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warmech

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  1. warmech

    M1296 12" RGB Monitor - No High Voltage?

    Doesn't look like I can edit my previous post, but, that may be either grey or violet for the first band; after looking at mine again under very bright white light, it is difficult to tell if it is either grey or violet. Would there be that big a difference between .72 Ohms and .82 Ohms? I know it's B+ traveling across them, but, can .1 Ohms even have that big an impact on it? Either way, I've confirmed both of mine are trash after using a second multimeter, so any confirmation will have to be external to these.
  2. warmech

    M1296 12" RGB Monitor - No High Voltage?

    Okay, after some more googling, these look like 820 mOhm 5% 2W resistors - Grey | Red | Silver | Gold. I'm basing this off of my photos, the recent one above, and (amazingly) an M1296 diagnostic video that I was surprised to find was made by you (screenshot below)! I'm guessing the color bands did actually burn off over time, just like you said - also, I doubt that band between red and gold is white, lest we be dealing with an 8.2 GOhm resistor, lol. Think that's a reasonable theory?
  3. warmech

    M1296 12" RGB Monitor - No High Voltage?

    Hehe, sorry to jump the gun on you, there. Both resistors appear to be toast, unfortunately, as a multimeter reading fails on both. I've been searching for photos of the chassis to no avail as well, sadly. Any help is tremendously appreciated, and thank you again for your assistance! Edit: Speak of the devil! I found a nice, large image, but there's just a little too much glare to tell what the third color is, but it looks different on each resistor.
  4. warmech

    M1296 12" RGB Monitor - No High Voltage?

    Sweet deal! So those are 5.5K ohm resistors, then?
  5. warmech

    M1296 12" RGB Monitor - No High Voltage?

    So I pulled the chassis and, as suspected, the area under C418 is pretty rough. The good news is that everything except for one trace (between the two resistors next to C418) tests okay; some of them are pretty roughshod, though, so I'm going to jumper anything that looks eaten just to be safe. The two resistors are another story altogether, though. In flipping the board back over, I grazed one of the resistors next to C418 and it just instantly fell apart. I'm going to assume the other is in a similar state, lol. I can't find schematics for this chassis, testing reveals they're toast, and the colors are a little faded on the them, but are those 5.5K ohm (Green Green Red Silver) resistors? Altogether, this looks addressable if there's nothing else amiss. Would it be worth pulling the transistor nearby (D1138) and testing it, or is it unlikely to have suffered aside from trace destruction? Either way, I'm going to order new caps and resistors (once I know the value for certain) and see where that takes me. Everything else on the board looks okay - the flyback isn't cracked or leaking and nothing else looks eaten up or blown out.
  6. warmech

    M1296 12" RGB Monitor - No High Voltage?

    I was hoping that wouldn't be the scenario, lol. Thank you so very much for pointing me toward that; I'm going to start looking for damage. I'm assuming the horizontal transistor will need a replacement as well?
  7. So I got my hands on a 12" RGB monitor, but it does not appear to have much life to it. The font LED comes on, but there seem to be no other signs of life: no degausser hum (though that can vary from monitor to monitor) and no neck glow. C418 looks like it's leaked some fluid but, from what I've read so far, that doesn't especially seem like it would cause the monitor to go into shutdown; the usual issues with that cap appear to be related to image geometry more than anything, but I'm open to it being a culprit. The fuse is good and no other components look to have blown; there are no bulging caps but, having worked on (much simpler) 15KHz arcade monitors, that isn't always an authoritatively good sign. Before I go testing yanking the chassis out and testing transistors, is there any advice anyone can toss my way? If a cap kit is a likely fix, then I'm more than willing to take care of it; I'm just worried a transistor (or the flyback) has gone that is now unobtanium and would render much of the work in trying to figure out what's happening pointless. Thanks y'all!
  8. Okay, so after some additional examination it is safe to say that the +5v rail is, indeed, shorted to ground somewhere. I got suspicious after testing for bad caps and, sure enough, the +5v pins on the logic board's PSU connector all show continuity with the GND pins. I've removed (and reinstalled) the power connector and found no issues underneath it, so it's not a problem there. The PSU is fine and outputs the correct voltages, so it's definitely local to the logic board... I just have no idea where. As massive as this thing is, I don't even know where to begin looking for a short. Are there even schematics available for the 950? Even so, with that kind of a short, is this thing even salvageable?
  9. Hey! We're back to square one, but at least it isn't as dead as I had assumed. Voltages look fine so far all over the place, but I'm still testing. This thing doesn't need drives hooked up to boot to the screen, does it? I know that's probably a dumb question, but this is an enormous, clunky, and (for me) somewhat rare piece of hardware, and I feel a bit out of my element just looking at it, lol.
  10. Well, went and checked - C155 is shorted, along with just about every other capacitor. The +5v rail is shorted to ground somewhere; I'm guessing that probably fried a few things. Oh well, it will make a nice shelf piece.
  11. Plastic, which is what made the smoke/burning smell; there wasn't any visible metal anywhere nearby, which is what threw me for a loop. I just got back from running errands, so I'm going to eat dinner and have another look in a few.
  12. Same result, unfortunately; not sure why I had it disconnected in this image. However, I fear it may be dead dead now. I powered it up, noticed a burning smell, and then the PSU cut off a moment later. I looked under the board and noticed a couple of burnt pins on the bottom first socket for bank A of RAM. I'm assuming it's completely toast at this point, yeah? EDIT: for what it's worth, I didn't exactly expect this thing to work perfectly when I got it. I am a bit disappointed that this wound up happening, though.
  13. Regarding the VRAM/ROMS: good to know - thanks! I've tried four sticks of matching RAM in every bank to no avail; I have a green light on the logic board, but still no chime or video. The PRAM battery is new - pulled from a working machine, so I know it's a good one - but it's also had no effect. For what it's worth, there is nothing attached to the board at the moment; it's just a bare board with a keyboard and monitor running to it.
  14. Howdy, everyone! I just got ahold of a Q950 with a dusty, but other wise good looking, logic board that will not boot. The PSU appears to be putting out the correct voltages when powered on, so I think I can rule that out. Any display I hook up to it registers that a signal is being sent, but there's just no video. The speaker clicks loudly on power-up, but no chimes are produced. I've removed all the RAM and tried it with just what's onboard, but still no change in behavior. These beasts are entirely new to me, so I'm a bit lost where to go next; any advice would be greatly appreciated. Also, there appear to be four DIMMs that I am assuming are the ROMs. They have no identification, so I have no idea if they are even in the correct slots. Is there a way to determine if they are? Alternatively, are they even ROMs? Thanks much, Will
  15. warmech

    LC Boot Issues

    Got the DFAC replaced with one from a very much dead Classic II (RIP, old friend) and audio is back! The LC lives again.
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