600XL from eBay

[Dr Memory]

Well.  This doesn't seem like a good thing.

It did say "untested"!  Interestingly, it boots, and I get a plausible response from ?FRE(0) (13326), but as you can see, it is not a happy camper.

 

Keyboard issues too.  Not sure what else yet.  Oh well, opportunity to learn things!

[BillC]

1 hour ago, Dr Memory said:

Well.  This doesn't seem like a good thing.

It did say "untested"!  Interestingly, it boots, and I get a plausible response from ?FRE(0) (13326), but as you can see, it is not a happy camper.

 

Keyboard issues too.  Not sure what else yet.  Oh well, opportunity to learn things!

Hopefully the memory issue is just the 2 RAM chips since they are replaced when doing a 64KB upgrade anyways. 

 

If you want to eliminate other potential faults causing the bad RAM test result you could install an SRAM upgrade board instead of 4464 DRAM/jumpers.

 

Lotharek sells a 64KB SRAM board replaces the base RAM and connects to the CPU socket, plus 1 or 2 jumpers wires.

tf_hh sells a 576KB SRAM board that replaces the base RAM and also a 512KB RAM expansion, it connects to the ANTIC socket plus some jumper wires. I would not recommend this upgrade for a VBXE equipped system.

 

These products are also available from the following US resellers:

https://thebrewingacademy.com/collections/atari-800-xl-xe-xel-xld/products/64k-sram-module-for-xl-xe-computers

https://www.vintagecomputercenter.com/product/576k-sram-memory-expansion-for-the-atari-600xl

[Mazzspeed]

11 minutes ago, BillC said:

Lotharek sells a 64KB SRAM board replaces the base RAM and connects to the CPU socket, plus 1 or 2 jumpers wires.

It's just one jumper wire, very easy to install and a quality product using a precision socket. My only complaint would be that it just touches the underside of the keyboard in the 600XL. I installed this upgrade yesterday.

 

I find the board layout on the XL series odd, why didn't Atari put all the heat producing main chips at the top of the board where there's more space and ventilation?

Edited April 8, 2021 by Mazzspeed

[BillC]

Just now, Mazzspeed said:

It's just one jumper wire, very easy to install and a quality product using a precision socket. My only complaint would be that it just touches the underside of the keyboard in the 600XL. I installed this upgrade yesterday.

The CPU socket could be replaced with a lower profile socket, this would improve clearance issues.

Just now, Mazzspeed said:

 

 find the board layout on the XL series odd, why didn't Atari put all the heat producing main chips at the top of the board where there's more space and ventilation?

The RF shield may have been part of the thermal design, it should absorb localized heat from the air and since the metal is a good thermal conductor spread it out, acting as an indirect heatsink.

[Mazzspeed]

14 minutes ago, BillC said:

The CPU socket could be replaced with a lower profile socket, this would improve clearance issues.

I have a precision socket here that I was planning on fitting, but the factory socket was in good nick so I didn't bother. Looking at both I couldn't really see any notable clearance benefits to be gained by swapping sockets - Unless there's sockets with a lower profile than my own.

 

You could remove the socket altogether and solder the upgrade directly to the board, you'd want to make sure it works first however...

 

Edited April 8, 2021 by Mazzspeed

[BillC]

3 minutes ago, Mazzspeed said:

I have a precision socket here that I was planning on fitting, but the factory socket was in good nick so I didn't bother. Looking at both I couldn't really see any notable clearance benefits to be gained by swapping sockets - Unless there's sockets with a lower profile than my own.

Millmax makes some low-profile machine pins sockets that are about 1/2 the typical height, the Millmax 115-47-640-41-003000 is a 40 pin socket of this type.

[Mazzspeed]

4 minutes ago, BillC said:

Millmax makes some low-profile machine pins sockets that are about 1/2 the typical height, the Millmax 115-47-640-41-003000 is a 40 pin socket of this type.

Ah, OK. I might look into it as the upgrade 'just' separates the case slightly in the middle. Having said that, its a quality upgrade that is easy to install.

[BillC]

2 minutes ago, Mazzspeed said:

Ah, OK. I might look into it as the upgrade 'just' separates the case slightly in the middle. Having said that, its a quality upgrade that is easy to install.

These sockets are only 0.095", most machine pin sockets are 0.165", I believe the original sockets used by Atari are about 0.2".

 

Mouser.com has them for $2.24ea. and they have 34 in stock, I couldn't find any other online retailers that have them in stock. 

[Mazzspeed]

22 minutes ago, BillC said:

These sockets are only 0.095", most machine pin sockets are 0.165", I believe the original sockets used by Atari are about 0.2".

