Commodore Amiga 600 Green Screen Repair

[@retro_noix]

Amiga is the new Atari! 😉👍

[@user-Atamigaputer]

Lol Flash jazz swear at the cat. Seriously Jonathan, that was top notch troubleshooting and obviously a great deal of patience and persistence, well done

[@flashjazzcat]

Thank you so much - that's really appreciated. Feel free to share the video among the Amiga community (I'm afraid deviations from Atari hardware on this channel don't seem to get much traction from the KZbin algorithm).

[@user-nd8zh3ir7v]

Wow you make the surface mount stuff look easy, great job and video!

[@flashjazzcat]

Thank you. I actually find SMD a lot less time-consuming, although I do need strong magnification these days. :)

[@Mind-your-own-beeswax]

You did a good job of it Jon. Since you repaired it I’ve upgraded the ram to 8 meg and the floppy drive seems to work just fine thankfully. Can’t find any key caps just yet but it may need a new keyboard.

[@flashjazzcat]

That's good news regarding the floppy drive. I suppose there's a limit to how many hidden issues a single system can actually have. :) I assume the 8MB is 'fast' RAM on a trap-door board.

[@Mind-your-own-beeswax]

@@flashjazzcatit is fast ram but not in the trapdoor. It piggybacks onto one of the chips. Also upgraded the rom from 2.0 to 3.2.

[@firsteerr]

hold on a mega bite of RAM ??? why thats crazy talk !!! seriously i have dabbled around a few speccies and watching others doing the work helps me understand the problems and fixes like an engineering job its all about learning from others and not just book learning

[@adameberbach]

Well spotted and smart fix. These are great little machines except that they are hard to equip for WHDLoad (accelerator + memory); the PLCC CPU makes it difficult to fit anything to the CPU direct and there is no CPU bus like the A1200 offers. The keyboard is difficult - I did a replacement keyboard project a couple of years ago (A600KB on github) and am working on A600KB2 currently with low-profile switches. An amibay user, steveed, has had sets of MX-stem keycaps in the correct A600 sizes made at Signature Plastics, I have a set here and it is perfect right down to the 8U space bar.

[@flashjazzcat]

Thanks! Definitetly a nice little machine, but I didn't know enough about the Amiga platform to consider the shortcomings you mention. The owner was apparently intending to send a 1200 in for recapping at some later date; hopefully he does, since I was very much looking forward to getting my hands on it (I think I used a 1200 once in my life for five minutes about thirty years ago).

[@Mind-your-own-beeswax]

I’ve got OS3.2 on the 600 now with WHDLoad but it’s not without issues. I will get around to it at some point though and sort it out properly.

[@MoparStephen]

Nice diagnosis on this one.

[@flashjazzcat]

Thanks!

[@c1ph3rpunk]

Wait, there are computers other than Atari? Say it ain’t so. 😂 That being said, I’d love an Amiga with a Video Toaster in it, the computer that moved me into MIS (what it was called then, now we say IT). What are you using for the overhead camera?

[@flashjazzcat]

I'm using a pair of Logitech Brio 4K USB C webcams. Quite nice but possibly a bit long in the tooth now. I recently bought an arm-mounted magnifier with a ring-light and I occasionally shoot small stuff straight through the magnifier.

[@perinoid]

Recapping of an A600 that's ina "factory state" is an obvious move. So obvious, one can decide for it blindfolded, without looking at the motherboard. An A600 needs a pair of RAM chips to boot - with just one it has a half of its bus working. Watching the rest now. 😊

[@flashjazzcat]

Yes: I wasn't sure how the memory bus worked at the time and had read a forum post where someone claimed to have run such a machine with one good DRAM when troubleshooting, but I wasn't to know at the time if this was fiction. I'm not into pre-emtpive recapping unless there's good reason for it, but the owner was happy to pay for it and it clearly needed doing in this instance.

[@perinoid]

​@@flashjazzcat Just like an A1200 or CD32 -,, if not recapped yet, an A600 MUST be recapped or it will stop working. The faulty delay line was an effect here.

[@flashjazzcat]

@perinoid Right you are. Caps weren't the issue here, but I guess it's worth doing if it's a known problem with these machines.

[@flashjazzcat]

Turns out there was an issue with U17 (rear DRAM), and the system does in fact boot with only U16 present. See here: forum.amiga.org/index.php?topic=71796.0

[@Chriva]

The audio caps are hopeless to remove. Pretty much forced to remove the audio jacks and keyboard connector to reach them

[@perinoid]

This is how you're doing it. Exactly.

[@ChuckyGang]

Thin nozzle remove the top part of the keyboard connector. kaptontape. problem solved. no removal needed of keyboard connector OR audiojacks

[@waltciii3]

I think I will stick with fiddling with 8 bit machines. Anything with SMD components is too much for me and my eyes.

[@flashjazzcat]

I actually prefer SMD to thru-hole since the workflow is about five times quicker, but unfortunately most of the stuff I'm sent is thru-hole. :)

[@PG-gs5vb]

After all, Amiga is the actual Atari 800 successor.

[@gryzman]

the failure of amiga 600, that lead to Amiga's demise

[@tiannaumann]

I think at that price point, it should have just been an AGA chipset but the entry-level model (sold at a small loss). The A1200 could have been an A1200HD by default and a price hike to reflect , and the A4000 as-is. OCS/ECS while still capable, but unfortunately was 6-8 years old by the time the A600 released.