Apple II Europlus Power Supply Failure (ASTEC AA11042C)

[iMic]

Hi everyone, long time reader, first time poster with an interesting one (to me, at least). I apologise in advance if some of my information seems somewhat vague, while I do tinker with electronics and have performed some basic capacitor replacements and other small repairs, I'm still learning here.

I have here an Apple II Europlus, essentially a 220-240V version of the US delivered Apple II+. The PSU doesn't appear to be the factory unit, and was likely retrofitted from an Apple IIe in 1982 as the covers reference the Apple IIe and the copyright date on the PSU varies from the copyright date on the machine itself - 1982 (PSU) to 1979 (entire machine).

It's worked beautifully for several years, and today I decided to take it down from its shelf and try it out for the first time in quite a while. It ran fine for a while, but started to produce an almost hissing sound after about half an hour. I thought it was the floppy disk drive accessing, otherwise I would have shut it off there and then.

A few seconds later, I heard the trademark "POP" of a PSU in its death-throes followed by a cloud of acrid smoke.

I suspected a vented capacitor at first, but when I took the covers off I found the fuse blown, and something a little less familiar to me. (If I haven't already sounded amateur by now, here's where it gets good.) Something exploded, but I'm not quite sure what I'm looking at.




This gold-coloured component has cracked around several edges and thrown out a gold-brown coloured fluid, although I suspect it's been leaking for some time. I cleaned the PCB thoroughly using alcohol in case it could damage traces and joints. The reason I suspect this isn't a sudden leak is that after desoldering the component, I can see that it's pooled below the component in a sticky mess, even making its way through one of the unused holes in the PCB.

Based on examination of the traces on the underside of the PCB, it appears this component is the very first component in the AC circuit, after the plug and power switch.






Many of the component's markings have been destroyed when it failed, but I can see 0.47uF 250V. The component brand is Rifa. Based on the visible PME 271 M and X markings I believe it to be an EMI Suppression Capacitor.





A nearby component, which appears to be similar albeit with different specs (0.1uF 250V and X2) looks to also be leaking as a dark patch can be seen underneath it.




As I can't see any visible charring or damage to surrounding components, and it looks like it could have been a component failure as a result of old age (these parts are 30+ years old), evidenced by the component exhibiting similar symptoms nearby, is there any chance that a replacement of these two components and the fuse would bring this PSU back to life? Of course it would also make sense to change all of the capacitors at the same time, and I'll likely change the lot if the supply can be revived.

In addition, are these still considered to be current tech or have they since been surpassed by a modern equivalent that could be fitted in its place? My regular suppliers for components don't seem to stock anything of the sort, and I'm not sure whether it's because they are no longer produced, whether I'm searching for the wrong terms, or perhaps my regular suppliers simply don't stock them and I'll have to look elsewhere for them.

In summary:

- 0.47uF 250V / X component has cracked (exploded?) and leaked. This component is the very first component after the power switch - essentially the first component in the AC circuit.
- 0.1uF 250V / X2 similar component nearby also appears somewhat leaky.
- Fuse has blown.

Thanks in advance!

Cheers,
~ Mic.



EDIT: Moments after posting this, I came across this link (http://www.minuszerodegrees.net/failure.htm) which appears to document this exact failure under the section "Line Suppression Capacitor". Looks to be a common issue with old age. Adding the link here to be scrutinised by the professionals here. Just want to gather as much information as possible before I order parts and get to work.

[japlytic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Welcome, iMic!
I find Rifa (and Miniprint) as well as other clear epoxy capacitors to be bad in my experience; if I see any, I replace them.
Modern units should have no problem with fitting, and I believe that the new units (and a new fuse) would restore operation.

[goontron]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

i had those caps fail on my apple 2MBplus, it made a mess of the mainboard and blew the fuse and pulling them fixed it, never replaced them but not replacing them is rather stupid as it will cause errors because of the lack of modern VRM's in the mobo.

[eccerr0r]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Wow, I've never seen X caps or poly caps fail like that (that is a poly cap?)... I thought both X and (especially) Y caps should never fail shorted?

Goontron, what's the apple 2MBplus? Apple II+ or Mac Plus 2MB?

I recalled my Apple II+ PSU failed a long time ago, and I don't remember the failure mode anymore, my dad swapped out a component and somehow got it working again. This was on the order of 3 decades ago...

[ben7]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Wow, I've never seen X caps or poly caps fail like that (that is a poly cap?)... I thought both X and (especially) Y caps should never fail shorted?

Goontron, what's the apple 2MBplus? Apple II+ or Mac Plus 2MB?

I recalled my Apple II+ PSU failed a long time ago, and I don't remember the failure mode anymore, my dad swapped out a component and somehow got it working again. This was on the order of 3 decades ago...

Look online, plenty of people have these fail in these old Apple PSUs.