 

Mouser.com has them for $2.24ea. and they have 34 in stock, I couldn't find any other online retailers that have them in stock. 

That's valuable information! Thanks my Friend.

 

I think I'll grab one as it's just make the install the slightest bit neater. I recommend the 64k upgrade however.

[Dr Memory]

Wow!  Thanks for the memory upgrade info, guys!  I will almost certainly do that - I never intended to live with 16K. 

 

I did a little more testing on this thing.  Three keys are dead - left shift, BRK, HELP.  Odd assortment.

 

The memory passes the internal test, and SALT, just not Sys-Check.  I certainly trust Sys-Check more!  I was shocked to see all that red.  I have some known good DRAM chips and a memory tester so should be able to figure out what's going wrong.

 

However, I hit a snag.  It took me quite some time to disassemble the thing, and I found to my surprise that it is not socketed!  I thought all 600XLs were socketed?  So I can't just pop the DRAM and test it, there will be some work involved.  Huh.

 

So that's going to slow me down a bit.  On the bright side, it already has the video components filled in, which also seems unusual - I expected to have to get a kit or a bunch of discrete components and do that myself.   Maybe because it's PAL?  Are PAL 600XLs known to have their video stuff already populated and no sockets?

 

The picture quality isn't bad, but is composite only, no Chroma nor Luminance.

 

I'm letting it rest for a little bit here, had to use WD-40 to get a couple of the screws loosened.  It seems likely this thing was never opened before.  But if that's the case, then I'm very confused about the video situation.  I'm also very confused, almost shocked at the lack of sockets.  Guess I need to do some more research here.  And some desoldering, of course.

 

[mimo]

Are you using the syscheck by tf_hh? Pretty sure that requires 64k base ram to work 

Edited April 8, 2021 by mimo

[marauder666]

My PAL 600XL had the all the video components fitted, a bit annoying when I came to fit the UAV.  I took the entire stock circuitry out.

Fully socketed too.

[Dr Memory]

1 hour ago, mimo said:

Are you using the syscheck by tf_hh? Pretty sure that requires 64k base ram to work 

Hmmm.  I am, and I think you're correct.  I actually checked first, and saw where it said "Sys-Check also works fine with an Atari 600 XL", but somehow managed to miss the rest of the sentence.  Oopsie.  So that's probably a bogus bad memory report I'm getting.

 

I'm still gonna have to socket the DRAM as a minimum, and probably a lot more than that if I'm gonna put in a video upgrade as well.

Edited April 8, 2021 by Dr Memory
minor typo

[Dr Memory]

Ok, I ordered some 4464s from eBay.  It looks like most of the upgrades require those.  Bummer as I already had 4164s in stock, but so it goes.

 

I'm pondering the precision socket thing.  Several people here seem to swear by them, but I haven't actually had any trouble with the good old cheap sockets, ever.  The only real advantage I can see for switching is the lower profile but perhaps I'm missing something.  To be fair, the low profile argument is a pretty good argument for something as crowded as a 600XL, but in general this reminds me of the "you must immediately replace all of your capacitors" thing.

 

Oh, a little more on the "no socket" thing.  I saw in a couple of threads here that some very late PAL 600XLs have partial sockets or no sockets.  I guess I just got lucky.    There is no date code on the bottom of my machine, but it says this, in various spots:

 

Serial No. 72RHA

B-035

8409654

Made in Taiwan

 

I don't know how to interpret the serial number or the B-number or anything, perhaps there is a clue there for those more knowledgeable about the history of these things?

 

And just for the humor of it, I happened to notice this on eBay today:  https://www.ebay.com/itm/ATARI-600XL-COMPUTER-Retro-games-vintage-serial-no-72RHA/284234009218?hash=item422daaca82:g:QZwAAOSwrLZgVhug

 

That is the same machine I just bought, from the same vendor.  WTF?  When I say the same machine, I mean that even the pictures match, though it's listed for more than mine was.  I'm thinking the vendor has gotten his wires crossed somehow.  Maybe he had two?  Very odd to see the same serial number for sale, that I'm holding in my hand...

[mimo]

Wow, I've never seen a 600xl without sockets before. I guess you were unlucky.

All pal 600s have the full video circuitry though.

As for video upgrade, I can highly recommend sophia2, it's stunning.

Edited April 8, 2021 by mimo

[Mazzspeed]

35 minutes ago, mimo said:

All pal 600s have the full video circuitry though.

They have the ability to output chroma/luma from the monitor port, but it's not connected from factory. Use FJC's video guide on modding the output and the resulting IQ is stunning.

