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Super Monaco GP Airdrive

Hi,
it would be good if you had soldered sockets, so you could now swap the RAM with each other. You could possibly do that and check if no vias were destroyed or interrupted.
Without a logic tester it will be difficult to find the error.

Before you continue, put the 2 EPROMs IC20 and IC29 for the SUB program of the second 68000 CPU back into the sockets and repeat the diagnostic test. Then take another picture of the test screen.
 
OK, what a looooong day that was but at least progress.

I pulled the LS chips as it was easy, still had a short. Pulled IC 41 (the larger custom), STILL had a short, pulled IC 37 (the tiny custom) short gone! The issue? Solder paste on the underside ffs! Needless to say there was swearing!

So far I've reinstalled IC 41 pin by pin, still no shorts :)

Tomorrow I'll try IC 37 pin by pin (that'll be fun!). If I can get that on with no shorts I'll socket the RAM, fix the broken tracks, socket the LS chips and test....

Will it work? Who knows, somehow I doubt it but at least now I know 100% that IC 41 is GOOD so at least I'll have something to work with....assuming I get the RAM working with no errors.

I have a logic probe on order so that may come in handy :)

These boards are a PIG to work on, reminds me of the Amiga which were terrible too. Atari ST's were easy.....ironically I was an Amiga man though!
 
Ok, quick update. I've taken out the LS chips in this area too, I've ordered all of the chips (RAM & LS) and some sockets so as soon as that lot arrives I'll get them installed & repair the broken traces on the RAM. I've re-soldered IC37 & IC41 pin by pin under magnification, took ages but I now know 100% there are no shorts or lifted legs!!

If it still fails after all of that I'm hoping a logic probe (with the help of others knowledge!) may point to what the issue is.

If I have to trace every pin of IC37 & IC41 I will! I've come too far now to give up!!
 
sega_man said:
Ok, quick update. I've taken out the LS chips in this area too, I've ordered all of the chips (RAM & LS) and some sockets so as soon as that lot arrives I'll get them installed & repair the broken traces on the RAM. I've re-soldered IC37 & IC41 pin by pin under magnification, took ages but I now know 100% there are no shorts or lifted legs!!

If it still fails after all of that I'm hoping a logic probe (with the help of others knowledge!) may point to what the issue is.

If I have to trace every pin of IC37 & IC41 I will! I've come too far now to give up!!
Click to expand...
love your updates... I know it's going to work in the end.
would be BUSSIN' if you could add pictures along the way so we can see the sweat and tears!
 
I REALLY hope so, what with buying tools and parts I've spent more than I should have, but it's great game and one I wish to play badly with a cool beer!!

Here's the customs back in : -

20221103_174027.jpg


& the LS/RAM unpopulated at the moment, will all be socketed, the underside is where there will be a few jumper wires to fit!!

20221103_174031.jpg
 
I feel your pain ...
socketed these (wec Leman) and ... it is worst ||
 

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Parts arrived from Retroclinic (top service as ever). Got as far as the RAM sockets. Will jumper broken tracks over the weekend. Also took out an unused ROM socket to see how easy they come out. Why?! All of mine look dull. Probably OK but will see.
 
Well today did not go well. I started fixing the broken tracks, got it all wired up and I have a short again! Literally removed everything I had done...Still got a short! It can't be on the two customs as I soldered each one pin by pin and checked for shorts as I went!
 
Well..it WAS on the customs....the small one again! Really don't know how as I checked each pin as I went. Waiting on more sockets now! At least the LS chips are socketed and in now...

20221106_155734.jpg
 
Only just seen this, I guess shipping could be a killer but where is this? Thanks!
 
Seems to be a few, can you message me a link to the group/this person? Thanks!

Edit, found it!
 
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