Retrochallenge meets WOzFest – Check Your Caps!

Retrochallenge 2017/04 is almost over!

WOzFest PR#6 has now started!

It’s time for the two parts of my retrocomputing life to collide in the most resourceful of ways…

My “europlus Refurbapalooza”, whereby I’m trying to get all my europluses operational, has been the thrust of my two Retrochallenge entries in 2016/10 and 2017/04. With the vagaries of “real life” impinging more the second time around (just that time of year, I think), I’ve gotten even less done this month…but that doesn’t mean I’ve been entirely unproductive.

I’ve been able to test the electrolytic capacitors in all seven of my europlus Astec AA11040C power supply units (PSUs). Despite 14 electrolytic capacitors per PSU (so 98 total) and the PSUs being at least 35 years old, I was pleased to find only four capacitors are exceeding (or almost exceeding) their maximum ESR (Electrical Series Resistance) value.

I’m also going to follow the general guideline to replace the C1 filter capacitor, even if the original hasn’t blown (two of the seven originals have definitely blown, and a further three or four are showing cracking in their plastic covering). I’ve bought all the replacement capacitors I need, and hope to install them all and test the PSUs during WOzFest PR#6.

While carrying out these ESR tests, I wanted a ready-reference to the capacitor specifications for determining the correct ESR value to be testing and for when I came to purchase replacement capacitors.

As a non-expert, I also wanted a reference to the position and polarity of the solder points for each capacitor on the underside of the PSU circuit board – I was testing the capacitors “in-circuit” rather than removing them for testing (while not ideal, I’m trying to keep the task manageable).

I had found online a scan of a 1982 document from Apple which provided a great start to what I wanted. It has schematics and circuit board layouts for several Apple PSUs, as well as a components list for each of the PSU models it includes.

Although it has info on the AA11040B (while I have AA11040Cs), upon inspection I believe the primary difference is the AA11040C is the 230V version of the AA11040B with the “115V Select” wire removed and a 250V/2A fuse replacing the 125V/2.75A fuse.

So I decided to prepare just the sort of ready-reference I would have liked to have started with. Over several iterations to refine the design and info included, and taking input from enthusiasts with more PSU repair experience than me, (thanks Mark, Martin, Jon, Geoff and John!), I’ve created the “WOzFest Labs Apple Astec Power Supply Unit AA11040B/C Electrolytic Capacitor ‘Spec & Check’ Sheet” (it just rolls of the tongue!) – and I’m pleased to announce the release of v1.0 of this “Spec & Check” sheet for use by other enthusiasts looking to test and refurbish their AA11040B/C PSUs.

This release is the major result of my Retrochallenge 2017/04 entry and in line with WOzFest PR#6’s theme of “Preservation”.

I’ve designed the sheet so that it can be printed at 100% on A4 (297✕210mm) or US Letter (8.5″✕11″) without any information being cropped. When printed at 100%, the picture of the underside of the PSU circuit board is “life size”, so it’s easy to correlate the highlighted solder points to a physical circuit board.

The sheet can be used as a checklist of capacitors that are in or out of spec, has the maximum ESR values listed for each capacitor (as well as other specs) in both tabular and “call out” forms, and the polarity of the solder points are annotated and colour-coded.

This is only v1.0, and suggestions/corrections from other enthusiasts will be included in updates. If I’m able, I’ll also release versions for other PSU models that Apple used in Apple ][s.

This is the first resource issued under the name “WOzFest Labs”, and hopefully there’ll be many more (I’ll probably re-release my Silentype Font under that name, too). I’d be interested in collaborating on other resources, too, so hit me up if you have any ideas you”d like to work on with me.

