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ian128K

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About ian128K

  • Birthday 02/29/1980

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    Seattle, WA

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  1. ian128K

    My first Apple IIc

    haha No, not the power brick; the base unit! You know, the thing with the logic board in it! It did seem like a fairly widespread thing at the time. I figure it was probably just that desktop computers were still new to the teachers, too, so they weren't all that savvy and probably one teacher called it that and then it spread throughout the school district. It wasn't until my Multimedia Tech class in high school that I learned what all the components inside of a typical desktop computer were. But for some reason I still have this urge to call the old Apple II desktops "CPUs" because of that old association they created in my brain. That makes total sense. Thanks! That's a great link! I'm not averse to making my own cables, but I'll probably just buy one pre-made in this case. That's a super cool tool, though! I can see myself getting quite a bit of use out of that. Now I just need to get a floppy to use it on!
  2. ian128K

    My first Apple IIc

    Got the insides cleaned out. Hadn't done the same with the monitor or the PSU before I decided to turn it on and do the PRINT PEEK(64447) command, which returned '0'. The monitor has a great picture, bright and crisp with no burn-in. I did notice when I first turned it on that there were these weird diagonal lines running through it. (Zoom in to see what I mean.) Oh no! Surely everything is terrible and I should just send the whole thing into the landfill. ... OR ... Yeah, just needed to turn the brightness down. Now the picture looks perfect! I'm going to be doing a full recap of everything, because as far as I know the caps in everything are all original. (I believe the seller's grandma was the original owner, and the seller mentioned that he never got around to recapping it.) I want to open up the PSU and the monitor anyway to see what state they're in inside, but I'm expecting those to be the same as the IIc itself—pretty clean. I doubt at this point that I'll be finding anything catastrophic. But, of course, the fact that 40-year-old electrolytic capacitors haven't exploded yet doesn't mean that they won't. Also, I don't have any 5 1/4" floppies anymore (other than my copies of Wolfenstein 3D and Ultima VI, which are PC-formatted) so I haven't tested the drive yet. I'll probably order one or two from rescuemyclassicmac.com. I've noticed that the PSU brick remains warm even when the unit is off. (I'm trying really hard not to call it the "CPU", which is what we were told to call it in school in the '80s; clearly the CPU is something rather more specific than the box with the logic board in it. But I digress!) So I've taken to unplugging it after I turn it off. Is it normal for it to be warm when plugged in but turned off?
  3. ian128K

    My first Apple IIc

    Thanks for the link! I just tested all the keys on the keyboard, and they feel quite clicky.
  4. ian128K

    My first Apple IIc

    So I started cleaning and taking apart the IIc. Some things to notice: Apparently someone had removed the serial sticker, so I have no clue what the serial number is for this machine. Is there any other place beside the box (which is also gone) that lists the serial number? Also interesting to note is that there seemed to be evidence of someone having opened the case before. Note the marks in the plastic in front of the clip: Anyway, opening it up, everything was pretty clean. A quick go with some compressed air and it looks like it's in pretty good condition. Probably has something to do with this little filter medium they attached to the top case over the vents: Is that standard? I don't recall ever seeing anything like that before. Upon removing the keyboard, I found... a twist tie. Weird. It looked like maybe something was leaking inside the power converter, so I decided to take a look. It's an ASTEC unit, btw: Opening it up, it doesn't look like any of the caps have popped. I just see that bit of schmutz that was visible from the outside. Easily cleaned up. It's getting late, so I'm going to call it a night.
  5. ian128K

