Mega ST battery wiring?

[Muzz73]

Hello, all... I just came into a Mega ST 4 w/TOS 2.06 and am very stoked! I have a question, though...

 

I opened it up and found that the battery wiring was disconnected, there was duct tape wound around and over the battery wire connector, and there was duct tape over the connector on the wires that come from the front/left of the motherboard. I removed the duct tape from both connectors, but now I am wondering; do they plug in to each other (one is two-pin male, the other is two-pin female), or am I missing parts?

 

It's not easy for me to get photos and upload them, but I will try if it helps.

 

Any advice would be appreciated.

 

Thanks!

[+DarkLord]

That sounds right. Mine are an off brownish kinda color - they go

between the metal shielding and the upper battery compartment.

 

HTHs.

[Muzz73]

Funny thing... when I got it, the RF shield had been removed and the inside of the lid had been lined with aluminum foil and duct taped in place! As you might imagine, I have since removed said foil...

 

I can imagine that the previous owner would have done that for cooling purposes, but the foil was blocking the top vents, so out it came.

 

OK, thanks for the advice and I'll give it a whirl tonight.

[+DarkLord]

Hmm, I can't think of too many that need it right off hand, but perhaps the

previous owner pulled the metal shielding because of the upgrades he added?

(You did say it had TOS v2.06 right?)

 

Just a thought....

[Muzz73]

Yes. It has a small board with the two TOS 2.06 ROM's on it, connected to a ribbon cable that goes to another small board that is plugged into the MegaBus slot. There are two more (smaller) ribbon cables going to the first Hi and Lo ROM sockets onthe motherboard. I figured that makes sense and that is was all be part of the TOS upgrade, but there are also little wires connecting this-and-that to legs on the 68000 and a little I.C. piggybacked onto another on the far left side, toward the front. Since I've heard that there is some minor soldering involved when shoehorning a TOS 2.06 upgrade into an older ST, I didn't think anything of it, but now I am starting to wonder why that little chipis piggybacked the way it is.

I'll try to get pictures up soon.

[Zogging Hell]

Might be the blitter chip fix or maybe an FPU?

[Muzz73]

Please, if you don't mind... what is the Blitter chip fix? I've never heard of it before.

 

I wouldn't think it'd be an FPU; it's too small!

 

I'll try to get pics up tomorrow night.

 

Thanks!

Louis

[+DarkLord]

Yep, it's actually pretty common and well known. I've had a couple that had it.

Here is a page from the ADSpeed accelerator manual:

 

 

HTHs.

 

[Muzz73]

All I have been able to manage is a bad cell phone pic, but here it is:

 

https://www.facebook.com/photo.php?fbid=762767703733874&set=a.586689304675049.1073741826.100000019541825&type=3&theater

 

I hope you guys can see it. If anyone can, does this look like the blitter fix?

 

Thanks in advance!

[Muzz73]

If this is the blitter fix, how can I tell if my ST actually needs it? I read somewhere that Atari applied it to all early Megas, but not all of them needed it. Can someone verify this?

 

If it doesn't needed it, am I hurting anything by leaving it in?

 

The ST seems to work just fine the way it is, so I am very punchy when it comes to messing around with the internals. Especially being that I have been waiting many years for a Mega ST and this is the first one I have ever seen up close. I don't want to mess this up.

 

Sorry for all of the crazy questions. I have loved ST's for many years and, as I was saying, have never gotten my knuckles around one of these before. I'm pretty jazzed about it!

 

Thanks, again!

[+DarkLord]

Hmm. Really need other people with more experience to verify, but that doesn't look like

the Blitter fix that came from Atari to me...

 

IIRC, it is actually a small board with like 1 chip on it, that sits on top of the 68000 chip.

 

I'd get some other people's opinions on this...

[Muzz73]

Yeah... this is one little chip (off to the left, in the pic) piggy-backed on top of another and wired to the 68000 directly.

 

I was also wondering if it had anything to do with the battery wires being un plugged when I got it.

 

Man, now I'm REALLY curious what is it is.

[Muzz73]

I found this pic on the web:

 

https://www.facebook.com/photo.php?fbid=764420983568546&set=a.586689304675049.1073741826.100000019541825&type=3&theater

 

Is this the blitter fix? It appears to be the same size chip and the one that's stacked up in mine and also appears to be connected to the same pins on the 68000. The little board has an extra wire coming off of it, but it I might imagine that it's for power, which the piggy-backed chip seems to be getting from the one on the bottom.

 

Does this look like a blitter fix that someone might have done as an afterthought? The Mega has a dealer sticker on the underside of the case, so I know it has been serviced at an Atari Dealer (somewhere in Florida, IIRC) at least once before.