A few notes:

  • I’ve provided specs and solder points for the C1 filter cap to ease replacement of this component along with any out-of-spec electrolytic capacitors;
  • Capacitors C13 and C14 are in parallel on the circuit, so testing either one to half the usual maximum ESR is adequate when testing them “in-circuit” – if capacitors are removed for testing, double the stated maximum ESR value for these two capacitors;
  • Capacitors rated to 105°C are recommended;
  • The 1982 document from Apple has at least two errors in the components list for the AA11040B PSU, so check its information carefully if you’re using it as a reference.
  • If you’re wondering about the typewriter-like font I used, it’s Prestige Elite, which, by my reckoning, is the font used in early Apple spiral-bound manuals such as The Applesoft Tutorial. It’s my theory that these early manuals were “typeset” using material printed by the ubiquitous IBM Selectric typewriter.

So, other than some soldering, testing and writing a recap on my re-capping adventures, that’s pretty well it for my Retrochallenge entry this time around. I’m looking forward to getting to the meat of my europlus refurbishment – testing (and hopefully repairing) motherboards – next go ’round in October!

Retrochallenge 2017/04 Half Time Report: Nothing to Report, Captain

As I feared, the greatest challenge I’m facing this month is doing anything retro-related, including an on-time half time report!

The Man Cave has been in dire need of some organisation, and I got to spend Good Friday at least processing the mess on the table tennis table: it can now serve as my workspace when I get to my first task, a PSU checkup.

At least the PSUs have all been cracked open during Retrochallenge 2016/10, and I’ve borrowed an ESR meter off Jon from Manila Gear to assess the health of the PSU capacitors.

Being able to check each capacitor type across all PSUs at the same time will be quite a time-saver, I think.

With WOzFest PR#6 fast approaching, I’ll likely have to limit my Retrochallenge work to the PSU health check, but if at all possible, I’ll try and get to other items on my europlus refurbishment to-do list.

Perhaps April isn’t such a good time of the year for me and October is my sweet spot – I guess we’ll find out in six months’ time!

Retrochallenge 2017/04 Entry: europlus Refurbapalooza Revisit

It’s time for real life to get in the way of my retrocomputing hobby in a structured way again, so I’ve officially entered Retrochallenge 2017/04!

And what better way to celebrate “unfinished business” than to return to my Retrochallenge 2016/10 entry with a “europlus Refurbapalooza Revisit”?

I got what I generously call a “heap” done last time, but I still have a different “heap” to do!

I have rubber feet to apply.

I have power supplies to test.

I have cases to swap.

I have motherboards to test.

I basically have more on my list than I should reasonably expect of myself when trying to get more renovations work done (shhhhhh!) and WOzFest PR#6 to prepare for!

But if I don’t enter, I won’t have entered…or “something something inspirational”, anyway – I do know I would be unlikely to do anything retrocomputer-related (other than WOzFest prep) if I didn’t enter, and no-one wins in that scenario (spouses and renovations excluded).

So, harass me for updates if I’m silent, goad me for more if I’m under-performing, celebrate my wins with me, commiserate in times of adversity, but whatever you do, enter Retrochallenge 2017/04 with me!

More europlus Census Info!

Hold the presses! OK, so this is too late to count towards my Retrochallenge entry, given that October is so well and truly over, but I have a little bit of extra info for my europlus census…

This is an object lesson in revisiting assumptions, or at least periodically checking on things you were told when your knowledge base meant you took that information on face value.

I was gifted a motherboard at WOzFest ][, and was told at that time is was an Apple ][ motherboard, not a Apple ][ plus/europlus motherboard. I was intending on using it to replace a clone motherboard in a lidless case I had and trying to get a pre-plus system going.

Some time was spent at WOzFest /// trying to get it running without success – but we didn’t have the time and resources on the night for this project. It ended up being a “some day” project and the board has been shuffled around the Man Cave while I’ve been doing other things, and without any close attention paid to it.

Fast forward to last night and while chatting in the Man Cave with Jon from Manila Gear about troubleshooting my a2heaven VGA Scaler Card, we got to talking about motherboard revisions and layout. The board was out so I looked at it to see how different an Apple ][ board was to the various europlus boards…

…and noticed the (not so) minor fact that it’s another RFI europlus motherboard date stamped 1882! If I’d even just looked at the date stamp previously I would have realised this wasn’t a pre-plus motherboard.

