My 1050 just died!

[Sid Pokey]

In my ongoing mission of bringing my Atari gear back into use, all was looking good. Sadly, I spoke too soon…

 

After getting my 800XL back up and running with its new SDrive Mini, I was happy to see the 1050 also still works. It's not something I'd want to use very often - that's what the SDrive is for now - but it's nice that I can still access my old floppies for that ultimate nostalgia fix.

 

However, in short, for one glorious moment, both the 800XL and its 1050 floppy drive lived, just like it was 1986. And then before my very eyes, it was all over. The 1050 was dead!  😪

 

And the longer version:

 

For a couple of times, the 1050 worked. Then a few days later, turn it on and it went haywire. I don't remember exactly what what it did, but it certainly wasn't normal behavior.

 

Quickly turned it off and took it apart so I could see what was happening inside. Unfortunately though, this time I powered it on, nothing happened. Power light on, but no activity.

 

I'm sure I tested the power supply previously, and I can only assume I saw nothing of concern. Tested this time though, and without load, it's putting out about 11.5v. That's not normal… right?

 

Does this behaviour sound familiar to anyone? What would be the most likely thing to have fried?

 

Looked at the circuit board and can see nothing obvious. Photos attached.

 

I do actually have another broken 1050 - that one stopped working decades ago - so maybe I could make a good one out of the two. But to do that, I need a replacement power supply first. Finding an AC one seems to be problematic though.

 

What's the latest best option for modern replacement 9v AC power supplies for a 1050 readily available in UK?

[_The Doctor__]

How about checking the voltage regulators inside the drive and making sure everything is clean including drive select switches and all moving parts are cleaned/lubed.

[spookt]

Nice looking 1050 and looks

like a US Doubler too. @_The Doctor__’s suggestion is a good one re checking the 5v and 12v regulators’ output first. 
 

I seem to have a habit of fixing 1050s. I’ve worked on a quite few. Replacement PSUs can be found. Anything the puts out 9v AC at 2 or more Amps is good.
 

What level of fault finding experience do you have and what tools on hand? Multimeter etc? There are service manuals around to help with diagnostics if you search the forums, plus plenty of experience.
 

If you’re looking for spares in the UK drop me a PM and I’ll see what I’ve got on hand. 

[Peri Noid]

Seconed. I bought a 1050 last week. It had the same symptoms - red led on, nothing else. I checked the voltages getting out from 7812 and 7805 regulators - the latter was OK, the former - no output. So... is the regulator dead? The meter was showing a dead short on a 12V rail. But it was not the regulator - it was a dead capacitor, that was shorting this line. I replaced it and the drive works as new.

 

So - do what @_The Doctor__ suggested, test the outputs of voltage regulators and then we will see.

[Sid Pokey]

4 minutes ago, spookt said:

What level of fault finding experience do you have and what tools on hand? Multimeter etc?

Not that extensive I'm afraid, and only basic equipment; multimeter, soldering iron, chip puller.

 

But before I do anything, I need to confirm whether the power supply is the problem. To clarify, is 11.5v unloaded abnormal for a 1050 power supply?

 

If so, will need replacement, but struggling to find one. Search for 'Atari 1050 power supply' and you get old 1980s ones. Search for 'power supply 9v AC' and you get AC-DC ones.

 

Ayway, thanks for replies so far.

[Peri Noid]

17 minutes ago, Sid Pokey said:

To clarify, is 11.5v unloaded abnormal for a 1050 power supply?

It is perfectly normal. Of course, it should be an AC PSU (if it's original then it's deffinitely OK).

[blacka013]

Where are you based in the UK Sid Pokey?

 

If you are in the North, spookt might be able to help you if you don't feel confident tackling the work yourself. If in the South I'm in Lincolnshire so will be nearer to you.

 

Keep us informed on your progress.

 

Regards

 

[xrbrevin]

i had one that did that, it was one of the smaller electrolytic caps that became a dead short

also worth checking the heatsink - if it gets uber hot then check regulators

[macsonny]

It's a process of elimination. I've not restored about a dozen 1050 drives and there's always something unique about each drive, well, virtually always 🙂

 

You're got some good advice above. Check the voltages first. About 1/3 of my drives had issues because of bad power circuitry. My default for any of these drives is to replace both power regulators and also the three large capacitors. I know often they don't need it, but I know eventually they will so I just get proactive.

 

I know this seems a little weird, but a good clean of the drive head rails and a re-oil helps. Turn the drive motors and ensure you've not got any "stuck" motors which I've had a few times now. Also, give the heads a good clean with IPS and a few cotton buds.

 

Also, I've had a few drives where the drive ID selector on rear gets a little dicey. Some Dioxit on the switch and 30 seconds of manipulating the switches helps free everything up and get good contact so the right drive number is selected.

 

Once you get the drive spinning up with a floppy we can then work out if you are having any read errors from there. But first, just getting it to the point of spinning up.

 

FYI - every drive is salvageable. Stick with it and you'll get there 🙂

 

Hope this helps.

