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In need of Quadra 700 schematic - RIP: Quadra 700 1991-2015
Posted by: lopaka1998 on 2015-02-26 19:30:08 Does anyone have a quadra 700 schematic? I want to try to resurrect it. Well my quadra 700 died yesterday. One of those damn Maxwell batteries peed all over the board. Well... I noticed it yesterday. It ate away a few oscillators/clocks. I've removed a lot of the acid using acetone. I'm surprised that for the most part most of the traces seem to be intact. I've also lost a few diodes, caps, and resistors. Considering how far it went, I'm surprised the damage isn't worse. I'm mostly concerned about the corrosion at the via's at the moment. It ate the connection points to the first two ram chips. It looks like all of the custom chips are probably intact - some have corrosion on one side of legs, but not the other. So it's possible it may be recoverable. The acid went across the board in about a 1 and a half inch line across the board right up to the video output connector.
Posted by: trag on 2015-02-27 10:12:27 No schematic, but I wish you good luck and offer my sympathy on the battery leak. That is not pretty.
Posted by: lopaka1998 on 2015-02-27 18:27:04 No schematic, but I wish you good luck and offer my sympathy on the battery leak. That is not pretty. Thanks trag. If anyone could take a good quality photo of the top of a quadra 700 circuit board - I would really appreciate it. It'll help me identify missing parts, and get appropriate replacements. Just something good enough to read the part numbers on the chips, etc will do nicely. Does anyone out there have any spare parts or dead boards? Does anybody offhand know if the power supplies for the quadra700 and the iici are compatible? I've got a intact iici, and it would be nice to test the quadra supply in the iici first... as long as it's pinout is identical. As soon as I've got most of the obvious acid off, I'll have a parts list , like right now I need D6, which is hte diode going to the battery I think.
Posted by: TheWhiteFalcon on 2015-02-27 18:33:49 I'll get you the pics, you can check my conquest thread to see if there's any good ones there now.
Posted by: TheWhiteFalcon on 2015-02-28 07:38:05 Get ready for pic dump.
Posted by: TheWhiteFalcon on 2015-02-28 07:39:47 There may be a few repeats. Let me know if you need some closer shots of a particular area. Also, there may be one or two differences, mine is a prototype board but as far as I've been able to tell it's the same as the production boards save for some color differences. EDIT: Actually, it may be more unique than I thought, but the values should be the same...probably. :-/
Posted by: trag on 2015-03-02 11:33:41 Regarding power supplies, the following are pretty much drop in replaceable for each other, although, I think there were some (later?) models which had somewhat higher capacity (wattage). IIcx, IIci, IIvi, IIvx, Q700, Centris 650, Q650, PM7100. Also, on a bench, outside of the computer case one can use a IIsi power supply to test any of the above logic boards.
Posted by: lopaka1998 on 2015-03-02 22:19:28 Thanks White Falcon and trag for your help. Those pictures are a real help. I've found a few silkscreened parts that are only silkscreened - were never put in, and other parts that I'm missing that presumably disintegrated. It's helping me build my needed parts list. It's also good to know I can check the quadra 700 with a similar model power supply. An update: Well I've cleaned up the board quite a bit. I've also removed the first simm bank located at J23. This is the only point on the board that the acid went through the solder joints enough to corrode the other side. It makes sense - it was right next to the battery. I've cleaned the via's somewhat. Some are iffy, so this bank may be lost permanently. Hopefully I can replace it with a new simm socket and everything will work. On a good note... just for fun, I sandpapered clean the leads on the power on led, and wired 3v to it temporarily... The nice green led turned on... despite the corrosion on the leads... there is hope!
Posted by: unity on 2015-03-02 22:53:34 Vinegar. Soak for no more than 30 minutes. It seems to work fairly well for clean-up. I used store bough white vinegar and apply it gently with a tooth brush. I puddle it on and let it soak. I apply as needed to keep it wet during soak time. Then a gentle scrub followed by a water bath.
