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stepleton

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  1. Apple Lisa Video PROM dump

    Also, as you may already know, your Lisa's serial number is kept in the ROM, so you will notice at least some differences from whatever's in that directory.
  2. Apple Lisa Video PROM dump

    I haven't looked too closely at these, but check here? http://bitsavers.informatik.uni-stuttgart.de/bits/Apple/Lisa/firmware/video/
  3. Exciting news: over on LisaList, Al Kossow of the Computer History Museum has announced that Apple is reviewing the source code for the Lisa Office System to see what they can release publicly. Stay tuned for more in 2018...
  4. I'm afraid what I've got is not particularly useful. When I did my last big recapping round, I ordered caps for multiple devices---Lisas, my NeXTs, printers, the ProFiles, and so on. I don't think I could look at my old orders and distinguish which caps were for which machines. Sorry about that. You may find in any case that the caps in your machines are not the same as the ones in mine. If you look at the revision history on this Video Board schematic: http://bitsavers.informatik.uni-stuttgart.de/pdf/apple/lisa/hardware/050-4012-E_Video.pdf you'll see that some revisions involve adding, removing, or changing capacitors. Furthermore, the selection available to me in the UK may not be the same as what you can order where you are. It may be best to make your own list. It's not too hard; for best results, though, take note of the product series identifiers on the caps (e.g. "SME", "LXF", "LXA" for Chemi-Con caps) and try to find the modern equivalent of the same product lines: for example, "SXE" is a low-impedance cap for which "LXV" is a current Chemi-Con replacement. Look for "group charts" like this one to see how different cap product lines are specialised: http://www.chemi-con.co.jp/e/catalog/pdf/al-e/al-sepa-e/001-guide/al-groupchart-e-171001.pdf and you may also be able to find type replacement guides like the one on page 17 of this catalogue: http://www.mouser.com/ds/2/420/al-all-e1001o-150101-531238.pdf Of course Apple didn't just use Chemi-Con---you will also find Nichicon, Rubycon, and Panasonic caps---maybe a few others too. Your replacements should still stick to brands known for their quality. You may already know all of this, but even if you do, I guess it might be nice to spell it out for other readers. For the video board, if recapping doesn't fix certain video problems, you may also want to replace the potentiometers at the top of the video board. Since your Lisa hasn't been used for a long time, I would recommend trying to test the power supply outside of the computer. You will need some beefy power resistors to accomplish this---not large in value, but large in the sense that they can dissipate a lot of power. Here is how I tested my 2/5 and 2/10 Lisa PSUs: https://68kmla.org/forums/index.php?/topic/30781-apple-lisa-doesnt-boot-need-help-troubleshooting/&tab=comments#comment-335026 (I actually wound up using underspec'd power resistors, only keeping the PSU on for a short amount of time. They got extremely hot! I don't recommend this.) If the PSU seems to be generating good voltages, then whack it back into the computer and see if it goes. (With the Widget unplugged, that is.) If you go to the trouble of getting ready to test the PSU, you may as well recap it beforehand anyway, I think.
  5. Did the seller say that it worked? If so, I might just try turning it on, first with the Widget unplugged. (Unplug both cables.) You will need to replace the electrolytics soon (particularly in the PSU and on the Video Board), but I would not expect there to be too much harm in turning it on now if it's been on recently.
  6. I'm not sure from your description, but just as a quick check, do we know that your 2/5 behaves the same way with the other power supply (the one you haven't been trying to diagnose)? Does the other Lisa work with just the power supply you have been trying to diagnose (but with everything else in the "normal" configuration)? It would be strange to me to find three I/O boards with three failed COPS chips, unless there was something about your Lisas that was frying them somehow. I am also not sure that the 2/10 board behaving differently from the 2/5 boards is diagnostic of anything other than the two boards being different, which they are in several respects. Other people here may know better, though. It would be nice if swapping around your PSUs could help us eliminate some possible problems.
  7. That assessment sounds correct to me. For starters, the machine should not just turn on when you plug it in. I'm not quite sure what to investigate next... I assume that when the PSU is plugged in, its +5v standby pin is effectively being shorted to its on/off pin at all times, which accounts for the "instant on" behaviour. Perhaps it would be good to find out why that is... it may be that a fault on the I/O board or the motherboard is to blame, and finding it might supply more clues.
  8. The hundreds-of-volts lines on the PSU are for video circuits that just pass through the PSU to get to the adjustment knobs on the back of the computer. The actual power supply circuitry doesn't interact with these in any way---back on the schematic, you can see that pins 1,2,3,A,B are isolated from all of the other circuitry. If you are getting a +400V reading on any part of the edge connector while the PSU is on the bench (i.e. not in the Lisa) then something very strange is happening. Can you elaborate on what you're trying right now, and where you're taking measurements? --Tom
  9. I ran into similar symptoms as those in the original post: blank screen, hot DOS card, and so on. The only difference is that removing the RAM didn't work. The culprit turned out to be the power cords I was using: one good, standard BS1363 (UK plug) to IEC cord for the monitor, and one NEMA 5 (US plug) to IEC cord for my 6100, plugged into a dodgy UK-US plug adapter. The terrible adapter wound up not connecting the ground pin to anything, and reversing the connections on the two other pins (that is, connecting live to neutral and vice-versa). After disconnecting the monitor from the 6100, I was able to measure 240V, 50Hz (!) between the D shells of the monitor's VGA cable and the VGA adapter attached to the DOS card's octopus cable. Using proper cables for both the computer and the monitor solved the problem. Surprisingly, nothing was permanently fried; I assume that the 6100 was grounding itself through the monitor, but not well enough to run the DOS card normally. Cheap adapters are dangerous. I should have known better, and now I do.
  10. One obvious final thing I still always forget: make sure to defeat the interlock switch on the back of the PSU (near the video adjustment pots) while you're doing these tests. The +5v standby will work whether the interlock is defeated or not; the other rails won't. Just wedging a piece of cardboard between the switch and the housing will do the job.
  11. You can bench-test a 1.8A PSU using the same procedure I described. I don't know what happens if you try this kind of PSU without a load, though.
  12. Re power supply testing: I tested my recently recapped Lisa PSUs on the bench by hooking up dummy loads (power resistors) to the +5, +12, and +33 volt rails. With these set up, you can check the voltages on all the rails to see if everything is in spec. Start by looking at the specs for the power supply in a copy of the Lisa Hardware Manual, like this one: http://lisa.sunder.net/LisaHardwareManual1983.pdf where PDF page 259 has the specs you need. Apply Ohm's Law to figure out resistor values to use to keep the current draw within the bounds specified for the three positive rails, and make sure that you use resistors that are capable of dissipating the dozen or two watts that you're going to pump through them. You can't run a 1.2A PSU without loads on these rails---the voltages will go far enough out of spec for the PSU's crowbar circuit to repeatedly "reboot" the power supply (making a clicking noise you can hear). We found that the -12v rail does not need a load in spite of the 0.01A minimum current spec, at least for a brief test. The PSU is nominally off when it's plugged in with nothing (or only the dummy loads) attached. In this state, though, the separate 5v standby supply is still active. You can test this voltage without a load, which is the thing to do first. Once you're ready to turn the PSU on, in addition to setting the dummy loads in place, you will need to connect the 5v rail to the 5v sense line (so that the PSU can monitor itself) and the 5v standby supply to the on/off line (so that the PSU turns itself on). Both of these connections must be maintained for as long as you want to keep the PSU running. It seems fine to arrange all the hookups with the unit unplugged and then to plug the thing in so that it turns itself on immediately. Some cryptic pinout information can be worked out from the schematic: http://bitsavers.informatik.uni-stuttgart.de/pdf/apple/lisa/hardware/050-4011-H_Power_Supply.pdf With the contacts on one side of the board labelled with numbers, and letters used for contacts on the other side (ambiguous letters like I and O are not used), you can work out what needs to be clipped where. It's a lucky break that there are no "hard" connections to clip for setting up the resistors and other connections---you can always clip right onto the edge connector, since it doesn't matter if the contacts on both sides at the places you'll need to clip are shorted. (In fact, this makes it easy to clip the +5v sense line to +5v.) This is not generally the case, but it is for the contacts you want to use. Once the PSU is set up and plugged in, test all of the power rails for the right voltages. I try to be quick about it, since it's not clear to me whether leaving the -12v rail unloaded would be OK for an extended period. Hope this helps!
  13. my first Lisa