 

Edited June 6 by macsonny

[+kheller2]

5 hours ago, Sid Pokey said:

 

 

If so, will need replacement, but struggling to find one. Search for 'Atari 1050 power supply' and you get old 1980s ones. Search for 'power supply 9v AC' and you get AC-DC ones.

 

That's because its a transformer and transformers which are made up of copper and iron haven't changed much if at all since the 80s.  No magic parts in the brick, just wire and maybe a fuse.

[TZJB]

16 hours ago, Sid Pokey said:

Not that extensive I'm afraid, and only basic equipment; multimeter, soldering iron, chip puller.

 

But before I do anything, I need to confirm whether the power supply is the problem. To clarify, is 11.5v unloaded abnormal for a 1050 power supply?

 

If so, will need replacement, but struggling to find one. Search for 'Atari 1050 power supply' and you get old 1980s ones. Search for 'power supply 9v AC' and you get AC-DC ones.

 

Ayway, thanks for replies so far.

 

The Atari 9VAC power supplies will give between 10VAC - 12VAC offload output norminally. This is rectified and stabilised within the Atari 1050 drive as you probably know.

 

The 7805 and 7812 voltage regulators are usually very reliable and can survive a short circuit caused by an old electrolytic capacitor which is often the cause of a failure.

 

The old 1980 Atari 9VAC PSU are very reliable as they are simply fused 240VAC voltage step down transformers. If they can supply 10VAC - 12VAC they are working, if they are not the fuse has blown and will need changing.

 

Next step is to measure the test points TP13 & TP14 for DC output. C69 and C70 can be a cause of failure. When their voltage rating becomes reduced due to age they short circuit.

 

[Beeblebrox]

not had time to skim read the other posts, but i'd defo check the 3 x large caps. They are prone to cold/cracked solder joins on the pads as the legs pass though the pcb. Take the whole board out, flip it over and check on the underside and reflow.

 

Also, obviously check cables for bulging, leaks, discolouration.

 

Be very careful with the caps as they'll be holidng a charge.

 

Also - just to check - at no point have you unplugged or plugged in the sio cable with the drive and/or computer on?

 

 

Edited June 7 by Beeblebrox

[cwc]

18 hours ago, Sid Pokey said:

Not that extensive I'm afraid, and only basic equipment; multimeter, soldering iron, chip puller.

 

But before I do anything, I need to confirm whether the power supply is the problem. To clarify, is 11.5v unloaded abnormal for a 1050 power supply?

 

If so, will need replacement, but struggling to find one. Search for 'Atari 1050 power supply' and you get old 1980s ones. Search for 'power supply 9v AC' and you get AC-DC ones.

 

Ayway, thanks for replies so far.

Source in UK I have used here.

 

Should be AC/AC 9v 3+ Amp:

https://poweradaptorsuk.co.uk/products/3000ma-3a-9v-27va-ac-ac-mains-power-adaptor

 

But I and others here have found AC/AC 9v 2 Amp does the job:

https://poweradaptorsuk.co.uk/products/2000ma-2a-9v-18va-ac-ac-ac-output-mains-power-adaptor

 

 

Edited June 7 by cwc

[leech]

1 hour ago, Beeblebrox said:

Also - just to check - at no point have you unplugged or plugged in the sio cable with the drive and/or computer on?

I always wonder what affects this does, but I'm never brave enough to do it... though I think I accidentally did this while the drive was on, but I definitely always make sure the computer is off.  At least my 1050 was still working during the last test (which was after I installed the happy upgrade).

[Sid Pokey]

OP with clarifications. Thank you to all that have offered advice.

 

Many have suggested a shorting capacitor could be a cause of deadness, but deadness is not what initially happened. Ordinarily, when you switch on a 1050, the head stepper motor will move for a fraction of a second. This time, it went haywire, spinning up and down randomly, despite no disk being in the drive. The deadness only happened afterwards. Wonder then, did I witness the death throes of a capacitor, a rectifier or something else?

 

Anyway, will run some tests soon. When I've figured where it's safe to stick my probe (oo-er).

 

And the suggestion about the drive select switches is interesting. I did move them just before this event cos while I didn't actually get around to it, I was needing to try and get it to work alongside the new SDrive. That will be the first place I'll look.

 

And thank you for advice about the power supply which looks like is not the source of the problem as I assumed.

 

And no, I did not yank the SIO. That would be bonkers! 🤪

[Beeblebrox]

58 minutes ago, Sid Pokey said:

And no, I did not yank the SIO. That would be bonkers

You'd be surprised how easy it is to plug or unplug the SIO cable whilst the drive and computer are on. You can potentially fry chips or components on both devices if you do so. I've done it by accident. 

 

Check those caps and their solder points as well as all the other advice. I am sure you'll fix it. 

 

Also check all cable headers are fully plugged in fully and haven't come loose. 

[Peri Noid]

1 hour ago, Sid Pokey said:

This time, it went haywire, spinning up and down randomly, despite no disk being in the drive.

Oh... The drive reports an error in post check by not responding to commands and repeatedly spinning up and down the drive. It says, there's an error somewhere in the logic section - yet, it's not the PSU nor ROM. It may be the SRAM chip (happens). Or the floppy controller chip (less probable). 