 

Here's a shot of my 600XL with the mod in place (a word of warning, in that shot I had the polarity of the cap reversed, I quickly realized my mistake before firing the machine up, but forgot to take a photo):

 

[Dr Memory]

Thanks again Mazz, that looks well worth doing.  I'll probably wait until I get the memory going properly though, in case things go bad.

 

I assumed that Sys-Check would allow me to use the external memory function even on a sad 16K 600XL, but it appears that tf_hh really means what he says about it not being happy if your 600XL lacks 64K of main memory.  Even with it set to use 64K from the board instead of system memory + the 512K expansion, well, it actually doesn't and just goes to system self-test.  Fair enough, the manual actually said it wouldn't be happy in this circumstance.

 

Oh well.  The reason I dug into this is I was hoping to use my SIDE3 cart on it, because most of my validation and test programs are on there.  No joy, so I copied them to Ultimate, but it's a bit fussier, AND it turns out most of my stuff needs more RAM than that.  Even, to my surprise, some things I wrote.  16K isn't very much RAM!

 

Oh well, maybe I'll spend some time socketing things while I wait for my 4464s.  I've got a dead 1050 to fix too, so not like I'm bored.

[archeocomp]

I was anticipating that your 600XL is Made in Taiwan. Only those Made in Hong Kong are socketed.

[manterola]

I also got a PAL 600XL not socketed made in Taiwan. Since it's PAL it came with the DIN for monitor output and with the whole video output circuity populated.

I put a couple of 4464 and with 3 wires I performed the 64KB memory upgrade. It is obously more difficult than with the socketed version.

The output IQ is great after you do what is needed to get the lumma+chroma in the DIN monitor connector.

Here a couple of topics that might be interesting to you

 

 

Edited April 9, 2021 by manterola

[Dr Memory]

1 hour ago, manterola said:

I also got a PAL 600XL not socketed made in Taiwan. Since it's PAL it came with the DIN for monitor output and with the whole video output circuity populated.

That sounds just like mine.  PAL, Video circuitry populated, DIN connector present and working but no Y/C yet, and no freakin' sockets.  That last one is the only one that bugs me - didn't previously even know it was a possibility!  Well, now I do.

 

Thanks for the links. 

[Mazzspeed]

7 hours ago, Dr Memory said:

Thanks again Mazz, that looks well worth doing.  I'll probably wait until I get the memory going properly though, in case things go bad.

 

I assumed that Sys-Check would allow me to use the external memory function even on a sad 16K 600XL, but it appears that tf_hh really means what he says about it not being happy if your 600XL lacks 64K of main memory.  Even with it set to use 64K from the board instead of system memory + the 512K expansion, well, it actually doesn't and just goes to system self-test.  Fair enough, the manual actually said it wouldn't be happy in this circumstance.

 

Oh well.  The reason I dug into this is I was hoping to use my SIDE3 cart on it, because most of my validation and test programs are on there.  No joy, so I copied them to Ultimate, but it's a bit fussier, AND it turns out most of my stuff needs more RAM than that.  Even, to my surprise, some things I wrote.  16K isn't very much RAM!

 

Oh well, maybe I'll spend some time socketing things while I wait for my 4464s.  I've got a dead 1050 to fix too, so not like I'm bored.

Yep, you can't do a lot with 16 whole kilobytes (around 13 kilobytes usable) - SIDE3 won't even work with only 16k.

 

The upgrade to 64k is virtually a necessity for a truly usable system unless you just want to plug in carts and play games like some console.

[Dr Memory]

Update on my little 600XL project!

 

It was taking a while for the DRAM to get here, so I decided to re-chip the board.  Yes, the whole board.  All 23 chips.  This is by far the most ambitious such project I've ever taken on.  In the end, it worked out, but there were... issues.

 

Here we have the same system (as shown on post 10 above) with all the chips desoldered.  Ugh.  Full disclosure - I did this as well as I knew how, and still broke two chips and a capacitor.  It turns out that my desoldering gun has multiple levels of cleaning that it may need, and I didn't understand that it needed the full teardown and filter replacement until I had pulled up a couple of traces.  Oops.

 

Anyway, here it is, after the de-soldering (de-chipping?):

 

 

I certainly learned a lot by doing this.  Next time I have to remove a socket I think it'll go a lot more smoothly.  However, I hope to never have to de-chip a whole board like this again!

