naujoks

The same is the case here, Delay Line is not socketed so I haven't swapped it yet. Let me grab my desoldering gun.

Yes, but back to my issue at hand...

RAM is Mitsubishi. I tested every IC, they're fine. Just for giggle I swapped them with a different set. Same result: black screen.

I have an 800XL with black screen on powering up. Voltage tested fine (tried different PSUs), all but one IC are socketed and I swapped the ICs for known working one. Clock on CPU is fine. Cartridge doesn't play. Self test doesn't run. No sound coming from anything either. Getting nice bit of chatter on data and address line on CPU. Caps look clean and not bulged. Didn't see any dodgy solder joints. No ICs getting hot. Pretty stumped on this one. Any ideas what I could try?

???

The 6810 RAM arrived today and now the drive WORKS! I'm so happy! So it was only the RAM and nothing else. Note to future fault finders: Work through the list of power on checkup in order! Last two things: which part of the spindle motor can I lubricate to make it run a bit smoother? Can the power transistors (or mosfets) be replaced with a modern, more efficient part? They run so hot!

Ha! It's true, I only have one, clearly that's not enough. I'm quite optimistic that the RAM will make a difference. It's actually the first component I was able to test faulty. Had my field service manual had all pages, I wouldn't have bought the FDCs first.

Thanks, I indeed only had the curtailed version of the manual. Glad to see that the RAM check happens before seeking track 0. I will now wait another few weeks for the replacement RAM. Meanwhile I'm still wondering if shorting pin 1 and 2 of J10 is supposed to make the r/w move, irrespective of the control logic.

Can I ask on which page of the field service manual you found this line? I just can't find it.

One of the ICs I haven't swapped yet (as I don't have any) is the 6810 RAM at U8. I tested it with my Retro Chip Tester, but it won't perform the test, reporting "Insert 6810", so there might be a possibility that this chip is faulty. Do we know if a working RAM chip is necessary to perform the inital boot up?

So the bottom line is that the only working RAM expansion for me to play Yoomp! on the 800 is the Incognito?

The new FDC arrived, the 1050 is still not working though. The drive is now spinning up and stops after 1 or 2 seconds, most of the time, but not always. The r/w head is still not moving one bit. I've seen a video where someone, in order to find out if the IR sensor is working, is shorting pin 1 & 2 of J10, which makes the r/w head move in one direction. Should this move the head irrespective of whether the rest of the drive is working or not? Again, my r/w head doesn't move at all when I'm shorting these pins. A real head scratcher, this one.

I'm not worried about the technical aspect of installing the Incognito. I might consider doing it on my 800XL. But the 800 is such a nice oldtimer. I wouldn't want to mess with it too much. They're also quite rare in Germany, let a lone expensive. On Ebay they sell for around $450!

I do own an 800XL and I'm playing Yoomp on it. I just got the 800 and I'm loving it, the picture looks amazing on my Sony PVM 14. Nothing beats using the original hardware, and I love to see the result of what happens when programmers push the hardware to do things the original designers never imagined or thought possible. It's tantalising to think that the 800, with its hardware from 1979, could play an amazing looking game from 2015, if only it has a bit more memory. The Incognito mod is great, with the many things it can do, but for my taste it's quite a big modification that changes the original machine quite a bit, plus it's not easily reversible.

Emulator? Excuse me??

Nope. I love the 800. I want to play Yoomp on it!

Ahhh that explains it then. I think I've heard about a cartridge slot based memory expansion, one that also let's your run ROM files, but I can't seem to find out anything about it. Do you know what it's called? I heard about the Incognito mod, but it's a bit too intrusive for my taste.

I'm still putting my "new" Atari 800 through the paces (absolutely loving it so far). I wanted to play one of my favourite new games, Yoomp!, but after going through the two loading screens, the game crashes to some lines and white noise. Not even the reset button works anymore. I tested the A800's memory with the SALT self test, and it's fine. Am I missing something here?

Ahh I had one of the pins wrong, got it all sorted now. OMG it's so beautiful! This computer is amazing! Atari should have found a way to make it cheaper by the time the C64 arrived...

I just got myself an Atari 800 and I'm trying to put together an SVIDEO cable to go into a Sony PVM 14 monitor. Picture and colors are fine, but the colors don't appear "smooth" but look kind of pixellated (see picture). When I connect my 800XL (using a different cable), the colours look as expected - smooth, no "pixels" I couldn't actually find a schematic of how to wire the cable correctly, but I measured through the 800XL cable, but obviously there are differences and I didn't get things quite right. Does this pixellation look familiar to anyone? I couldn't actually find any "schematics" for an Atari 800 SVIDEO cable anywhere, so if anyone has it and could send it to me, I'd be very grateful!

No, the counter works fine. It's supposed to sit between two of the bigger cogs, I just can't seem to see where.

I got an Atari 1010 in, which doesn't play tapes. On closer inspection I saw that a tiny cog wheel has become loose. It's the smallest one, probably just 1/2cm diameter. I can't figure out, where it's supposed to go. Could someone tell me? A picture would super helpful, the service manual unfortunately doesn't describe the setup of the various moving parts.

I've actually taken the FDC out, just to see what happens. The drive is still spinning non stop. It would be great if any of you guys could take the FDC out of your drive to see if it's spinning endless as well. I don't know, I just have a gut feeling it's not the FDC...

I tried shorting pin 1 and 2 of J10, as described in the Youtube video from above, but the head doesn't move. Does this point to a stepping motor failure?

The cables are definitely properly connected. I'm quite proud of my soldering, I'm sure I didn't make anything worse by replacing the sockets. The change in behaviour happened when I reseated/replaced the ICs, even before I replaced the sockets. I've ordered 5 FDCs from Aliexpress. It was a decision between those for $20 or 1 from the Netherlands for $21. I hope the Chinese ones aren't fake. It will be a couple of weeks before they arrive. I'd love to try other ways of trouble shooting in the meantime though. I have a logic probe and a scope (I'm quite new to the latter though).