A 500 Franken project

[quarkx]

So, I have a good friend that has sort of been bugging me for an Amiga for a while, as he had an A500 growing up and loved to play a game called "Empire" on in. I wanted to build him a nice A2000, but like a lot of people here, it was an A500 or nothing.

SO.. Amongst the other stuff I was doing yesterday, I pulled out some A500 Pieces I had carefully stowed away. I have no A500 "ready" as most of the A500 I get in are damaged in one way or another

In my cleaning frenzy last fall, I think I threw out my "Good" A500 Shells accidentally thinking they were the broken ones.
Also, Have you seen the prices the are asking now for a base A500:wooha: Its almost tripple what it was 2 years ago here in Canada and just ridiculous as far as I am concerned.

I am filming my progress to be made into a video, but for this first post, I wanted to show you Motherboards.
First, HERE in Alberta, the only A500 motherboard revision I have ever seen is revision 5 . I am not sure if this is a local thing or if in Canada, all Commodore ever sold was Revision 5 Motherboards.
I dug up 2 Motherboards yesterday and tested them (just to the kickstart screen) and both were fine.
BUT, if you look, both are rev.5, but one is more gold then the other, the date stickers say one was 1987 and one was 1989.
I thought this was kind of interesting, also notice the difference in the Fat Agnus, same numbers, but different labeling.
The CPU's are the plain ones I have seen over and over from that time, but I usually see only Sems. not an actual Motorola.

When I have time, next is digging through all my floppy drives to try to find a good working one for him

 

[BLTCON0]

Is the green one dated 1989?
My (now dead) 1987 rev5 board is green but does include the transistor+bridge wire rework which can be seen on your 'gold' one, slightly above the CPU & ROM (even the link wire colour looks identical).
This was a documented fix for a noisy signal AFAIK, I'm surprised it doesn't exist on your 'green' one. 1989 seems a pretty late datestamp for a rev5 so maybe there existed 'corrected' rev5's after all?

 

[quarkx]

Yes, the green one has the 89/90 sticker on it.
Yes, I noticed that, but the green one has a resitor under tape between the Denise and the CIA chip just the Paula above , I wonder...

 

[BLTCON0]

Yeah that resistor actually resembles a 'fix' on some 6A motherboards. Even stranger
Maybe you have an 'almost 6A' rev5, would do good justice to the 'franken' description

 

[quarkx]

but if you look at the rev.5 Picture, it is the same as my green one. even same date sticker (89/90)

 

[BLTCON0]

I'm confused, I thought one was dated 1989 and the other 1987?
The PCBs are bound to be the same (rev5), the colour difference is due to the protective coating. It's the different level of reworking that's intriguing.

 

[quarkx]

You are correct, the "gold" date sticker says 87/88 the green one says 89/90

 

[BLTCON0]

That's a pretty early rev5 I'd say! Declaring interest! J/K
Anyhow, a photo of a late rev5 board missing the mod and generally looking just like your '89 one exists on amiga.resource.cx too, so I suppose at some point they fixed the issue. It's mentioned here.
"An authorized transistor kludge must be installed on all but the most recent A500's to clean up a signal from the Gary chip".

 

[quarkx]

I can always trade it for an A500+ mobo

 

[quarkx]

part DUEX

part DUEX

Ok, so I was up early trying to get all my shipping done and took half an hour to scrub down the shells. Yes I am still filming it all and if I spend 30 or 60 min a day, I can get this done.
here is pictures of the "pre- Clean" tomorrow, I tackle it again, to get what I missed today.
I didn't take pictures of the bottom, maybe tomorrow.
just too many things happening this week, but if I force myself to do a bit every day, I can get it done.

 

[cjcliffe]

Looking good so far; you planning to retro-bright it or just cleaning up in general?

I have those same two A500 motherboards (gold & green) that I pulled from two of my systems here (to replace with A500+ PAL motherboards). They appear to be the same year and chips as yours (except the one fat angus) and all three that I have are from Ontario, Rev5 and vary slightly in rework too.

I've nabbed two A500+ PAL from airey36's store in the past few months; they seem to show up there fairly often. Interesting that similar to the Rev5's my 500+ 8A is a green board and 8A.1 is golden :smile:. If you're upgrading I'd recommend the 8A.1 since in my experience the caps on the left side are shorter and fatter like the Rev5's making it easier to install stuff like turbo or memory boards which would be in conflict on an 8A.