Given it’s case-less, that means I have more spare europlus parts than I thought, but we can never have too many of those as our systems age, can we?

So I need to make a minor addition to my europlus census as follows:

Serial numberDate CodeCPUNotes
IA2S2-669150no date code65C02wrong (apple ][plus) lid
IA2S2-667843518265C02no speaker or joystick socket
IA2S2-700105418265C02
IA2S2-67133081186502
IA2S2-61449482376502previously no label
IA2S2-65367781316502
IA2S2-67643381096502no PSU
18826502bare board

As previously mentioned, the mix of serial number vs motherboard vs PSU will change once I’ve gotten six boards working (for the six complete europlus cases I now have) – having eight europlus motherboards will make the task of getting six working that much easier. And I still have a clone motherboard or two for chips as well.

So I’m hoping I now pay a little bit of extra attention to my collection as I sort it, in case there are any other gems in there.

Let me know in the Comments below if you’ve ever “discovered” something hiding in plain sight in your collection you wish you had noticed earlier.

europlus Refurbapalittle – Retrochallenge 2016/10 Recap

OK, it’s “Tools Down” for Retrochallenge 2016/10!

As previously mentioned, this was my first Retrochallenge entry.

I’d noticed the frequent lament of Retrochallenge entrants about real life impacting on significant progress on entries, so I feel I entered with my eyes wide open on that front.

Whether that meant I didn’t work as hard as I might otherwise have, or that I had realistic expectations of what I might achieve, I’m not quite sure. With ongoing renovations, I like to think the latter is the case.

The bottom line is I did not complete the tasks I originally envisaged for refurbishing all of my europluses…but this month has been anything but a wasted effort, and I’ve certainly achieved a lot more than if I hadn’t entered.

For example, I likely wouldn’t have spent a day driving to our national capital to pick up two extra europluses if I wasn’t documenting the ones that I had. The chance to secure an extra two machines to go towards my collection and refurbishing efforts (well, one complete machine and one for spare parts) was an opportunity I felt I couldn’t pass up.

I almost certainly wouldn’t have paid so much attention so soon to the look of the motherboards and noticed my new favourite europlus, a motherboard from very early in the europlus’ production run. And, of course, I now have a good idea of the vintages of all my europlus motherboards, which will help me align them with their base plate serial numbers and PSU serial numbers.

Speaking of PSUs, I have now brought together all six gold Astec PSUs I have after removing them from the cases they were in (or grabbing them from my shelves if they were already removed) and I’ve opened them all up in preparation for testing their capacitors. I’ve also discovered that 110V PSU cases were repurposed/relabelled for use in europluses – I’m hoping one day to get more info on this.

While testing the PSU capacitors was a part of my original entry scope, I decided to wait until I had all six in the same open state before even considering testing them as I can then test all PSUs’ capacitors at the same time.

If it weren’t for my entry, I wouldn’t have refurbished my Disk ][ drives when I did. This was in preparation for hooking them up to my newly operational europluses at the end of Retrochallenge – I’m obviously not at that stage yet, but it’s nice to know the drives are all operational.

I don’t think I would have bought 6502s nor rubber feet yet – I now have enough of both for all my europluses for when I need them. And I also know the best solvent for removing the gunk left behind by the original adhesive for the rubber feet.

While I don’t have a comprehensive list of which machines are non-functional (nor what their problems are), I now know I have at least one working motherboard (8237). This gives me a good test base for other tasks, such as checking PSUs after testing/recapping, and possibly as a source of known good ICs and ROMs. I’ve also downloaded a copy of a diagnostics disk I can use when I continue my refurbishing work.

Overall, I’m pleased with what I have been able to achieve this month. Yes, I would have liked to be further along, but I am realistic about how much time I can dedicate to what is a hobby while work and renovation commitments are present.

I’m hoping to do a bit more work on my entry scope before WOzFest 5¼″, but I also have a heap of work to turn my attention to for that as I have some very special things lined up for it and it’s less than three weeks away!

