17 May
2001
17 May
'01
6:25 a.m.
Once you have the epoxy portion removed, you can go to work on it with solvents
like Methyl Ethyl Ketone to soften/dissolve the EPOXY.
If it's sufficiently cold, it should pop right off the package to which it's
glued if you attack it with a sharp chisel at the boundary between the package
and the epoxy-potted appendage.
Be sure you consider very carefully and well in advance how you're going to hang
onto the thing once you're ready to do the job. This might require you build a
holding fixture so you won't damage the device. It might not be a bad idea to
consider how you're going to restore the potted portion once you've swapped the
battery. In fact, it might not be a bad idea to make a 2-part sandwich so you
can replace the battery next time as well but without the need for surgery.
Dick
----- Original Message -----
From: "John Honniball" <John.Honniball(a)uwe.ac.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, May 17, 2001 9:33 AM
Subject: Re: Slicing open the top of a 48T02 Sun Sparc chip to replace battery
is that thing hollow or filled with epoxy?
On Thu, 17 May 2001 10:55:47 -0400 "Claude.W"
<claudew(a)videotron.ca> wrote:
I am considering slicing open the part epoxyed to
the top of a 48T02 chip to
replace or hook up a new 3VDC source. I dont wanna buy a new chip....
I've done this myself...
If the thing (the top module with the batt and
osc) is not filled with epoxy
I imagine this can be done...does anybody know if that module is "hollow"
and removing the top will reveal the components inside...??? Or will I just
be cutting through solid plastic/epoxy???
It's solid epoxy. I don't think it would be practical to
completely expose the components.
Alternative method is revealing the wires coming
from top part to chip by
digging into epoxy on one side and hooking up there (from sun NVRAM faq)...
That's the method I used, just exposing part of the wiring
from battery to chip. It's not deeply buried, and the FAQ
gives the location at the end opposite to Pin 1. I didn't
even disconnect the old battery, but simply paralleled my
own AA battery holder and fitted two AA batteries.
--
John Honniball
Email: John.Honniball(a)uwe.ac.uk
University of the West of England