20 Jul
2005
20 Jul
'05
12:32 a.m.
On Tue, 2005-07-19 at 20:28 +0100, Tony Duell wrote:
Conveniently, the heatsink fell off the PGA during cleaning (I wasn't
even poking at it, so the heatsink compound must have seen better days)
It wasn't uncommon to use the silicone grease type of heatsink compound
to fix small heatsinks back then. And they do then tend to fall off...
On Mon, 2005-07-18 at 17:28 -0700, Vintage Computer Festival wrote:
> On Mon, 18 Jul 2005, Jules Richardson wrote:
Having now managed to see said pictures, I wonder if the CPU is on the
daughterboard. In particular, could the PGA package be something like a
32032? The other 2 'intersting' chips on said board might be an MMU and
FPU or something. The chip's a 32332 - google suggests that's a
second generation 32032
CPU, although it's not a part number I've come across before (we've got
I've heard of it, but doubt if I have data anywhere.
some Natsemi databooks at BP; I'll have to see if
it's listed)
Next on the list is re-fixing that heatsink and
dumping the ROMs. PSU
test after that, then I need to find the battery board schematic I drew
I haev mine to hand... Incidentally, RS sold (sell?) some battery holders
that will fit in place of the tagged NiCds, straight onto that PCB (I
think that's why there are extra connecting holes for them) and you can
then fit normal AA NiCds.
ages ago for the MG-1 (they use the same board) and
figure out how to
bypass the charging circuitry...
Why do you need to do that? Why not just fit the NiCds? Or are you
talking about 'jump strarting' the machine to get it to power up in the
first place? To do that, connect a 9V battery, +ve to pin 3 of J13, -ve
to pin 2.
I happen to have the MG1 'Support Note 5', 'Jump Start Lead and Method'
in front of me.
The connector is what Maplin call a 3 way Minicon. Pin 1 is marked on the
shell, and isn't used. The other 2 pins go to the battery as I've just
described.. The procedure is to plug the canle into J13, according to the
diagram in the manual, pin 1 is closest to the fuseholder/rear panel.
When the system has booted, you unplug the lead and leave the machine
running for 15 minutes to charget the NiCds.
Of course the hard disk may well be toast, in which
case it's all for
nowt... getting MG-1 OS media is difficult enough, I expect it'd be
impossible for the 200 series machines!
No use to you at the momnet, but I do have the MG1 distribution kit.
-tony