Atari 130XE suddenly went POOF in the middle of game.... capacitator gone? Other tips?

[Rybags]

Output voltage is a function of the number of primary vs secondary windings (a bit more complex in reality but you can reduce the equation to that).

I guess if a winding lost insulation and effectively reduced it's number of turns because of conduction then that could affect it.

Or maybe the PS was a combined 5/12 unit to begin with and somehow the 12V has leaked through into the 5V rail.

[xahmol]

7 hours ago, Rybags said:

Or maybe the PS was a combined 5/12 unit to begin with and somehow the 12V has leaked through into the 5V rail.

This is exactly what my Commodore contacts are saying, and what apparently is the huge risk of using original C64 PSUs…..

(Reason why in every Commodore group every new user is immediately warned in all caps to throw that PSU away)

 

Can not confirm myself as I am an absolute electronics newbie. Just report what I see.

 

Anyway: meanwhile ordered a 800XL and a brand new Keelog aftermarket PSU.

So hope that at least that SUBcart still works…..

[thorfdbg]

The PSU you have here is actually one of the good quality ones, they don't fail that easily. If you measure voltage, please also put some load on it (probably some 100 Ohm or so). Potentially, the output regulator of the PSU went bust (internal short), but that's really relatively rare. I have still two of these units, and they are still good.

 

[xahmol]

11 minutes ago, thorfdbg said:

The PSU you have here is actually one of the good quality ones, they don't fail that easily. If you measure voltage, please also put some load on it (probably some 100 Ohm or so). Potentially, the output regulator of the PSU went bust (internal short), but that's really relatively rare. I have still two of these units, and they are still good.

 

No clue how to put load on it 😉for sure never ever having any retro hardware anywhere near that PSU.

Anyway: the PSU suddenly going bust is consistent with what I saw. Fine a whole morning, and then suddenly indeed a sizzling sound and poof…. Bust. Guess the PSU did not like it to be under full load again after being at the attic of the person that sold it to me for 35 years or so.

 

Edited July 6 by xahmol

[xahmol]

Actually see this post about the exact same PSU.

This guy even got 15V from the same PSU.

 

 

[TGB1718]

19 minutes ago, thorfdbg said:

The PSU you have here is actually one of the good quality ones, they don't fail that easily. If you measure voltage, please also put some load on it (probably some 100 Ohm or so).

No load needed with these, just measured mine off-load and it measured 5.12VDC, it's the AC PSU's that can read high off-load.

[TZJB]

On 7/5/2024 at 4:18 PM, xahmol said:

The promised photo of the motherboard.

 

Your 5V supply giving out nearly 13V is frightening. Sorry that happened to you.

 

This C061763 PSU is repairable though and the diagram is available from http://blog.3b2.sk/igi/post/Napajacie-zdroje-Atari-600XL-800XL-130XE-800XE-65XE-XEGS-Power-supply-Atari-typeIV-part-5.aspx. Google translate is not working for me for this web page. However:-

 

 

 

Apparently the LM723N regulator needs at least a 10.5V supply which is obviously now being passed directly to the output due to component failure.

 

Often the DRAM will fail with an over-voltage, but with the majority manufactured by Micron Technology, which tend to fail randomly, it is normally best to replace them anyway even if they are working, to prevent unexpected results.

 

In my opinion, as all of the capacitors are rated at 16V or more, they should be fine. It's the rest of the chips that will need to be verified after the DRAM has been replaced if it is still non-functioning, normally by substitution into a known working 130XE.

 

I now install a 5V6 5W zener diode directly across the 7 pin DIN power socket J2 pins 6&7 in order to combat this type of over-voltage failure, with the aim of limiting the supply voltage to 5.6V and blowing the time delay fuse of the power supply.

 

In any case you will probably be happier with a 800XL as it is built more robustly and the cartridge port is more accessible. SUBCART will also expand the memory with the PBI cable connected and configured, and I also hope your SUBCART still works.

[Chri O.]

Bummer huh my power supply recently decided to go poof but lucky never went over 5 volts but (3.5 volts).

[xahmol]

8 hours ago, TZJB said:

In any case you will probably be happier with a 800XL as it is built more robustly and the cartridge port is more accessible. SUBCART will also expand the memory with the PBI cable connected and configured, and I also hope your SUBCART still works.

This is actually exactly what I did. Bought an 800XL instead. Already arrived, see photo.

 

Bit did not try it yet, as I am not touching original Atari PSUs anymore 😉A Keelog after market PSU is on its way from Poland, so waiting for that.

 

And therefore also ino clue yet if the SUBcart is damaged as well.

Already contacted its creator. He indicates the FPGA is probably OK, but he was less sure about the ‘level shifters’. He was also worrying PBI and DAC cables. Especially the latter might be safe, but he was not sure. The SIO cable is passive so that one should be OK.