Posted by: lopaka1998 on 2015-03-14 18:02:32 I've been doing exactly that and it seems to be getting a lot of junk off. Thanks for the suggestion! Vinegar. Soak for no more than 30 minutes. It seems to work fairly well for clean-up. I used store bough white vinegar and apply it gently with a tooth brush. I puddle it on and let it soak. I apply as needed to keep it wet during soak time. Then a gentle scrub followed by a water bath. I have a parts need list. If anyone could help me identify the specs on these parts it would be helpful. For example, all resistors have a value like 101 or somethign on them... that'll help me identify replacements. Here's what I need: parts list d6 c65 d5 y6 - maybe - have part - may be functional. c52 r57 y3 r18 c72 u20 - maybe - have part - 53c96 - may be functional g1 - maybe - have part - may be functional If you can tell me what's written of them - or their specs if you know. For the caps, I can desolder a cap nearby and measure it to get it's uf or pf rating. For the rest of it - especially the oscillators y3 and G1, I need the numbers on the chip. I'm pretty sure they're all square wave oscillators, but knowing the frequency on the y3 one would help, along with part number, etc... Thanks to anyone that has info on the resistors, diodes, and oscillators listed above. The next step is removing chips with corroded pads, cleaning it up, and re-soldering onto the pads. After that and replacing missing components, and any cleaning I deem necessary, I'll do a test start and see what happens.
Posted by: joethezombie on 2015-09-25 13:58:15 I'm working on a dead 700 as well. Hopefully we can revive them! If you're still working on that mess of a board, here's some help! D5 is the same component as D6. Looks like a SOT-23 diode marked with 5D x C65 is marked A5, perhaps a .1uF ceramic capacitor, but who knows with the mess that is capacitor markings... Y6 is marked with two lines 32.768K 5181A - 32.768K crystal C52 is marked A4, perhaps a .01uF ceramic capacitor R57 is marked 220, 22Ω resistor. Y3 is marked 0103T1J, crystal of unknownness R18 is marked 220, 22Ω resistor. C72 is marked 10-16 B9, perhaps a 10uF 16V capacitor U20 is marked NCR 53C96 CP00419 609-3400514 9139R, ultra-SCSI controller G1 is marked K1149CAR 8186 197-0529 100.000 MHZ 9144, oscillator
Posted by: uniserver on 2015-09-25 14:30:33 talk to ted hodges he will sell you a whole Q700 for like 50 bucks.
Posted by: MJ313 on 2015-09-25 16:55:26 He might even ship just a mobo which would be easier and less costly.
Posted by: joethezombie on 2015-09-26 18:09:05 But it's interesting to try and repair it.
Posted by: MJ313 on 2015-09-26 18:38:41 Absolutely! I am rooting for you to get her up and running. But a plan B is out there, which you may not have known about; I think Uni was trying to be helpful.
Posted by: 360alaska on 2015-09-26 19:40:17 I have a spare q700 motherboard in a anti static bag in a box, it works perfectly, I just pulled it because I got a q800 motherboard to put in my q700. Pm me for details...
Posted by: joethezombie on 2015-09-26 20:00:52 Absolutely! I am rooting for you to get her up and running. But a plan B is out there, which you may not have known about; I think Uni was trying to be helpful. Oh don't get me wrong; Uni was indeed very helpful (as always!), and I have contacted Ted, although for a different matter. I do have another Q700 that should (crosses fingers) be working when my SCSI2SD arrives. The bad board I'm tinkering with has kind of turned to a personal challenge! Even cracked out the old 2445A which hasn't been powered up for over a decade!
Posted by: joethezombie on 2015-09-28 11:58:29 Mine came that way from the seller, so I've learned the lesson without any loss. I knew it wasn't working when I got it, he threw it in for $5 on the side of another deal. But I hear you. Pull those batteries, gents! On a side note, I got mine to stop clicking and actually access the disk on startup, but it freezes in the boot.
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