Fried 130XE - yet another one...

[Faicuai]

Well, for those who routinely work with this machine:

 

I've got one unit, in my vault, which happens to be a "rescue".

 

After finishing a full exterior & keyboard restoration, as well as inside cleaning (without any further tampering or intrusion past shields, etc.) I decided to turn it on, and instantly found a GREEN-SCREEN with absolutely no other activity.

 

This is a short summary of my troubleshooting efforts, so far (and no success):

 

1. Inserted Star-Raiders in cart slot (which boots immediately), and nothing (just green screen).

2. Machine has 16x 4164 chips. Placed 8x new on TOP of the existing ones (one-by-one, and then all eight, carefully aligned), column by column. No luck.

3. For the heck of trying, placed NEW rom (61598B) on op of existing one (just in case)... nothing.

4. Left on for 20mins, checked temperature: ram-bank slightly warm (both-columns), CPU hot, GTIA warmer, and the rest seems slightly warm (nothing weird).

5. CPU and GTIA seem socketed. Replaced both with new units, and exactly the same F-green screen.

6. Checked some basic signals (around MMU) like Halt, reset, R/W, etc, and could not see anything strange on the scope (but nothing formal to compare against, though).

7. Could not test (piggy-back) the 24947 because don't have a spare one... nor I am going to open-up my 800XL just for this...

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

Any tips or additional troubleshooting suggestions would highly appreciated.

[Almost Rice]

Refer to this thread to start troubleshooting.

[sloopy]

Find someone competent at soldering, and have them socket the whole board... most likely problem is bad ram... do they say 'MT' on them? if so then it a good chance to be bad ram...

 

sloopy.

[kogden]

By just stacking on new RAM chips, couldn't a defective chip still be causing problems?

 

From what I hear 130XE RAM was pretty dodgy quality half the time anyway. Might be worth it just to get that crap out of there and put it sockets and new RAM. Even if it's not the problem now, there's a good chance it might be later.

[kurtm]

Well, for those who routinely work with this machine:

 

I've got one unit, in my vault, which happens to be a "rescue".

 

After finishing a full exterior & keyboard restoration, as well as inside cleaning (without any further tampering or intrusion past shields, etc.) I decided to turn it on, and instantly found a GREEN-SCREEN with absolutely no other activity.

 

This is a short summary of my troubleshooting efforts, so far (and no success):

 

1. Inserted Star-Raiders in cart slot (which boots immediately), and nothing (just green screen).

2. Machine has 16x 4164 chips. Placed 8x new on TOP of the existing ones (one-by-one, and then all eight, carefully aligned), column by column. No luck.

3. For the heck of trying, placed NEW rom (61598B) on op of existing one (just in case)... nothing.

4. Left on for 20mins, checked temperature: ram-bank slightly warm (both-columns), CPU hot, GTIA warmer, and the rest seems slightly warm (nothing weird).

5. CPU and GTIA seem socketed. Replaced both with new units, and exactly the same F-green screen.

6. Checked some basic signals (around MMU) like Halt, reset, R/W, etc, and could not see anything strange on the scope (but nothing formal to compare against, though).

7. Could not test (piggy-back) the 24947 because don't have a spare one... nor I am going to open-up my 800XL just for this...

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

Any tips or additional troubleshooting suggestions would highly appreciated.

 

I don't see any power supply check there. You sure this is a good power supply?

[feather]

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

130XE 16*RAM: http://www.freespace.com.au/filehosting/34001

[Faicuai]

Well, for those who routinely work with this machine:

 

I've got one unit, in my vault, which happens to be a "rescue".

 

After finishing a full exterior & keyboard restoration, as well as inside cleaning (without any further tampering or intrusion past shields, etc.) I decided to turn it on, and instantly found a GREEN-SCREEN with absolutely no other activity.

 

This is a short summary of my troubleshooting efforts, so far (and no success):

 

1. Inserted Star-Raiders in cart slot (which boots immediately), and nothing (just green screen).

2. Machine has 16x 4164 chips. Placed 8x new on TOP of the existing ones (one-by-one, and then all eight, carefully aligned), column by column. No luck.

3. For the heck of trying, placed NEW rom (61598B) on op of existing one (just in case)... nothing.

4. Left on for 20mins, checked temperature: ram-bank slightly warm (both-columns), CPU hot, GTIA warmer, and the rest seems slightly warm (nothing weird).

5. CPU and GTIA seem socketed. Replaced both with new units, and exactly the same F-green screen.

6. Checked some basic signals (around MMU) like Halt, reset, R/W, etc, and could not see anything strange on the scope (but nothing formal to compare against, though).

7. Could not test (piggy-back) the 24947 because don't have a spare one... nor I am going to open-up my 800XL just for this...

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

Any tips or additional troubleshooting suggestions would highly appreciated.

 

I don't see any power supply check there. You sure this is a good power supply?

 

...Good point, but it is checked (both on the Scopemeter, as well as firing up my 800XL, with absolutely no hesitation or problem).

 

Thx.

