Jump to content

eraser

6502
  • Content Count

    233
  • Joined

  • Last visited

Profile Information

  • Gender
    Male
  • Location
    NC, USA

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. eraser

    Does anyone know how I might get this off?

    Thanks guys. I will experiment on a small section. I expect to retrobrite this Mac as it is because of needing to replace the faceplate too and the color doesn't exactly match. So I will get the case one uniform color one way or another.
  2. eraser

    Bad caps leading to slow performance ?

    The Performa 400 did indeed ship after 7.0 was released BUT "Performa" is only a name. All Performas are repackaged Macs in a "consumer friendly" way. That is, a Performa is a base model Mac (LC, Quadra, PowerMac, etc) that is given a Performa name and number and packaged with a collection of software and hardware meant to appeal to consumers. The actual logic board is identical. So, even though the Performa 400 shipped with 7.0, that Mac is electronically indistinguishable from an LC II and therefore can run any OS that the LC II can run ... because it's an LC II with a different name tag.
  3. It looks like paint. I hope that there is some way I can remove it without ruining the case plastic.
  4. eraser

    Bad caps leading to slow performance ?

    A Performa 475 is NOT an LC III. The Performa 475 is a 68LC040 and despite also running at 25 MHz, it will absolutely crush an LC III at everything. It's not even close. As Gorgonops pointed out, there is a 5x difference in performance from the 475 to the LCs. That isn't an exaggeration. The LC and LC II are the slowest color Macs. They were slow the day they were made and they are slow now. Appreciate them for what they are and don't expect too much from them.
  5. eraser

    No sound from Color Classic

    If you keep running this Mac without recapping it the damage will be permanent. There is zero doubt the caps have leaked and they are now no longer providing the proper capacitance. You are putting all of your ICs at risk by using it in this state. If the analog board/PSU hasn't been recapped it needs it too.
  6. eraser

    My First Recap - LC

    One more thing to consider: Identify the SERIES of capacitor in the original design because that matters too. I'll give you a real-life example. The power supply in the Quadra 630 uses quite a few United Chemi-Con SXE capacitors. If you look up the SXE series you will find that these caps are low impedance. When choosing your replacement cap you will want to also find one that meets all of the specs above (capacitance, voltage, temperature, size) but also is a low impedance design. You will also find caps in Macs that are low ESR (effective series resistance) and a few other features. Keep in mind that specialty caps like low impedance and/or low ESR are more expensive and if the engineers and bean counters decided that they were worth the cost then there is probably a good reason why they're there. If you can't identify the series of capacitor or if it seems generic then chances are it's just a "general purpose" cap. I'd also mention that you shouldn't use those specialty caps in place of general purpose ones because they can cause problems. The design of a particular circuit may depend on the resistance and/or impedance of the capacitor to function correctly. Suddenly eliminating that characteristic will change the behavior of the circuit in possibly undesirable ways. Yes. All the electrolytics must go. All other components can stay as long as they are not obviously burned or physically damaged. If you see a scorched component or PCB in a power supply that is a sure sign that something went very wrong at that spot.
  7. eraser

    C1 from "Classic Mac Repair Notes"

    Awesome, thanks guys!
  8. In "Classic Mac Repair Notes" it suggests replacing C1 with a special arrangement: Does anyone have a picture of what this looks like? It's hard for me to visualize.
  9. eraser

    PB3400 - Battery refuses to charge

    Are these rebuilt batteries? If not, there is no point in trying. The cells are long dead from age.
  10. eraser

    ImageWriter II Ribbons

    Pictures of new and old IW II ribbons
  11. eraser

    New ImageWriter II Color Ribbons

    Of course now I have new ribbons that are cheap enough to not have to fool with trying to make one yourself. (And personally considering the incredible mess and pain of trying to stuff many feet of ribbon back into a cartridge it never seemed worth it to me to even try that.) Which extension would that be? I can test it.
  12. eraser

