
Message-ID: <25126@dartvax.Dartmouth.EDU>
Date: 15 Oct 90 16:07:11 GMT
References: <58220@microsoft.UUCP>
Sender: news@dartvax.Dartmouth.EDU
Organization: Dartmouth College, Hanover, NH
Lines: 51

In article <58220@microsoft.UUCP> earleh@microsoft.UUCP (Earle HORTON) writes:
>What if I rip out the logic board in my Mac Plus, and stuff in an SE/30
>logic board, an ADB keyboard, and an ADB mouse?  Anyone care to comment
>on how this will work?
>
>Earle Horton

It's been a year and a half since I did this to a KE.  The Mac has been
running fine (fast!) since.  Here's my recollection of what I did:

1.  Bought the SE/30 internal sheet metal piece from our shop.  Otherwise
    it's tough to get the logic board in and out.  And you won't be able
    to use the slot, etc.

2.  Sawed out the whole I/O area in the back of the KE case so the SE/30
    ports would stick out.

3.  Made a cable to go from the Plus power supply to the SE/30 logic
    board.  There are a couple of things that the cable has to do.  (Most
    cables don't "do" anything...)

I put a -5 volt regulator in the cable since the SE/30, sensibly,
expects the power supply to supply power.  The old Macs have a voltage
regulator on the logic board.

I put a one-shot in the cable to lengthen the vertical sync pulse.  I think
it's supposed to be about 800 microseconds.  This is from memory...

4.  For sound, I lengthened the cable from the speaker.  My power supply
    had the speaker lead on a connector; many of them have it soldered
    on.  You could put it in the cable made in #3, above.

I put a lot of grounds in the cable, just like the SE/30 one has.  I put
a ferrite on the cable, like they have.

What I thought about doing, but didn't get any farther than a drawing on,
was a PC board that gloms on the Plus power supply connector, that has
the SE/30-type Mini-fit Jr. connector on the other side.  The PC board
would do the stuff that I put in the cable, and you'd use a standard
SE/30 power supply-to-logic board cable between it and the logic board.
Is there a market for that, or what??

I don't remember any big problems.  Cutting the slot for the ports was
the hardest part.  I don't know if you can get an SE/30 logic board at
a reasonable price.  Our shop will sell parts like that.  Apple says
it's ok, as long as it's for use in a Mac, and not for resale.  Drop
me a line for more info.

Disclaimers about you being responsible go here.
-- 
steve.ligett@dartmouth.edu or ...!dartvax!steve.ligett