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macdoogie

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  1. I realize there are already SCSI to SD, CF etc out there, and all of these seem to have various issues with setup. I had once planned to make a version of my own, but not utilizing Compact Flash or SD Cards. I figured I'd just make a true Solid State SCSI drive with flash chips right on the board. I mean, do we really need 64 Gigabytes of storage for our vintage machines(I know, I know the old Macs can't even use all that )? I figured on making a SCSI-1 only, with a capacity of somewhere between 128MB and 1GB depending on the flash densities available(I'd likely use SPI based flash). I'd also
  2. Is your IBM drive an Apple OEM? I know Apple used IBM drives in the early-mid 1990s. Common sizes were 80MB, 160MB, and 320MB. Non of the "Apple Logo Sticker" drives should need an external terminator...
  3. Who would have thought that Orange would look so good on a monochrome Mac? Actually, many years ago I discovered that the Green CRT in the small Apple IIc monitor is the exact same size and fit as the original Mac. I retrofitted one of my Platinum Mac Plus machines with the green CRT which was pretty cool. I believe I had to swap the Yokes over as the IIc one had a different harness or something. It's quite possible that a collector buddy of mine still has that machine 20+ years later. Now I'm gonna ask :P
  4. macdoogie

    Walkmac

    Looks like the main difference between TTL video and the Mac's built in is mainly the polarity of the HSYNC and VIDEO signals. Perhaps that mystery signal is just tapping off of the raw video "shift register" circuit to avoid the need to add an additional inverter chip? Hmmm, I may have a copy of the MacPlus Logic board schematic somewhere in my archive.... Also, I agree with whoever above identified this as a plasma display. The Orange color gives it away. It also could be one of the earlier electroluminescent technologies. The contrast looks far too good to be an LCD of that vint
  5. It's true that Apple designs have used both Tantalum and Electrolytic. Although, in more recent years, they switched from Tantalums to "PosCaps" i'm guessing largely due to Tantalum being a conflict, or "blood" mineral. Still, on older boards, you'll see a mix. One obvious reason is cost. Tantalums are certainly more expensive than the old Aluminum electrolytic. However, the function of the capacitor it also a big factor. The basic uses for capacitors in a circuit are Bypass, Filtering, Decoupling, and Bulk. Some of these characteristics overlap of course and all are frequency dependent with a
  6. It's definitely not related to the capacitor voltage rating. Higher is always safer. Not necessarily always better, as the other characteristics change with the voltage rating like value derating(That 22uf is only 22uF at a certain range of temperature and voltages), and Equivalent Series Resistance. The latter is why I generally don't replace aluminum "cans" with tantalum caps. Tantalums have higher ESR and also when they blow it's pretty for a second, then not so pretty afterwards. Still people use them and they probably work fine under most if not all situations. I just like to use the form
  7. Are you sure that's an SVGA monitor? From the finder screen displayed above it looks like it's running 640x480 and not 800x600. When I modded a color classic to run at 800x600, it seemed clear that the dot pitch(stripe pitch actually on a Trinitron) wasn't quite fine enough to handle the 8x6 resolution. From my understanding the 9"(some call it 10"?) CRT was the same as Sony's famous studio monitors which were for older SDTV 480i resolutions(Actually 525 lines, but not all are visible).
  8. These newer industrial replacement displays actually use modern TFT technology like IPS, A-Si, and have LED backlights, so you can get ones that look pretty good. The Trinitron would win on contrast ratio, but at 640x480, the TFT would be sharper than a VGA modded Color Classic. Even at 512x384 the color classic can get fuzzy requiring a tradeoff between focus at the center of the screen or at the edges. Also, I'm still thinking about a replacement rear case to convert the CC into a slim, flat panel version with the MLB mounted vertically and the I/O ports facing down. The SCSI HDD would be re
  9. I noticed that the 8.4" screen chosen was one with an LVDS interface. The same company that makes that screen(Looks like Tianma may have purchased NEC's industrial TFT division?) has the same panels with a TTL interface, which is the more traditional RGB+HVC parallel interface. Those "everything-in-one" controller boards usually have both outputs present, but I'l like to make a more dedicated controller board that doesn't have a ton of unused connectors or need the OSD menu + buttons to work properly. Actually, I believe for the Color Classic, I can create a whole new analog board
  10. Any chance you could make a similar resin surface for the Color Classic's tube? I'm thinking of making a more dedicated controller board for the TFT if there is interest.
  11. Can't say that for certain, as I was just comparing the high level specs. However, in general, when the part number is exactly the same but with differing suffixes, the differences are usually just variants of the backlight and/or the polarizer stackup(to trade off contrast/viewing angle, etc) or even just "matte" vs glossy top film. Since this display appears to have the same interface and resolution, I would suspect that the LVDS interface is driven the same way for both. If I could dig up the data sheet for both, I could be a bit more certain.
  12. Ah, thanks for the clarification If you have a link to the driver board, I may be able to provide some insight. I have a lot of experience with TFT displays(about 5 years) from 1.5" OLEDs to 10.4" TFTs. I just don't have any direct experience with CCFL BLCs.
  13. Who are "They" that you refer to? From the looks of it the M is just a 200nit brightness panel compared to the 150nits of the S variant. If the BLC is also on the driver board, I would think that some component substitution could be done to accommodate whatever variance in voltage or current is needed for the brighter panel. Scratch that. I just realized that these are CCFL and not LED. There could be considerable differences in the Backlight Controller. I've actually never done a BLC for a CCFL panel myself. I know the voltages are much higher than for LED. I once singed my finger(made a sizz
  14. Note that from my reading of the QXGA Panel data sheet referenced in an earlier post, that display is what is called a "Dual-Link" LVDS. It needs 8-lanes to achieve that resolution. Regardless of the interface, TFT panels themselves will only accept data at their native resolution. Any scaling would have to be done by external circuitry on those adapter boards. Also note that while many of these "everything-in-one" adapter boards which accept VGA/Composite/S-video/DVI/HDMI may look the same as each other, there is still a bit of programming done on the board to adapt it to the target display.
  15. Wow, you guys have some brass bolt-fastening hardware! However you may be approaching this from the wrong "direction". A lot of things to address here, since I'm coming in late. 1. Getting the device/card "on the bus" with no contention is one thing, but that's no guarantee that the drivers will load. The PDS slot for the LC is hardwired to the 00EXXXXX/FEXXXXXX address space and designed for machines that intended to only have/fit a single device in that space. There's a good chance that the drivers are hard coded to expect the card to be at that address space. You can probably su
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