    New ImageWriter II Color Ribbons

    Well said! MacPallete II does have a few configuration options. I hope to play with them a bit and see how much of a difference they make. and ... There are different versions of the ImageWriter II. The early revisions of the printer are very close in weight to the original ImageWriter and nearly 40 lbs. The last model, released in 1990, is dramatically lighter. The power supply accounted for quite a bit of the weight in the early ImageWriters. If you take one apart you will see why. There is one transformer in there that has to weigh a good 10 lbs all by itself. The weight difference between the 1980s and 1990s ImageWriter II is so much that I am certain that I could pick up one of them blindfolded and tell you exactly which model it was.
  13. eraser

    New ImageWriter II Color Ribbons

    I'm impressed with the ImageWriter II's color printing. I've been printing random color pictures on it just to see how they will look. Nobody would mistake its output with a modern photo printer but for a 30-year old dot matrix it does a good job. When using MacPalette II it prints the same page/image in 4 separate passes. Each pass adds a different primary color from the color ribbon. I find it really interesting to watch the image slowly appear on the paper as it mixes in each new set of colors. In terms of print speed though, it is incredibly slow. A full page color graphic or photo will take maybe 5-10 minutes to print including the time it takes for the machine to build the color maps.
  14. eraser

    New ImageWriter II Color Ribbons

    Update! I spoke with the factory folks and they say that there basically is no gear version of the 4C (four color) cartridge, and at this point I believe them. I have personally seen and know the following types exist: - Single color (black) short form factor w/ foam (1C-FOAM) - Single color (black) short form factor w/ gears (1C-GEAR) - Multicolor (4C) tall form factor w/ foam (4C-FOAM) I have never actually seen a 4C-GEAR but I figured that since 1C-GEAR exists that 4C-GEAR must. After all, the factory can make all of the types I just listed. I know that some people have managed to get ahold of working 4C cartridges. I assumed that those must have been the elusive 4C-GEAR but it’s entirely possible that these units were really 4C-FOAM that was produced late, produced from a particularly good stock or stored in ideal conditions. Apparently, though, there isn’t a 4C-GEAR. (If anyone can prove one exists, please let me know.) So, why no 4C-GEAR? I talked to the factory and found out that gear models are actually ideal for them to manufacture. The reason is that they mold all of the plastic parts in the factory but they can’t manufacture the foam. All of the foam they use has to be imported from another country and this increases the manufacturing difficulty and cost of the final ribbon cartridge. Companies that make make authorized ribbon cartridges (and other consumables) use a reference design from the printer manufacturer. In this case C.Itoh (not Apple) would be the likely originator of the original reference designs. The foam vs gear issue would have been just as relevant in the 80s and 90s. As a matter of fact it was probably even more of an issue then since they were being mass produced and any cost increase would impact profits all the way down the chain. I believe that with quite a bit of money on the line that if a 4C-GEAR was viable it would have been done. It appears as if there was some technical reason that 4C-GEAR is not an ideal design. I figure that if the manufacturers of the ImageWriter, who were actual printer engineers, decided not to use such a design that they must have a reason. Remember that the 4C is twice as tall and it’s possible that the additional height of the ribbon could cause problems with binding or possibly require more force to turn than C.Itoh engineers thought was ideal for the motor on the print head. These are just guesses. At any rate, trying to oversee the creation of a 4C-GEAR model would take quite a bit of time and money and it’s not clear if there is a real benefit at this point. It’s true that the foam used in the old stock of 4C-FOAM was a problem. We may have the same problem with these in a decade or two but there are probably bigger concerns by then. I just don’t know. In the meantime, we do now have brand new color ribbons for the ImageWriter and for the next few years we can look forward to bringing back full color dot matrix printing to the classic Mac. I should have the Trading Post ad up this weekend.
  15. eraser

    New ImageWriter II Color Ribbons

    I agree. I am trying to find out why they weren't able to deliver on the gear model. I'll keep you all posted. In the meantime, yes, fresh ribbons.
×