    Newest conquest: Apple IIc

    Although, just now thinking, shouldn't the verb be "liberation"? And shouldn't that be the name of the "Conquests" forum? Aaaaaaaanyway, a couple days ago I spotted a Craigslist find that I wasn't able to resist, even though I'd initially had no plans to ever get one: an Apple IIc + monitor for $30! I ended up paying him $40, since he saved me a bit of money by reminding me of the price difference between walking onto the ferry and driving onto it. This guy seemed pretty savvy: he's even donated vintage computers to the Living Computer Museum here in Seattle. The IIc had been given to him by (I think he said) his grandma, and he was just not getting around to working on it, so he thought he'd make sure it got somewhere that it would be worked on. The only bummer is that he said that just a couple weeks before his grandma (might have been his mom, but I think it was grandma—doesn't really matter) gave him the machine, she'd thrown out the box and manuals and floppies that came with it. D'oh! I just brought it home yesterday. He said that he never turned it on while he had it, so the working condition is unknown. I'm going to open it up first and do some tests before powering it on, just to make sure nothing catastrophic has happened inside. I'll probably be posting over in the Apple II forum as I try to get this thing restored—it's been almost 30 years since I used an Apple II regularly, so I don't remember a whole lot. Plus I know almost nothing about it electrically. I did find the Apple IIc Technical Reference Manual from Apple on archive.org, though, and that has the schematics in it. Cosmetically, it's in fairly decent condition. Needs a good cleaning and definitely some retrobrite. There's a little bit of corrosion on the composite plug on the IIc end. Hopefully just a little bit of Deoxit will take care of that. If not, I have plenty of RCA jacks.
  6. ian128K

    Millenium bug after 20 years?

    http://www.synack.net/~bbraun/macapps.html
  7. ian128K

    PowerPC 7457 upgrade for iMac G4

    Err, K7D803671B-HC25. This thing.
  8. ian128K

    PowerPC 7457 upgrade for iMac G4

    This project is not dead! My workshop is now almost fully set up, though I do still need to decide what my BGA rework solution is going to be. I've been doing a tonne of research for this project, which resulted in some documents that some might find useful. First is a map of the pins/signals for the 745x chips, as well as the SRAM chips that the schematics specify should be used for the L3 cache. What's that you say? L3 cache in an iMac G4? Oh yes! Turns out the 820-1257 board is wired up for an L3 cache, but Apple just never populated it. It looks like there's just a small handful of resistors (4 pulldowns and two 0Ω resistors) that configure the machine to bypass the L3 cache. The schematics list all the components necessary for populating the L3 circuits (voltage regulator, pullup/pulldowns, filters, etc.) and where to put them. So unstuff the NOL3_CACHE resistors, and stuff the L3_CACHE components, and that should do it. (In theory.) It's worth trying, anyway. And even got a couple of the SRAM ICs (Samsung K7DB03671B-HC25) for about $30 a couple months ago on eBay. Anyway, the pinout/signal map is a Numbers file with the columns and rows laid out like the pins are in the datasheets. I wanted to make doubly sure that the 7450 and 7457 were actually pin-compatible, and to make sure that those pins match up with the signals in the schematic. So in each cell, it lists the name of the pin according to the datasheets for the 7450, 7455, and 7457, and the last line is the signal name on the PCB, according to the schematic. Cells with a red outline indicate pins that didn't match up 100%. (But from what I can tell, should be fine.) I find it a lot easier to read than the pinout/signal list in the datasheets. The second file is an Omnioutliner file for the PLL configurations, showing the bus multiplier in the leftmost column, with the other columns showing what the PLL config is for the 7450, 7457, and according to the iMac schematic, respectively. Made it a lot easier to see the differences in PLL configs between the 7450 and the 7457, showing that for the most part they line up. I'm uploading it here as a PDF because maybe not everyone has Omnioutliner. Also made a Soulver file to run some numbers, but I'm not going to upload that. It's just a little utility for me to figure out power consumption, using available data from the datasheets. (Imagine that! Data in a datasheet!) I was able to use it, though, to determine that I will need a beefier power supply, especially with the L3 cache. Basically, with everything configured the way I want, I'll be pulling ≈12.2 more watts than the original configuration. (I love when electrical work gets all mathy. ) So I found someone who was parting out their USB 2.0 iMac G4 and bought the power supply off of them for $20. 160W, which is 30 more than what the iMac currently has, which should cover the difference with more to spare. Of course, 30 more watts means more heat, so the exhaust fan is definitely going to need to be beefier. I'm still looking into that. Also, the 160W PSU has a 16-pin molex connector, rather than the 14-pin on my iMac. Not an deal-breaker, though; all the signals are the same, with the addition of an extra pin going to ground and an extra pin going to FireWire power directly, which is an interesting quirk of the USB 2.0 iMac. But if you took those pins off, then the pinout is the same as the 14-pin molex. So that should be pretty easy to adapt. All that said, I decided that I'm going to work on the compacts first before I get to the iMac. They definitely need more love at the moment to get to full working order. BGA IC Pinouts.numbers PLL Configurations.pdf
  9. ian128K

