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  1. pb3623

    Need help with TAM cooling fan!

    Well, I did find out that, somehow, my DMM's 250 mA fuse had blown (it's opaque so I couldn't visually tell - I assume it's a ceramic - but there's no continuity). So I need to replace that. Should I be able to measure low current like this (less than 1A) using the 10A socket? As long as the range is properly set? Talked to the seller, he states it definitely was working without issue before he shipped so it must be something that failed spontaneously (and coincidentally) or failed due to internal damage in transit. I know voltage (potential) can exist without current (flow), but is there anything that would measure a 12V difference in potential without current? A bad ground? Does LaForge need to reverse polarity on the plasma coils?
  2. pb3623

    Need help with TAM cooling fan!

    Good morning! I will verify the condition of the DMM fuse when I get back to town. My DMM is nowhere near the quality of a Fluke. It does have 300mA/voltage and 10A sockets. I assume the 10A dial setting is for the range and not required for operating w/ the probe set to 10A. But I've been leaving it in the default/300mA socket since we're talking about 60-90 mA fans.
  3. pb3623

    Need help with TAM cooling fan!

    Haven't forgotten about this request. I'm happy to do that as soon as I get back in town from Spring Break holiday... probably Wednesday. Maybe it's my DMM, but putting it in series (3P to 5P, 5N to 4P, 4N to 3N) with the fan measured 0 amps, which I know is invalid and suggests the circuit is broken. Now, when I measure voltage IN SERIES (which I believe represents the sum of the voltage drops across each component), it's also 0. So, if I did everything right, this means the fan isn't working? But connect it to a 9V battery again and it spins up.
  4. pb3623

    G4 Cube DVDRW drive

    I've been boiling the belts in the two Cube drives I have, just to buy some time before they either break or stretch back out. Pictures would be appreciated. I bought what I thought was a Cube DVD-RW drive but the listing was wrong and it's a slot loader for a 2011 iMac. Would like to attempt a transplant since it's basically free to me (if I can use it, I won't claim the refund!)
  5. pb3623

    Need help with TAM cooling fan!

    So, I had so many fans out, just for size comparisons, yeah - my scale is off. I had a couple of 1.0 and 1.2-amp fans that were obviously on the big side (~120 mm) and I didn't use them for this test. But I did have a pair of 40 mm units - 12 V @ 60 and 90 mA (not 600/900) and I know they electrically work because I used a 9V battery to power them. I agree, using something like a 12V sealed lead acid battery would be apples to apples but didn't see 9V as being a bad short-term power source (at least to rule out fan failure - debris, etc). They're obviously low torque so I'd assume you could continue to drive one all the way down to maybe 4V or so. When I see "12V rail" I automatically assume the +12V supply coming from the PSU. In this case, it's a 2-pin fan header on the board that measures +12V, pin to probe. If I splice the wires and probe in series with the fan (thus sharing the 12V), the voltage drops to around +1V. Am I doing this wrong? Should I be measuring current in series instead of voltage? Or measure in parallel? Either way, what I intended to say (and this seems normal/WAI) is that the fan header appears to be capable of providing 12V, and I'm able to power the fans externally, so could it be something else? What you seen in the picture (since you're not familiar with the TAM) - it's basically a PM 6500 logic board turned 90 degrees counter-clockwise (ports on the right). the +12V fan header J17 is half-way down on the left, above the RAM. There is a 40 mm fan connected but not running. The stock fan has the red/blue leads. I ran two trace wires from the fan connector to test with the 9V battery (which worked).
  6. pb3623

    Need help with TAM cooling fan!