Good luck to all Retrochallenge 2016/10 entrants as we enter judging!

To-Dones

Well, at least I was able to follow through with my final list of to-dos!

  • I gathered together like screws into ziplock bags! An easy win for progress!
  • I cracked open the remaining three PSUs! “Pro” Tip*: after drilling the head off the rivet, be sure to push the remaining rivet body into the case so the PSU baseplate can be removed (I found a Torx 8 screwdriver head worked well for this) – once the base is removed you can easily pop the rivet bodies all the way through the rest of the case sides (T8 to the rescue again) to remove them. *If you hadn’t noticed, I’m not really a “Pro”.
  • There’s a very clear winner in the “Solvent Most Likely to Clean Off Apple ][ europlus Rubber Foot Adhesive Gunk After 35+ Years Stakes”, and that winner is methylated spirits (locally known as “metho” [“Australia: the land of nicknames for everything” should be our national slogan]). Isopropyl alcohol didn’t do anything, and I worried that the gunk would get the best of me and my alcohol-fuelled (well, “alcohol-based”, anyway) attempts to rid myself of it – see the pictures below for some before and afters. This is especially happy news as I have a 20L drum of methylated spirits in the Man Cave, so I shouldn’t run out when it comes to cleaning all the gunk off all the bases!
  • My second retro-themed Bulgarian purchase, which arrived last Friday, was a2heaven’s Apple II VGA Scaler – an Apple ][ interface card which provides VGA output for the Apple ][, the Apple ][+, the Apple ][ europlus (yay!), and the Apple //e. It supports both PAL (yay again!) and NTSC systems. I’ll write up a separate post on this card as I work through setting it up – I’ve got it basically working on my known good 8237 motherboard, but I have a glitch or two to sort out and I don’t want to get distracted so close to The Finish Line.
  • I went back to my original test monitor setup with my known good 8237 motherboard – it all worked and booted into the Dealer Diagnostics disk. So something else was wrong when I tested the next few machines which I’ll leave to another day to try and nail down.
  • I’ve returned the donor ROMs and ICs I used while testing motherboards (as reported in my Half Time Report and Little Ray of (Retrochallenge) Sunshine posts). When I do finally get to test my motherboards and swap in components to try and get non-functioning motherboards working, I’ll do a much better job of keeping track of which components I swap to and from where.
  • I’ve not had time to think of anything else to add to my to-do list tonight, and it’s uncertain what I’ll get time to do in the morning beyond my final entry post – but at least I got to do tonight what I wanted to get done, so I’m happy about that.

Boy! Do I wish I was able to dedicate many more such sessions of time to my first Retrochallenge 2016/10 entry.

Well, I’ll leave my (not quite) post mortem to my final Retrochallenge post tomorrow morning.

On the ]HOME Stretch

Well, we’re definitely heading towards the Retrochallenge Finish Line – only 18 hours to go!

I’m hoping to get a few things done tonight and in the morning before the Midnight UTC deadline (we’re UTC+11:00 at the moment). This is partially justifiable as I got more renovations work done over the weekend than I expected, so I’m taking a little time off from those for this last-day push.

I have a few (mostly minor) tasks I’m hoping to get done:

  • Gather together like screws from the europlus disassemblies – they’re all over the place at the moment and I’m just going to use ziplock bags for the moment;
  • Crack open the remaining PSUs – I need to drill out two rivets on each (unfortunately I’m exceedingly unlikely to get to test any of the capacitors in the PSUs);
  • Test solvents to remove rubber foot adhesive from the baseplate – the baseplate is painted, so I’m hoping methylated spirits or isopropyl alcohol will do the trick;
  • Try out my second Bulgarian delivery, which arrived on Friday (details to follow on what should be my penultimate Retrochallenge 2016/10 post);
  • Check what’s going on with my test monitor setup, although that may be less important now my second Bulgarian delivery has arrived (hint, hint);
  • Put back the ROMs and ICs I’ve moved from spare machines – I’ve decided to be more methodical about swapping chips, including documenting what I’ve tested on each motherboard (this will take it outside the scope of this Retrochallenge); and
  • Anything else I can think of that I have time for while I work on the above!