[TZJB]

3 hours ago, Sid Pokey said:

OP with clarifications. Thank you to all that have offered advice.

 

Many have suggested a shorting capacitor could be a cause of deadness, but deadness is not what initially happened. Ordinarily, when you switch on a 1050, the head stepper motor will move for a fraction of a second. This time, it went haywire, spinning up and down randomly, despite no disk being in the drive. The deadness only happened afterwards. Wonder then, did I witness the death throes of a capacitor, a rectifier or something else?

 

Anyway, will run some tests soon. When I've figured where it's safe to stick my probe (oo-er).

 

And the suggestion about the drive select switches is interesting. I did move them just before this event cos while I didn't actually get around to it, I was needing to try and get it to work alongside the new SDrive. That will be the first place I'll look.

 

And thank you for advice about the power supply which looks like is not the source of the problem as I assumed.

 

And no, I did not yank the SIO. That would be bonkers! 🤪

 

You state it went haywire. That would indicate that voltages are good!

 

If the drive is spinning up intermittently then that is an indication of a failed Power On Self Test as @Peri Noid said.

 

I note that your US Doubler has a ROM operating system and that U8, the stacked SRAM, is slightly crooked. Maybe check that it is inserted fully into the socket?

[+kheller2]

I don’t recall the ICD ROM having a POST.  The spin on and off is function of a stock ROM. Unless ICD copied some code….

[TZJB]

15 hours ago, kheller2 said:

I don’t recall the ICD ROM having a POST.  The spin on and off is function of a stock ROM. Unless ICD copied some code….

 

Good point, I don't actually know if the USD has a POST, but I can't explain it otherwise.

 

I couldn't quite be sure of whether the head or disk motor went haywire, but 'spin' implies disk motor.

 

The head should definitely seek track 0 at power on anyway, and if the head went haywire it would step up and down the rails, which involves a RIOT! 😁.

 

Maybe @Sid Pokey could post a video of the drive with the case open and booting up so we can see the head and disk motor behaviour?

 

[Sid Pokey]

1 hour ago, TZJB said:

 

Maybe @Sid Pokey could post a video of the drive with the case open and booting up so we can see the head and disk motor behaviour?

 

No can do I'm afraid. The haywire moment was a once only event of which exact details were not meticulously memorised. After that, it was deadsville.

 

First step to fault tracking was to yank all the chips and contact clean the sockets. Problem is, only the US Doubler chips have come out. The rest are stuck solid. I fear putting any more force on them. Right now, thinking not worth the risk.

 

Will move onto voltage checks another time when I've watched a few YouTube videos.

[_The Doctor__]

using deoxit on the legs and sockets, supporting the pcb fully, push the chips in a few times, deoxit again, put in the fridge. take it back out after and hour or so and let it warm back up.

This will break corroded mechanical crust from the legs and the swipes, then you should be able to pull the chips with a chip puller. Many people use butter knives in tandem to pull chips carefully so as not to damage the trace/components under/around the sockets.

The sockets might be bad based on your descriptions of the chips being immovable. This is the best chance to work them free.

This is where I'd start.

[Sid Pokey]

Another update from OP.

 

For comparison, I got my original 1050 out of storage that stopped working about 30 years ago. They're both rev 1E, both made in Singapore. Oddly though, the original one has a bodge wire connecting the grounds of U14, Q7 and S2.

 

As a matter of interest, any experts know why this might be needed? And as they're the same model, shouldn't the recently failed 1050 have it too?

[Sid Pokey]

3 hours ago, Sid Pokey said:

Another update from OP.

 

For comparison, I got my original 1050 out of storage that stopped working about 30 years ago. They're both rev 1E, both made in Singapore. Oddly though, the original one has a bodge wire connecting the grounds of U14, Q7 and S2.

 

As a matter of interest, any experts know why this might be needed? And as they're the same model, shouldn't the recently failed 1050 have it too?

Another quick update. While they're both rev 1E, it looks like they have different manufacturers; Reliance and what looks like Ciiv? On the latter, all the points connected by the bodge on the other are connected to earth anyway, so assume can rule that out.

 

Been watching a video from Jan Beta on YouTube as he fixes a 1050. Getting some good tips there. Cannot promise I won't have more stupid questions here though. 😉

 

Just like Jan's bad 1050, initial tests suggest the 5v side is probably fine. It's the 12v side that's problematic on both of them. Guessing by the end, as a minimum, I'm looking at a capacitor and regulator replacement. Which might be a bit above my competency, but we shall see.

[+kheller2]

3 hours ago, Sid Pokey said:

Another update from OP.

 

For comparison, I got my original 1050 out of storage that stopped working about 30 years ago. They're both rev 1E, both made in Singapore. Oddly though, the original one has a bodge wire connecting the grounds of U14, Q7 and S2.

 

As a matter of interest, any experts know why this might be needed? And as they're the same model, shouldn't the recently failed 1050 have it too?

can we see a picture of this bodge?