They just need to be replaced, and all will be fine ...

[PeteS in CA]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Rifa PME271 series X and Y caps use an impregnated paper dielectric. They've been in electronics a very long time, possibly longer than I have. They're very high quality, but like anything, they can fail. The Apple II+ has been around a really long time. I can believe very easily your estimate that what you have is over 30 years old. After 30 years of taking hits from power surges and spikes (I'm guessing) the X caps finally broke down at normal line voltage and !

[cheapie]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

It'll work without them, but nearby radios might not. Note that the modern ones are typically yellow plastic without a clear coating.

Also, nice job on the post there. It's much easier to troubleshoot with clear pictures and good explanations (like yours) than a thread titled "help" where the poster says "i wus usin my conputr n it wnt pop n now it don work".

[RJARRRPCGP]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Hi everyone, long time reader, first time poster with an interesting one (to me, at least). I apologise in advance if some of my information seems somewhat vague, while I do tinker with electronics and have performed some basic capacitor replacements and other small repairs, I'm still learning here.

I have here an Apple II Europlus, essentially a 220-240V version of the US delivered Apple II+. The PSU doesn't appear to be the factory unit, and was likely retrofitted from an Apple IIe in 1982 as the covers reference the Apple IIe and the copyright date on the PSU varies from the copyright date on the machine itself - 1982 (PSU) to 1979 (entire machine).

If they're like AMD, then it would mean it was manufactured in 1982.

(All pre-Palomino Athlons had copyright year "1999", LOL) (Even my 2001s)

[re-atari]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

RIFA caps were used widely in electronics equipment during the 70's and 80's for keeping net pollution out. Back then a spike could easily provoke a computer to lockup, or worse: work unreliably (dropping bits).
Remove both caps, clean the soiled area and replace with MKP types rated at 400V or 630V.

re-atari

[PeteS in CA]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Remove both caps, clean the soiled area and replace with MKP types rated at 400V or 630V.

Regarding the voltage rating, absolutely not! Polyester (MKT), Polypropylene (MKP), or impregnated paper (several Rifa series, and at least one Wima series, if they still make it) dielectrics are all fine. But use AC-voltage-rated, safety-agency-approved safety capacitors!

[goontron]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Regarding the voltage rating, absolutely not! Polyester (MKT), Polypropylene (MKP), or impregnated paper (several Rifa series, and at least one Wima series, if they still make it) dielectrics are all fine. But use AC-voltage-rated, safety-agency-approved safety capacitors!

heed that warning well, where you live (and i used to live) without licensing you aren't suppose even touch the primary side of anything that runs off of mains. but that never stopped us

[iMic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Very helpful information in this thread, thank you to everyone here. I've read through everything here, but where do I start with the replies...

Look online, plenty of people have these fail in these old Apple PSUs.

As it turns out, another Apple collector nearby contacted me as his Apple IIe has done exactly the same thing only a few weeks prior. Thankfully his machine came back to life after changing them over, so it looks very good for mine as well.

Rifa PME271 series X and Y caps use an impregnated paper dielectric. They've been in electronics a very long time, possibly longer than I have. They're very high quality, but like anything, they can fail. The Apple II+ has been around a really long time. I can believe very easily your estimate that what you have is over 30 years old.

I have no doubt the components in this PSU are rather good, but as you said, they are rather old as well. The PSU would likely be around the 30 year old mark, as while this machine is an Apple II+, the PSU label references the Apple IIe. The Apple IIe was manufactured from 1983 to 1993, and the copyright date on the supply references 1982. I'm not sure whether this suggests it's from an early production run or whether they simply never updated the copyright date. Either way, it's getting on a bit.

Also, nice job on the post there. It's much easier to troubleshoot with clear pictures and good explanations (like yours) than a thread titled "help" where the poster says "i wus usin my conputr n it wnt pop n now it don work".

Thanks, I've been around various forums since 2004 and worked as an Apple Technician from May 2010 to June 2013, so I know what's expected by technicians and enthusiasts when trying to help someone troubleshoot an issue. There's so many variables and potential causes for any given issue that a simple "HELP" will never cut it.

If they're like AMD, then it would mean it was manufactured in 1982. (All pre-Palomino Athlons had copyright year "1999", LOL) (Even my 2001s)

It's difficult to tell. The machine is an Apple II+, labelled "Apple Computer Ltd. (c) 1979. Assembled in Ireland". The Apple II+ was manufactured from 1979 to 1982.

The PSU is labelled "Apple IIe Power Supply" and "(c) 1982 Astec Components". The Apple IIe didn't enter production until 1983, and was terminated a decade later in 1983.

Clearly this machine has had an Apple IIe PSU retrofitted at some point, but who knows when that repair was performed.