I’m currently reasonably confident of doing all but the last item on that list before the official close of Retrochallenge 2016/10 – let me know in the Comments what’s on your home straight to-do list.

A Little Bit of Persuasion, Not Much Progress

Well, I was right, the third beer was very persuasive and convinced me to battle on and check more machines.

However, I’ve not had much joy, with the next three machines all exhibiting video glitches. The second and third of those are, I believe, booting the diagnostics disk, but the screen image on two separate monitors is patchy. It’s obvious it’s at the same menu system, it’s just that it’s actually illegible.

I’m going to call it a night. I need to check whether the glitches are happening on the (now) known good europlus (motherboard 8237), as I’m beginning to suspect the monitor, monitor cable or even the PSU I’m using to test the machines with.

Troubleshooting where the issue is will have to wait for another day, though – probably after the weekend. At least I’ve gotten something done, so my conscience will rest easy tonight.

A Little Ray of (Retrochallenge) Sunshine

Another short post, another little bit of progress to report…

As per my Retrochallenge 2016/10 Half Time Report, I hadn’t had much luck firing up my new favourite europlus, even after replacing the 6502, the ROMs and several logic chips.

A couple of nights ago I decided to press on with the next machine along on the table tennis table (motherboard 8109, see my Updated Census)…and didn’t get much further. Similar issues to my early motherboard – no boot or garbage on the screen.

This is one of the two I picked up during my Retrochallenge Roadtrip, and is the one with a funny case, umm, “adjustment” (read “butchering”) around the keyboard and a missing PSU, so maybe it was only being used for parts or was a “project”.

I’m not doing deep analysis of the faults at the moment, I haven’t had the time. But, there I was this early Friday evening, listening to the RCR Podcast Episode 139, enjoying a quiet beer with machines behind me screaming for attention and feeling guilty about not doing much on my entry while Head Judge John Linville is saying kind things about my blog posts in his half time report (apparently, I’m a “pace setter” – let’s not talk about what pace, however). So I thought I’d check the next machine along, motherboard 8237.

It booted successfully into the Apple ][ Dealer Diagnostics disk! It passed Motherboard RAM and ROM Test! It passed the Keyboard Test! I found a Silentype Interface Card Test amongst the menu options! (OK, that last one is not related to my Retrochallenge 2016/10 entry, but I have one of those and knowing I can test it is A Good Thing™.)

So, that’s a win (albeit an admittedly small one). Given I’m now enjoying my second quiet beer, I question the wisdom of doing any more Retrochallenge-related work tonight, but I’m sure the third (possibly) quiet beer might talk me ’round.

Let me know in the Comments below what alcohol-fuelled work you’re getting to in your Retrochallenge entry (you did enter, didn’t you?!).

Happy (Rubber) Feet

A very minor update today (and I’m not sure how much I’ll get done over the weekend as I’m supposed to be concentrating on some renovations-related woodworking)…

A parcel arrived from Bulgaria today: 36 rubber feet to replace those on the bases of my europluses.

I bought enough to do nine bases – so I’ll have plenty for the six europluses I’m hoping to totally refurbish and make complete.

Some of the existing feet are missing, some have been replaced with screw-on ones, and some have just migrated over time like some weird micro-scale (Ha! see what I did there?!) continental drift.

I’m planning on removing all the original feet, cleaning the bases of all adhesive residue, and “installing” four feet per base.

The match is pretty good (see Figure 1) – they were advertised as NOS Apple feet, but, given the slight differences, they’re either (likely) later versions than europlus-era, or ones which just happen to be very similar.

Funnily enough, I’m expecting another Apple ][-related delivery from Bulgaria, but the highly appropriate goods description (see Figure 2) on the customs declaration put paid to any thoughts of having hardware to play with before I’d even opened the package.

I hope you get to do more on your Retrochallenge entry this weekend (you did enter, didn’t you?!) than I’m expecting I’ll get to.