[Faicuai]

Find someone competent at soldering, and have them socket the whole board... most likely problem is bad ram... do they say 'MT' on them? if so then it a good chance to be bad ram...

 

sloopy.

 

...I can de-solder and re-solder the entire MoBo + sockets (have all the tools, although it would have to be done bit-by-bit, on my spare/weekend time). I have already performed some critical / high-precision repairs, including Indus-GT LED-display de-soldering and re-soldering for substitution purposes.

 

However, I expected to conduct a more structured/educated diagnostic, and try to pinpoint the problem before embarking in such time-consuming process.

 

In any case, and after spending some time with the machine's inner making, I can clearly see the Tramiel legacy: cheap components, cheap board mounting-and-soldering (e.g. long protruding and bent through-pins, on the back side, almost no clearance between between such and the shields, rust-prone conductors / pins from enhanced cart. terminals, etc.

 

The keyboard, however, is such a bizarre (and surprising) piece of work: I can't imagine how the intricate molding, fixtures and multi-part keys (+silicon "implants") and its supporting metal-plate could actually be cheaper than its XL-series relatives... Maybe the Cheapo-Tramiels cut a volume-deal with the same manufacturer of the ST-line keyboard (very similar).

 

In any case, I can't help but feel an overall sense of "crudeness", all-round, when carefully looking at this machine's craftmanship and finish (it may be only me, mind you...)

 

This one will certainly needs lots of TLC (tender-loving-care) before it comes close to my 800XL...

[Faicuai]

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

130XE 16*RAM: http://www.freespace...lehosting/34001

 

THANKS (!!!)

 

Not a service manual but a very nice-work on rendering high-quality schematics. I will try to use these as some guidance for checking / comparing common signals at different chips, and overall path-conductivity (don't know what could be really broken).

[sloopy]

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

130XE 16*RAM: http://www.freespace...lehosting/34001

 

THANKS (!!!)

 

Not a service manual but a very nice-work on rendering high-quality schematics. I will try to use these as some guidance for checking / comparing common signals at different chips, and overall path-conductivity (don't know what could be really broken).

 

RAM, need to test it first...

 

sloopy.

[Welsh Wizard]

have a look here

http://www.atariage.com/forums/topic/171583-error-codes/page__p__2125391#entry2125391

[feather]

If the RAM is okay check MMU (U3).

[kurtm]

I don't see any power supply check there. You sure this is a good power supply?

 

...Good point, but it is checked (both on the Scopemeter, as well as firing up my 800XL, with absolutely no hesitation or problem).

 

Thx.

 

Yeah, just wanted to check. Initially your new profile photo made me miss that it was you asking. But then I figured we all overlook the simple things sometimes

[Faicuai]

 

(...) your new profile photo made me miss that it was you asking. But then I figured (...)

 

 

...I found that odd, too. Anyhow, the devil is on the details.

[sloopy]

My profile image stopped working also, that why i changed it... this was the only image i could get it to accept... had another nice Atari 800 image to use too :'(

 

and for those that dont know, this is an image of a test program for VBXE from draco030...

 

sloopy.

[kurtm]

My profile image stopped working also, that why i changed it... this was the only image i could get it to accept... had another nice Atari 800 image to use too :'(

 

and for those that dont know, this is an image of a test program for VBXE from draco030...

 

sloopy.

 

That is quite unfortunate. I'm pretty sure that image had a large fan base

[Faicuai]

(...)

That is quite unfortunate. I'm pretty sure that image had a large fan base

 

 

Indeed.

[russg]

Well, for those who routinely work with this machine:

 

I've got one unit, in my vault, which happens to be a "rescue".

 

After finishing a full exterior & keyboard restoration, as well as inside cleaning (without any further tampering or intrusion past shields, etc.) I decided to turn it on, and instantly found a GREEN-SCREEN with absolutely no other activity.

 

This is a short summary of my troubleshooting efforts, so far (and no success):

 

1. Inserted Star-Raiders in cart slot (which boots immediately), and nothing (just green screen).

2. Machine has 16x 4164 chips. Placed 8x new on TOP of the existing ones (one-by-one, and then all eight, carefully aligned), column by column. No luck.

3. For the heck of trying, placed NEW rom (61598B) on op of existing one (just in case)... nothing.

4. Left on for 20mins, checked temperature: ram-bank slightly warm (both-columns), CPU hot, GTIA warmer, and the rest seems slightly warm (nothing weird).

5. CPU and GTIA seem socketed. Replaced both with new units, and exactly the same F-green screen.

6. Checked some basic signals (around MMU) like Halt, reset, R/W, etc, and could not see anything strange on the scope (but nothing formal to compare against, though).

7. Could not test (piggy-back) the 24947 because don't have a spare one... nor I am going to open-up my 800XL just for this...

8. Could not find / download a Service Manual specific for the 130XE (my original 800XL copy does not seem to help).

 

Any tips or additional troubleshooting suggestions would highly appreciated.

'8. Could not find .... Service Manual...'