    I don't think this makes a lot of sense. It's true that the Lisa doesn't have anything like the Toolkit in ROM. This said, I don't think ROM on the Lisa (or the Mac) is really much faster than RAM, so if the software designers had wanted to, they could have made the graphics routines memory-resident for access that was as fast as possible. In fact, I think MacWorks actually worked in essentially this way: it loaded a patched Mac ROM image into RAM, then used the Lisa's MMU to map that RAM region to the same memory addresses reserved for the ROM in a real Mac. So, effectively the same speed for access to graphics routines (and other toolkit stuff) as you would get with a ROM. The slower clock speed is more to blame, I think. Additionally, I don't think the Lisa software engineers were coding for speed and efficiency in the same way that the Mac engineers did. They had a whole megabyte to work with, after all!
  14. my first Lisa

    You know, that's actually an excellent question. Now that you mention it, I don't really remember why I had such an experience with the caps lock key---it was a few years ago that I did my pad replacement, and I can't remember why it was necessary to do anything besides dig the old pads out and clip the new ones in place. Why did I even need to mess with that mechanism in the first place? To try and refresh my memory, I did a little search and found this page with lots of pictures of the inside of the keyboard. There isn't a good picture of the caps lock key mechanism, but if you search for the string "bottom key switch profile", the image just above it shows the bottom of the keyswitches, with the caps lock key barely visible all the way to the right. Here is a direct link to the image itself... You can see a white plastic frame surrounding the bottom of the keyswitch, and if I remember correctly, this is a molded piece of plastic that holds the whole locking mechanism in place (and may even incorporate the shaped channel that the pin I mentioned slides around in). My advice is to treat this plastic piece with caution! Try not to let it move, because (if I remember correctly now) if it slips off, the spring and pin will be exposed. Please take this all with a grain of salt---it comes from some old memories, obviously---but one thing is for sure: when replacing your keyboard pads, treat the caps lock key with care!
  15. my first Lisa

    When you do open your keyboard, as you will have to do eventually (the pads will all degrade someday), please use extreme care when disassembling the caps lock key. The tiny spring and pin that are part of the key locking mechanism can easily fall out, and if they do, since they are extremely small, they can be very difficult to find on a work surface (or the floor!). In fact... during my own key pad replacement, I had the misfortune of having the spring in the caps lock mechanism shoot that little pin right into my eye! No harm done, luckily, and even more fortunately my wife and I managed to find the pin (which bounced off my eye) and spring rolling around on the floor. As dramatic as the whole procedure was for me, I wouldn't let this risk stop you from replacing your key pads---if you are aware of the issue and treat the caps lock key with care, you probably won't have a problem.
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