    Bolles finds

    Nice haul! For the RAM slots on the IIfx, try spraying some Deoxit D5 on them. Same with those corroded pads/joints/etc. in that photo. I'd say probably also worth it to reflow all the joints in the affected area, though I'd do that after the Deoxit.
  10. ian128K

    Building the fastest Power Mac 9600

    And that's even with the original SRAMs installed? You mentioned back in June that you "soldered the original 700MHz 7451 back on and cache is working just fine with that one." Is it still enabling with the 7451, but fails with the 7455?
  11. ian128K

    Building the fastest Power Mac 9600

    Aren't you supposed to install the Sonnet CPU extension for OS 9 in order to enable cache on those upgrade cards? And SonnetCache for OS X?
  12. ian128K

    ISO Repair Service for Compact Mac

    SE/30 definitely sounds like it needs to get cleaned up and recapped. The sooner the better on that one. As for the CC, if all that's happening is the brightness is too high, that sounds to me like an adjustment issue. That part you should be able to do on your own. Just google for the service manual and you should find what you need.
  13. ian128K

    Question on graphics on Color Classic

    A recap can't hurt, for sure, but I second JIT's display adjustment comment. First thing I noticed in the photo is that the raster is misaligned (it's hugging the left of the display) and the image does appear to bow on the sides. I think Cory's right in that the raster was adjusted to be too big. Definitely check out the service manual for how to adjust the display and do it by the book. CRT technology was famous for not being able to display as clear of an image on the very edges of the tube, which is why there's often that margin of black space around the raster. If a recap and readjustment doesn't help, and even using the tube in another known-good CC doesn't help, then yeah, the tube might be getting "tired". A CRT rejuvenator can help in that case—but it's only something you'll want to do as a last resort, and rarely, as it can reduce the overall life of the display and the rejuvenation or reactivation won't last forever. Edit: Also, I should say that, judging by the photo, it doesn't look like your CRT needs rejuvenation or reactivation. The colours and brightness look fine on it, overall.
  14. ian128K

    PowerPC 7457 upgrade for iMac G4

    Nice! I've already got v2.1.0 and v3.0.1. The Readme for 3.0.1 does say that it also works on the 7457:
  15. ian128K

    PowerPC 7457 upgrade for iMac G4

    Going through the schematics, I've identified every MOSFET on the 820-1257 board that's not in an IC. BOOTBANGER (Page 21) - Q36, Q37: 2N7002 Voltage Regulators (Page 22) - Q16: 2N7002 - Q30, Q33, Q35: IRF7822 - Q38: IRF7822 (NOSTUFF) DC/DC CONVERTER 5V AND 3.3V POWER CONNECTOR (Page 27) - Q11, Q12, Q14, Q20: 2N7002 - Q19, Q29, Q31, Q32, Q34: IRF7805 PMU SERIAL DL, LPWR CTRL, TMDS POWER (Page 28) - Q7, Q9, Q13, Q23: Si3443DV - Q6, Q8, Q10, Q15, Q25, Q27, Q28: 2N7002 TUMBLER AUDIO, HEADPHONE DRIVER (Page 30) - Q5: 2N7002 TUMBLER AUDIO, POWER AMP. (Page 32) - Q22, Q24, Q26: 2N7002 I think only the MOSFETs on Page 22 would be affected by the voltage change to VGER_VCORE, as none of the outputs from the CPU go to any components with MOSFETs. Something interesting related to VGER_VCORE that I still need to figure out: on Page 33, that signal is listed as being 2V, but on Page 22 it says pretty plainly that VGER_VCORE is set for 1.65V. (Which would make sense, as that's the core voltage of the 7450/7451.) All the other signals on that page that have their set-for voltages declared match with Page 33, so I need to figure out why there's a discrepancy for VGER_VCORE. Also, the voltage regulator on Page 22 is identified as an LTC1735CS, not an LTC1628 like I originally thought. (Though there is a LTC1628 at U31 on Page 27.) Some or all of the MOSFETs on Page 22 may need heatsinks, which can be calculated. I just need to figure out what their Vgs is going to be with the resistor change on R262 so that I can then find what the Rds will be according to the datasheet, but I'm having a hard time following the voltage through the LTC1735CS on the schematic. I think I may have to make a test model of the circuit once I get home in September, but I'll keep trying to work this out on paper in the meantime. Maybe some Thevenising might help.
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