Sam's Computerfacts is still available for the 130XE,.... for $20 and you can download it. I have one, but it has multiple page pictures and schematics that wouldn't be easy to scan.

 

https://www.samswebsite.com/en/photofact/search/index/brand/ATARI

Edited April 7, 2012 by russg

[atari8warez]

By just stacking on new RAM chips, couldn't a defective chip still be causing problems?

 

From what I hear 130XE RAM was pretty dodgy quality half the time anyway. Might be worth it just to get that crap out of there and put it sockets and new RAM. Even if it's not the problem now, there's a good chance it might be later.

 

Stacking a working ram chip on top of a bad one works, I have diagnosed several chips successfuly that way...

[atari8warez]

My profile image stopped working also, that why i changed it... this was the only image i could get it to accept... had another nice Atari 800 image to use too :'(

 

and for those that dont know, this is an image of a test program for VBXE from draco030...

 

sloopy.

 

I've seen that exact same pattern on my digital LCD panel today when I was fast forwarding Jurassik Park on my VCR.... Yeah, I am selling my decades old Hithachi VCR, so wanted to see it's still working. Remember paying $750 for that device years ago... I guess that's why it still works :-)

[+bob1200xl]

That may have worked for you, but it is not a valid diagnostic technique for RAM or any other chips.

 

A lot of the things we do may work for us and yet be bad advice for a novice. They can try some of these things if they really are stuck as long as they are aware that they are way out in the swamp...

 

Bob

 

 

By just stacking on new RAM chips, couldn't a defective chip still be causing problems?

 

From what I hear 130XE RAM was pretty dodgy quality half the time anyway. Might be worth it just to get that crap out of there and put it sockets and new RAM. Even if it's not the problem now, there's a good chance it might be later.

 

Stacking a working ram chip on top of a bad one works, I have diagnosed several chips successfuly that way...

[atari8warez]

That may have worked for you, but it is not a valid diagnostic technique for RAM or any other chips.

 

A lot of the things we do may work for us and yet be bad advice for a novice. They can try some of these things if they really are stuck as long as they are aware that they are way out in the swamp...

 

Bob

 

 

By just stacking on new RAM chips, couldn't a defective chip still be causing problems?

 

From what I hear 130XE RAM was pretty dodgy quality half the time anyway. Might be worth it just to get that crap out of there and put it sockets and new RAM. Even if it's not the problem now, there's a good chance it might be later.

 

Stacking a working ram chip on top of a bad one works, I have diagnosed several chips successfuly that way...

I fixed 3 computers (2 x 130XE and 1 x 800XL) with the piggybacked RAM method, so I would say it works. Do I think it's the best way to diagnose a RAM problem? No, but without owning expensive diagnostic equipment that may be the ONLY way to do it.

 

I am not advicing anybody to do it my way, I am just making my experiences known in the hopes of helping somebody, perhaps you can provide a better method.

[Faicuai]

That may have worked for you, but it is not a valid diagnostic technique for RAM or any other chips.

 

A lot of the things we do may work for us and yet be bad advice for a novice. They can try some of these things if they really are stuck as long as they are aware that they are way out in the swamp...

 

Bob

 

 

...Well, in pure technical / theoretical terms, I not only agree with you, but I am also fully aware of it.

 

The thing is that, before I go crazy and start desoldering chips "like-a-chimp", from a crappy/poorly-made MoBo, it is probably a good idea trying out some basic tricks that would give a hint of where the problem could be.

 

Not long a go, a came accross an otherwise nice 800XL that had a serious failure on its video-output circuitry. It turns out that by combining SuperSalt with rolling my finger across the Luma-processing chip's legs, I has able to correct a good chunk of the problem, which immediately motivated me to bring the Scope, service manual, buy the parts, and the rest of the tools to perform a full and complete troubleshooting. It turns out that the problems were SPREAD accross two different locations, but, nevertheless, the machine was succesfully repaired. I even remember placing the new luma chip on top of the other, before soldering, and VOILA! I knew I was on the right direction.

 

Having said that, there is obviously no substitute for a full, tools-powered troubleshooting and repair.

[+bob1200xl]

Many people read these messages that have few electronic skills. If you know what you are doing, no problem. If you do not, be aware of the validity of the process.

 

Even swapping ICs completely is no guarantee of a fix. The system may function, but the IC you replaced is not 'bad'. Something else may be making the circuit run out of spec and all you did was put in a component with different electronic parameters. You can then trade a solid failure for one that fails only on Tuesdays...

 

Bob

[sloopy]

I am going to have to agree with Bob on this, stacking IC's will only troubleshoot a few fault modes of DRAMs and 74xx's... there are many more then those few, that it wont find, or even will destroy the piggybacked IC... any IC with a 'stuck bit', would fail the piggyback test, complete replacement with good IC's is more reasonable method of testing, short of having proper test equipment.

 

A scope is as close as a simple circuit on a sound card on your PC, so 'cost' isnt a big issue, and this can show many issues with IC's... (note: not all failures will be detectable with this setup, but many will...)

 

sloopy.