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Jinnai

6502
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    205
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  • Gender
    Male
  • Location
    Colorado Springs
  • Interests
    Vintage computers, woodoworking, anime

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  1. Jinnai

    unnamed (2)

    I like your car!
  2. Jinnai

    Suprise found in a Quadra 700

    Weird flex, but OK cards with boxes are awesome too.
  3. Jinnai

    Sony CR44 power supply repair... or not?

    I want to know if you find a solution. Your voltages aren't that far off: mine has between 1 and 2 volts on both 12v and 5v. I also recapped, but it didn't fix it.
  4. Jinnai

    John's Finds

    I used a yoyo adapter for mine. It just needs the larger connector tip. Sadly the vast majority of g3 adapters on eBay are the later, smaller type that also work with the g4 laptops. It's super awesome that it has the g3 upgrade!
  5. Jinnai

    John's Finds

    need me to recap it? Don't worry about a 9" screen if it's a terminal. My electronics engineering prowess is absolutely not high enough to make use of one - I just need one with a VGA connector to plug into an older Mac or Mini-ITX PC board.
  6. Jinnai

    John's Finds

    Well, I'm a little biased - I love CRTs in general. I think one with built-in speakers would be absolutely worth getting. Also, as I've said before, if you see a 9" SVGA CRT please consider getting it on my behalf. I have a ~1996 Performa that needs a monitor, and I'd prefer an Apple monitor, any model that's 16" or smaller should be fine. Sound like a nice haul. If the SE/30 has an xceed I'll die have you seen the internal hard drive bracket for the Mac Plus yet? By hard drives, do you mean external SCSI boxes, or internal?
  7. Jinnai

    John's Finds

    I can't help but be a little jealous of the IIx! Think any of the monitors were the smaller Macintosh ones? There is definitely a dearth of those here in Colorado ever since I misguidedly gave away the like 3 I had...
  8. Jinnai

    Rusty Macintosh SE/30

    So school has begun and I'm getting busier. I fixed what I could, and what I couldn't I swapped in from a spare SE I have. I was lucky that the motherboard worked. Other than that I had a spare CRT on hand that I added in and that was most of it. I have yet to fix some bugs on the analog board and CRT retrace circuit, but thats about it - the HDD and FDD are toast, and the PSU is likely toast without an oscilloscope to probe it further, I got as far as seeing that there was something wrong with the PWM circuitry. So those are swapped in from the SE. Got a new HDD and a nice big 2GB partition. Found some RAM on eBay for $16, bringing the total up to 20MB. Here it is running After Dark Star Trek: Pic of the inside with it's new HDD (which needed an adapter, but I must say it works very well) and it's snazzy pink sled: Next I will replace the case with a clear one from MacEffects once it comes out!
  9. Here is a list of the capacitors used in the M5651 Powerbook AC Adapter. C108 - 400v, 27uf, 16mm, 28mm, 7.5mm C111 - 50v, 47uf, 6mm, 11mm, 4.5mm C151 - 35v, 33uf, 6.5mm, 7mm, 4.5mm C201 - 16v, 1200uf, 10mm, 30mm, 5mm C202 - 16v, 180uf, 6.5mm, 15mm, 4.5mm C207 - 16v, 82uf, 5mm, 15mm, 4.5mm C252 - 50v, 1uf, 4mm, 6mm, 4.5mm
  10. Jinnai

    Macintosh SE blows transistor

    In an SE that I have, the same symptom was caused by a short on the CRT neck board, capacitor C5. It's worth testing with a multimeter. Does the PSU short if the analog board is plugged in, but not the motherboard? Could the short be electrolytic fluid on the motherboard?
  11. Jinnai

    Compact Mac Repair Guide

    There are at least three different power supplies - by Astec, Apple, and Sony. I have the doc for the Sony CR-44:
  12. Jinnai

    Rusty Macintosh SE/30

    Oh man, if only I had known when you shipped the PSU! But I thought for sure the issue would end up being in the ASC/capacitor area. An issue it is now having is rather bizarre - you kind of need a picture to see it: This SE/30: My working Classic II: Closeup of the dim "eroded" pixels in text: Some pixels are dim. I'm never heard of anything like it. I really want to get a new diode so I can verify that this is actually associated with the CRT board. At first I was just going to just leave it as it is, cause its far less distracting than the problem it had before, but it gets annoying if you actually try to use the computer for a while. It affects text and small images - the checkered background and screensavers look flawless - which made me wonder if the issue was somehow ROM related, but I don't think I had this issue with a known good CRT board. I'll need to get a diode to find out, or swap back in the diode I had taken from the good one.
  13. Jinnai

    Rusty Macintosh SE/30

    I worked on the power supply for a while, but couldn't find anything useful without an oscilloscope. Something is wrong in the area of the switching circuitry. So I'll put off that for now. I got a spare PSU from CC, though its not the Sony one, so it wouldn't help me understand the one I have any more than my schematic. I finally found the issue on the CRT board that was causing issues - CR2. The problems I were having were slight but numerous - occasional flickering, black smearing horizontally to varying degrees, and a slightly more noticable than usual retrace line. My meter stated that it was passing through about 1.4v instead of the usual 0.6v, so I replaced it and the issues went away. I think it may have been damaged by my killer CRT that took out Q1 and C5 as well. Now I have to ask, where might I find a replacement for CR2? I swapped in one from my SE CRT board, so I'm not sure what value to look for, or how one diode can differ from another. From what I understand, it's a question of what operating conditions it is rated for, and whether its a PN, zener, or other type of diode. This one reads, all on separate lines; R, IN, 41, 50. It looks like it's just gold with a black band. Yesterday I found why I was having boot issues - there was one bad stick of ram out of 8 1mb modules, difficult to catch because I'd only use 4 when testing. So I found it and swapped it out for a different one, and now all 8mb are working fine. The sound issue appears to be a bad speaker. I can take it apart and see what I think, but I don't know about repairing speakers. A quick ebay search didn't turn up any great results for 2.25" speakers either.
  14. Jinnai

    Macintosh SE/30 Sony PSU not working

    So if I try to measure the switching transistor output with the AC setting, I'll probably get nothing (or perhaps 0.9v?) whether it's working or not? That would be too bad. I went back as far as D252 on the 12v rail and D251 on the 5v - thats immediately after T151, in the hopes that I would find some measurable DC output, but I got the same as the analog board connector voltages. At least it's consistent, but yes I don't think switching power is coming to T151. It seems I can't verify that without a scope. Does the PWM circuit control the switching? If so maybe two things that could be wrong include the PWM components and the transistors themselves.
  15. Jinnai

    Macintosh SE/30 Sony PSU not working

    Just an update - I've been looking at the schematic and tested up to the main voltage from the biggest filtering cap and subsequent inductor, its about 164v, which seems good. Voltage on the yellow wire - +12v - starts at about 0.9 and slowly and steadily drops when measuring, it got to 0.22v before I got tired of holding the probes. I measured the output at transformer T154 - if I understand correctly and mind you I know I might be 100% wrong but I'm trying to understand whats going on - which is connected to the PWM chip, and got nothing at all. If I understand correctly, is it DC voltage at that stage? The switching PSU converts AC to DC, smooths it, and converts to high-frequency by switching via transistors Q151 and Q152, at which point it's switching, but still measurable with the DC setting on a multimeter, is that correct? There is a transformer later on in the circuit for the main 12v voltage - T151 I think - but if it cannot be used with the plain 164v output from the filter cap because a transformer won't do anything with flat DC current, it must be getting it's input from Q151 and Q152. How incorrect am I? Schematic for reference:
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