 

I snapped a capacitor, the one to the left of GTIA, while I was trying to pry GTIA out.  It wasn't quite as strong as expected.  I wasn't able to find an exact replacement - I don't know where to get those weird axial aquamarine caps Atari used on these - so I replaced it with a more common disc cap.  I checked the voltage of the original and this should be fine.

 

The bigger problem is, I killed the 74LS14 and the 74LS138.  Oops?  Both of these had to do with the desoldering gun not having the effect I was expecting, and me not understanding that until too late.  Lesson learned - if it seems like you're getting less suction, you are, and never ever force things when pulling out a chip!

 

I didn't have either in stock and had to order and wait, as all of the Radio Shacks in my area are gone, as well as the Frys.    Oddly, they still both got here before the DRAM.  /shrug

 

So here is the end result of the socket installation:

 

 

You can see the replacement cap on the top of the left picture.  Those yellow jumper wires on the bottom of the board are the other thing I had to fix - apparently I delaminated a couple of the holes on the 4050 while trying to desolder the chip.  Again, I tried to force things when desoldering didn't feel right.

 

It was a little challenging to fix, as not all of the problems were visible, even with a loupe - I had to trace things out with a multimeter to figure out why I was missing colors and luminance values and such.  Things like the SuperSALT cart are great for normal problems but not so helpful if you have a lower-level problem like a chip with impaired connectivity.

 

Anyway, I didn't give it more memory or better video yet, I just thought someone might be interested in seeing my socketing adventure.

 

I think if I ever get another non-socketed 600XL I'm just gonna turn around and re-sell it.  What a pain!

 

Final toll - 23 sockets (various sizes), 1 capacitor, 2 logic chips, a few small lengths of wire, and a truly impressive headache.

 

Edited April 16, 2021 by Dr Memory
tried to fix weird artifacts, not sure if it worked

[Mazzspeed]

The trick regarding keeping desoldering guns clean is to make sure you poke the steel 'pipe cleaner' through the nozzle and into the solder chamber a few times before letting it cool down.

 

This is the one I have (I've noticed many people have the same unit under a different brand) and it's never missed a beat since I learned this little tip. Good job however!

 

 

 

[Dr Memory]

Thanks!

 

I've got the Hakko.  Basically, I had to use both the pipe cleaner and the thicker cleaning tool that you use after you remove the tip.  I didn't realize how much power the thing had lost until I got all that sorted out.  When I first tried to stick the tool in there it wouldn't even go in it was so clogged and degraded.  I've been emptying the solder repository every session or two and thought that was all that was needed.  That'll teach me to assume!  Well, briefly at least.

 

Even with the little problems with the 600XL project, I don't regret the desoldering gun purchase - it was life-changing!  I never would have even attempted a project like this in the past.

 

Oh, I just finished upgrading the 600XL to 64K.  I used one of the methods linked, the one with 3 wires.  It really doesn't look too nice - apparently I still need to learn how to cleanly solder wires to bent-up pins and pins on chips in sockets - but it works.

 

Little adventure - at first it didn't work, so naturally I was cursing myself and checking and rechecking my work, as it doesn't look all that tidy.  I finally thought to try different chips.  Sure enough, 2 of the 6 chips I bought from eBay are bad!  On the bright side, now I can use Sys-Check to figure such things out.  So yay, it works, and it's socketed!  Just like a real boy er 600Xl. 

[Mazzspeed]

35 minutes ago, Dr Memory said:

Thanks!

 

I've got the Hakko.  Basically, I had to use both the pipe cleaner and the thicker cleaning tool that you use after you remove the tip.  I didn't realize how much power the thing had lost until I got all that sorted out.  When I first tried to stick the tool in there it wouldn't even go in it was so clogged and degraded.  I've been emptying the solder repository every session or two and thought that was all that was needed.  That'll teach me to assume!  Well, briefly at least.

 

Even with the little problems with the 600XL project, I don't regret the desoldering gun purchase - it was life-changing!  I never would have even attempted a project like this in the past.

 

Oh, I just finished upgrading the 600XL to 64K.  I used one of the methods linked, the one with 3 wires.  It really doesn't look too nice - apparently I still need to learn how to cleanly solder wires to bent-up pins and pins on chips in sockets - but it works.

 

Little adventure - at first it didn't work, so naturally I was cursing myself and checking and rechecking my work, as it doesn't look all that tidy.  I finally thought to try different chips.  Sure enough, 2 of the 6 chips I bought from eBay are bad!  On the bright side, now I can use Sys-Check to figure such things out.  So yay, it works, and it's socketed!  Just like a real boy er 600Xl. 

You've done well. I'm a lazy bugger, I would have just added precision sockets to the chips I was removing for upgrades!