Regarding the voltage rating, absolutely not! Polyester (MKT), Polypropylene (MKP), or impregnated paper (several Rifa series, and at least one Wima series, if they still make it) dielectrics are all fine. But use AC-voltage-rated, safety-agency-approved safety capacitors!

Noted. I've found some components locally that match the ratings of the old components exactly, and they're only 99c each, so I'll opt for a direct like-for-like replacement.

heed that warning well, where you live (and i used to live) without licensing you aren't suppose even touch the primary side of anything that runs off of mains. but that never stopped us

Always been somewhat curious about that. I know the mains side is a bit of a no-go area, but I've performed a few capacitor swaps and the like to the AC side before. I have a Macintosh 512Ke here that I worked on back in 2010 that had some fairly extensive work done, and it still works perfectly today.

That said I've taken my fair share of hits from 240V mains power before, and the odd charged capacitor, so I learned the safety precautions the more interesting way, I suppose.

[PeteS in CA]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

I have no doubt the components in this PSU are rather good, but as you said, they are rather old as well. The PSU would likely be around the 30 year old mark, as while this machine is an Apple II+, the PSU label references the Apple IIe. The Apple IIe was manufactured from 1983 to 1993, and the copyright date on the supply references 1982. I'm not sure whether this suggests it's from an early production run or whether they simply never updated the copyright date. Either way, it's getting on a bit.

Getting a reasonable idea of when it was built shouldn't be too difficult. In those days Astec had the odd habit of buffing out the part number (and date codes) of their switch transistors. But you should be able to find datecodes on places like the PCB itself, input and output electrolytics, DIP package ICs, and maybe TO-220 package rectifiers.

Frankly, if you're thinking of also refurbishing the P/S, I'd give thought to replacing all the electrolytic capacitors. If you do, don't use O/P capacitors that are too good (e.g. even Nichicon's older PJ series might be too good). Maybe Nichicon's PS series would be reasonably close to the NCC/UCC RX series or Nichicon (1980s) PA series parts that Astec probably used.

Is that P/S a self-oscillating discontinuous flyback design (as was used for the Apple II+ P/S, which was also from Astec)? If there's no inductor(s) on the O/Ps (other than, perhaps some small ferrite core parts for spike noise suppression) it's probably a flyback (where the transformer primary inductance serves as the O/P inductor).

[goontron]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

made an interesting thread on mactalk too.
http://www.mactalk.com.au/62/116421-...ly-failed.html

[iMic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Getting a reasonable idea of when it was built shouldn't be too difficult. In those days Astec had the odd habit of buffing out the part number (and date codes) of their switch transistors. But you should be able to find datecodes on places like the PCB itself, input and output electrolytics, DIP package ICs, and maybe TO-220 package rectifiers.

Frankly, if you're thinking of also refurbishing the P/S, I'd give thought to replacing all the electrolytic capacitors. If you do, don't use O/P capacitors that are too good (e.g. even Nichicon's older PJ series might be too good). Maybe Nichicon's PS series would be reasonably close to the NCC/UCC RX series or Nichicon (1980s) PA series parts that Astec probably used.

Is that P/S a self-oscillating discontinuous flyback design (as was used for the Apple II+ P/S, which was also from Astec)? If there's no inductor(s) on the O/Ps (other than, perhaps some small ferrite core parts for spike noise suppression) it's probably a flyback (where the transformer primary inductance serves as the O/P inductor).

I'll have to take a look inside the PSU to see if I can better pinpoint the date. I'll take a look at the key areas you've suggested, hopefully we can get to the bottom of this. I was thinking of changing the capacitors over as well, although it may be outside of my budget at the moment, but I'll be swapping them over for sure, if not now, then in the coming weeks.

As for the P/S design, that's well outside of my level of knowledge. Perhaps I can take a few photos of the overall unit when I have it apart next though.

made an interesting thread on mactalk too.
http://www.mactalk.com.au/62/116421-...ly-failed.html

MacTalk's my old stomping ground for Apple stuff, a lot of the Vintage Apple collectors I came to know over the years are on there. It's a little quieter there these days than it used to be, but there's still a few around.

[PeteS in CA]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

As for the P/S design, that's well outside of my level of knowledge. Perhaps I can take a few photos of the overall unit when I have it apart next though.

I'm probably BadCaps' resident semi-geezer, and have been working in power electronics a long time. I've actually tested - for competitive comparison - an Apple II+ power supply, including thermocoupling key components and seeing how hot they get when operating under load. With a couple of good pictures I think there are several people here who could recognize the topology of a P/S. In the late 70s and well into the 80s the topology of choice for 100W and under was flyback. The efficiency was a bit low - ~65% - but the simpler, low component count, topology was less expensive (back then, the target price was >/= $1/watt!). The Astec Apple II+ P/S was a self-oscillating discontinuous flyback design that used a TL430 or TL431 (basically a reference with an op-amp) for regulation. This basic topology is still used in some low-power designs.