He did offer to help me out if it is damaged. Which is very nice, because obviously the failure is not him to blame. So was already expecting to need to fully buy a new one.

 

But maybe will get that 130XE repaired someday. I really like the design of the XE models.

But now having seen the 130XE on the inside, tend to agree now that the 800XL is build better.

Edited July 15 by xahmol

[TZJB]

15 hours ago, Chri O. said:

Bummer huh my power supply recently decided to go poof but lucky never went over 5 volts but (3.5 volts).

 

The potted variety are normally quite reliable. I am glad that it expired gracefully, obviously just a paperweight now as it would probably be impossible to extricate anything from that lump of resin.

 

I am not sure what circuit this one uses but I am led to believe that it also has a LM723N regulator.

[TZJB]

12 hours ago, xahmol said:

This is actually exactly what I did. Bought an 800XL instead. Already arrived, see photo.

 

Bit did not try it yet, as I am not touching original Atari PSUs anymore 😉A Keelog after market PSU is on its way from Poland, so waiting for that.

 

And therefore also ino clue yet if the SUBcart is damaged as well.

Already contacted its creator. He indicates the FPGA is probably OK, but he was less sure about the ‘level shifters’. He was also worrying PBI and DAC cables. Especially the latter might be safe, but he was not sure. The SIO cable is passive so that one should be OK.

He did offer to help me out if it is damaged. Which is very nice, because obviously the failure is not him to blame. So was already expecting to need to fully buy a new one.

 

But maybe will get that 130XE repaired someday. I really like the design of the XE models.

But now having seen the 130XE on the inside, tend to agree now that the 800XL is build better.

 

This looks like a very good refurbished machine with useful extras.

 

The Atari power supply will have been tested but after your previous experience caution is warranted.

 

I have not heard of the Keelog PSU but it seems to be the most expensive replacement on the market. Lots of people buy this one: https://lotharek.pl/productdetail.php?id=134.

 

I hope all goes well with your SUBCART as I did not realise there were active components in the cables also.

 

Regarding your 130XE, unless you want to gear up with soldering and de-soldering equipment, it might be better to just sell it on as non-functional.

 

Best of luck.

[xahmol]

Update: PSU did arrive, and not only does the 800XL work, also the SUBcart still works!

But also found out that the ECI cable that I bought with it is XE models only, need the PBI version for the XL. So ordered that one.

SIO cable works though.

 

Relieved! Pity of the 130XE, but at least it did not damage the cart as well it seems.

 

And could finally finish that M.U.L.E. long-play recording.

Atari 800XL: M.U.L.E. longplay
https://youtu.be/s2HUjm4E09E

 

(oh, and yes, tried the 130XE with new PSU as well. Completely no video output or any sound. LED funnily does burn).

Edited July 16 by xahmol

[TZJB]

1 hour ago, xahmol said:

Update: PSU did arrive, and not only does the 800XL work, also the SUBcart still works!

But also found out that the ECI cable that I bought with it is XE models only, need the PBI version for the XL. So ordered that one.

SIO cable works though.

 

Relieved! Pity of the 130XE, but at least it did not damage the cart as well it seems.

 

And could finally finish that M.U.L.E. long-play recording.

Atari 800XL: M.U.L.E. longplay
https://youtu.be/s2HUjm4E09E

 

(oh, and yes, tried the 130XE with new PSU as well. Completely no video output or any sound. LED funnily does burn).

 

Thank goodness the SUBCART survived.

 

It is generally best to buy all the cables on purchase of an AVGCART or SUBCART, just in case it is connected to an alternative machine.

 

As the SUBCART is still working, this might mean all but the DRAM survived in the 130XE after the over-voltage as all major components are fed from the same +5VA rail.

 

Generally the DRAM draws so much current they might protect the rest of the components, except maybe FREDDIE which manages the DRAM. Shame the fuse didn't blow in the PSU.

 

When powered by the new PSU, does the DRAM of the 130XE get hot now? Do they have 5V across pin 8 and 16?

 

Your 130XE LED has a R95 1 kOhm current limiting resistor, which can allow a large voltage variation before the LED draws too much current, which may explain why it still operates.

Edited July 16 by TZJB

[xahmol]

27 minutes ago, TZJB said:

When powered by the new PSU, does the DRAM of the 130XE get hot now? Do they have 5V across pin 8 and 16?

Might try one day. Issue is that I am such an electronics n00b that drawing any conclusions would be difficult for me as I do not know what is normal….

Better let somebody who knows what he is doing have a look.

And knowing myself, probably won’t sell it either. Sincerely detest the hassle of selling stuff, even if sold as not working. Rather keep it for just the looks until I get it serviced some day.

Edited July 16 by xahmol