Keep it up, I'm looking forward to seeing it progress

 

[quarkx]

No, Just a good cleaning.
There are 2 reasons for this:
1: I am not selling this, but giving it to a friend.
2: Here in Edmonton, I have found it imposible for a person to get a hold of Hydrogen Peroxide greater than the .003% you find at the drug store.
I have been to Chemical supply places, Hair salons, Hair salon suppliers etc.
Nobody wants to sell the stuff, and they look at you like you are a terrorist.
I have even explained to each place I went to , what its for and they refuse to sell it, if you don't have some sort of licence or paperwork or such. I spent 6 months going all over Edmonton to over 40 places and nothing. I gave up.

Yea Airy, I bought 2 A600's through him - Piece by piece, LOL, but it was a heck of alot cheaper than buying a complete one. But he had no clue that the floppy bracket was different on an A600 than an A1200. He always sent me the A1200 one and I kept shipping it back to him LOL. I thank AmigaKit for stepping up and they sent me the correct bracket.
He seems to think all the A600 parts are the same as an A1200.

I might have to break down and order from him, because nobody here wants to sell an A500+ board

 

[quarkx]

day 3

day 3

Ok, so the shells are all dry, but I still may run them through a dishwasher, If I can track one down. LOL
I did a fast clean of the Motherboard. I decided to use the latest "Green" one. No reason, it was just the first one I grabbed.
I didn't take the bottom shield of and do a meticulous job, like I do for my sale ones, just a fast, but good job. I have to wait a bit, then I can blow out all the paper towel bits left behind.
Tomorrow is the floppy drive hunt.

 

[cjcliffe]

No, Just a good cleaning.
2: Here in Edmonton, I have found it imposible for a person to get a hold of Hydrogen Peroxide greater than the .003% you find at the drug store.
I have been to Chemical supply places, Hair salons, Hair salon suppliers etc.
Nobody wants to sell the stuff, and they look at you like you are a terrorist.

That's unfortunate, I was hoping to whiten a few shells and keyboards here in Ontario myself and didn't realise it might be a hassle.

Yea Airy, I bought 2 A600's through him - Piece by piece, LOL, but it was a heck of alot cheaper than buying a complete one.
..
I might have to break down and order from him, because nobody here wants to sell an A500+ board

Lol, yeah I've patched together my share of systems here from his supply; I'll make sure to send you a PM if I happen to see another A500+ board around.

Ok, so the shells are all dry, but I still may run them through a dishwasher, If I can track one down.
...
Tomorrow is the floppy drive hunt.

Looking good so far

 

[quarkx]

Ok, just a quick update.
The floppy drive hunt is not producing any results yet, I have gone though 5 A500 drives and 4 A1000 drives, but so far all are dead.
May have to break down and buy one from Airy unless someone here has one for cheap.
I will keep you all updated.

 

[cjcliffe]

Ok, just a quick update.
The floppy drive hunt is not producing any results yet, I have gone though 5 A500 drives and 4 A1000 drives, but so far all are dead.
May have to break down and buy one from Airy unless someone here has one for cheap.
I will keep you all updated.

Wow, that seems like a lot of dead floppies for one not to at least somewhat work Did you happen to try another cable or try them on the other A500 board just to make sure it isn't the A500 floppy controller? Or perhaps give the drive heads a cleaning?

 

[quarkx]

Yep, I even have this super head cleaner thingy from AmigaKit, but on sunday I will have more time and tear a few apart. Not licked yet, just easier to get a working one. Yea, I can be a bit lazy, for stuff like this.

 

[quarkx]

So, today, spur of the moment, my buddy (who this is going to) came by to pick me up for coffee. I know he has a brand new dishwasher, so I got out the keyboard and quickly removed the 40000 Microscrews on the back and separated the membrane and electronics off and gave him the Keyboard and the shells to run through the dishwasher later today. I did make sure to pluck the LED for the Caps-Lock out first. I am going over there tomorrow, so I will pick up it all then. The silly thing, in my hast, I didn't get any Before Photos, but it was filthy.

 

[rkauer]

Remember to tell him to not do a full cycle in the dishwasher, Glen!

A cold cycle will free the board and parts from the filth and not distort the plastics heavily as a complete cycle will certainly do!

 

[quarkx]

OK, but I think it's too late, he said it was done and didn't mention any issues.
But, I may have found one floppy drive that actually works!
The bad thing is its a "Moded" drive that I think Commodore John (could be wrong) did and sold to me a few years back for an A1000. There is hot glue on the outer shield screws, so I am seeing if I can get it off and to fit, I do have a few "Back-ups" coming soon though.

---------- Post added at 22:28 ---------- Previous post was at 21:30 ----------

No, It wasn't Commodore John, it was c64dungeon (Burt) from .org
Just got to find the right stand-offs to line it up.