[iMic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

I would assume it to be the same as the Apple II+ power supply, based on your description. The component count is rather minimal considering its size. I had the supply apart yesterday, but forgot to take some complete PCB shots at the time.


I swapped out the Rifa 250V 0.47 X and 0.1uF X2 capacitors for brand new Suntan 275V 0.47uF X2 and 0.1uF X2 Metallised Polypropylene capacitors. Not the best supplier but readily available locally, so it saved me having them shipped, and definitely functional. The existing components had extremely messy solder joints (as you can see on my last pic in my first post of this thread), which were cleaned up, and one of the traces on the underside of the board needed adhering back to the PCB where it was lifting very slightly.

Overall though, the repair went extremely well.

[ben7]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Good job!

[iMic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

Interestingly, the machine still has that strong "coffee-like" smell of a blown film capacitor in it. I may have to take the system apart and clean it out, but I'll inspect the inside of the PSU again to make sure the new capacitors aren't being destroyed by another fault in the supply somewhere. Mind you, I doubt the new capacitors would use exactly the same fluid inside, so it's likely to be from the ones that failed last week.


Perhaps slightly concerning is that the machine hisses very slightly when powered up, almost inaudible unless your ear is near the PSU casing. This could be normal operation. After all, very few PSUs are truly silent when powered up. It could even be the switch. The full 240V travels through the rear mounted power switch, after all.

What I suspect isn't normal is that the noise becomes louder when my Disk Drive controller card is connected to the Logic Board. It's not a genuine Apple Disk II card, and appears to be a no-name aftermarket. It was pulled from an APCOM Apple II clone a few years ago.

I don't believe the card is shorted or failed, since it was still capable of driving a Disk II floppy drive when it was last tested. Admittedly this was prior to the fireworks of last week. The card itself supplies power from the Apple II's internal supply to the disk drive mechanism, but at this stage no drives are connected.






EDIT: With that card removed, it also looks like the slight vertical lines on the screen (I'm using an LCD) mostly fade. I wonder if that card is introducing some interference into the video circuit. I'll have a look into it later and see if I can grab an audio recording or two of the Power Supply while I'm at it.

[iMic]

Re: Apple II Europlus Power Supply Failure (ASTEC AA11042C)

In regards to the issue I posted above, I may have an idea, but I could be wrong. As it's almost inaudible unless your ear is near the PSU casing, and only when more than one card is installed in the system, I don't think it's anything more than a case of Capacitor or Coil Whine as a result of age. The fewer cards in the system, the lower the total load on the power supply will be. With only the Memory Expansion card fitted, the noise clears up completely. Perhaps a capacitor change may be in its future.


Now, this machine smelled like the inside of a International Roast tin. That capacitor residue smelled like coffee, but not in that pleasant way. The smell persisted after replacing the Line Filters in the power supply, so I decided to tear the machine down and service it, and try to find the source of the smell while I was at it.

It didn't take long. It made a nice outline of the power supply. Also, check out that perished speaker foam. It was like powder.



I stripped the machine down to the bottom pan and scrubbed it down with solvents and cleaners. A few seconds in the solvent and the stuff washed off like water. I sprayed the underside of the Logic Board and around the connectors and chip sockets with circuit board cleaner, but it'll take some scrubbing to remove that caked-on dust around the slots and components.

I removed the speaker foam and replaced it with a single double-sided adhesive foam disc, stuck to the lower pan. Holds in place with no problems.




I did take the keyboard apart and give that a clean out as well, but I didn't take any pictures of that process. Needless to say keyboards are my least favourite part of any computer service. After that was done, the machine was reassembled...




...and powered up for testing.




Impressively, the video quality has improved quite a bit. No more faint vertical lines on the display, only a perfectly crystal-clear image. You try taking a picture of an awful, low quality Twisted Nematic display though.





For anyone that wanted to see the Line Filters in place, I took a quick snap while I had the machine apart. Not much to look at, but you can see it's clearly much better than before.




Interestingly, it also looks like the machine has been modified. One chip has been removed, a chip socket has been stacked on top of the existing chip socket, but with two red and black wires coming off it. Then the existing chip has been stacked on top in a piggyback configuration. The two wires travel up to the keyboard connector, with the black connecting to the second pin from the left, and the red connecting to the third pin from the right (looking directly at the connector from the back of the machine, not the front).




I have no idea what these do, but the keyboard works fine with them disconnected, so I suspect it's a modification of some sort rather than a fix.


Anyway, I think that's about it for now, until I can scrape together some cash to perform a capacitor change at least. With only the memory expansion card fitted, it seems to be running fine and it isn't pushing the PSU too hard. Overall, it's a much happier machine.


Cheers,
~ Mic.