    Hey Byrd - Thanks for your note! The TAM absolutely boots - in fact, it runs fine (until it freezes), which led me to take off the fat back and see the bracket fan wasn't running. I brought up the 9V battery since I used it to test the fans themselves to make sure they weren't seized up w/ crud. I read somewhere once that the secondary fan (that's mounted behind the outlet on the back case) only comes on when needed but I can't find that reference anywhere. On my other TAM, the fan comes on immediately, which is what I assumed is normal behavior for a 2-pin fan... a 3- or 4-pin header would be needed to control the tach and report back to the BIOS. Maybe you hearing the second fan is why it sounds louder? The machine itself is in excellent shape - I really lucked out - cosmetically and electrically. It's been well taken care of. I won't profess to being an EE but I assume a properly sized fan will pull the difference between the ground (+0 V) and power (+12 V). So, if a fan load of 600mA reduces the voltage to +1 V, does that mean ground is bad (and is hot)? So @Byrd, can you measure across J17 without the fan and in series with the fan? @JDW You're a PSU and fan guru. Do you have any thoughts on this conundrum?
  7. Hello all, I got a second TAM last week off of one of the Facebook groups and, like the one I bought last fall, it also came well-appointed w/ a Sonnet G3/400. After some machine freezes, I took off the Fat Back and saw the frameless in the HD bracket was not on. I've since been working on certain tests, to the extent of my "trained monkey" abilities. Fan header J17 next to the ROM/cache slot measures 12.00 volts across both pins. The installed fan, using bridge wires, runs off of a 9V battery. I don't have the specs on this stock fan since the label isn't visible but I assume it's 12V, 600-900mA based on its size. I know the amperage needs to be known if a replacement was deemed necessary but the 9V battery should rule that out. I've tried a variety of other 12V fans of similar size, and they all work off a 9V battery and their original machines (one of which was a 603e CPU fan on a 6500) but none work on the TAM's fan header. The TAM doesn't appear to have another fan header for me to try. There is a 3-pin J7 behind the ADB ports (above the Cuda) that I'm not sure what it does but it measures 4-5V across two pins. I've reset the PRAM and CUDA just to say I did but again, J17 measures 12V. Seems the secondary fan (up in the upper right of the case, if you are looking at the rear) is connected to the backplane somehow. I can't get to it and it doesn't appear to run either. I've swapped out the Bose power supply/sub just in case it was a +12V supply issue. No other issues with the hardware that I'm aware of but I haven't gotten very far with it. I do know that Accelerator, Ethernet and HD both work without issue. Here is where it gets interesting. When I measure the voltage in series with one of the fans, the 12V drops to around 1 volt. When I take off the fan the supply goes back up to 12V. So, am be correct in stating that, under load, the voltage is dropping to where it isn't enough to move the fan? I wouldn't think there is a fan controller or any sort of fan logic since it's a 2-pin header (ground and power). But could something have shorted? If so, why do I still see 12V without load? Is there another way I can try to tap 12V from another location on the board? Am I even following the right methodology here? Thanks very much in advance!
  8. pb3623

    TAM black screen

    Dumb question but how long did you wait? I now have two TAMs that sometimes <shrug> will take up to a 45 seconds or so before the green power LED and display come on (right before Happy Mac). Both happen to have Sonnet G3 accelerators but I didn't try to replicate with them pulled.
  9. pb3623

    G4 Cube with Sonnet 1 GHz and other goodies

    Well, I did find v3.1 of the Sonnet Crescendo/Encore drivers for OS 9 and X... seems it's rock-solid in both now. Now I have the weirdest dual-boot problem where the X disk doesn't mount automatically in 9 and the 9 disk doesn't boot at all in X. I think I made the mistake of using Norton Disk Doctor instead of TechTool Pro. Side benefit - having Sonnet v3.1 over the 2.31 I found on the Garden made a world of difference for my TAM w/ its (previously) unstable G3 L2... thanks for the tip!
  10. pb3623

    G4 Cube with Sonnet 1 GHz and other goodies

    Thing is, I can't even boot from a 9.2 CD. Sometimes it will get to the desktop, and freeze shortly thereafter; other times it won't make it to the desktop. I have to go back and write this down but IIRC from last night, a 9.1 CD was stable. And, FWIW, Classic under 10.4 works fine.
  11. pb3623

    G4 Cube with Sonnet 1 GHz and other goodies

    Thanks. Me too. I'm still having issues booting into OS 9 (it freezes soon after Finder loads) so I don't know if it's a thermal issue that 10.4.11 doesn't have? But yea, I'm very happy to get my hands on a faster CPU.
  12. https://www.ebay.com/itm/UPGRADED-Apple-G4-Cube-1Ghz-Sonnet-Processor-1-5GB-RAM-500-GB-HD-Dual-Boot/273704226994?ssPageName=STRK%3AMEBIDX%3AIT&amp;_trksid=p2057872.m2749.l2649 Snagged this while I was putting the kids to bed one night last week... I wanted an accelerator for my existing Cube as well as a shot at a case that was in better condition. It arrived yesterday - two days early (thanks, FedEx). It has the 1 GHz Sonnet Encore/ST (I assume the Cube-specific "C" SKU?), 1.5 GB RAM (max, even though there are 2 x PC133 and 1 x PC100), a 16 MB ATI Rage6 (which I believe I'll be replacing with my 32 MB Radeon 7500), and two fans - one inline with the HD and one off the VRM. The HD is 500 GB and appears to have been partitioned w/ SpeedTools. The DVD-ROM was listed as "fully functional... tested" but it suffers from Stretched Belt Syndrome where it won't eject against the pull of Earth's gravity. I'm having some trouble with OS 9 on the second partition and it's loud - especially when the DVD spins up, there's a lot of vibration. I can't imagine needing 500 GB so I'll probably put drop in a 2.5" IDE to m.2 SSD as I've down with other machines.
  13. I thought there was an internal filter that sat between the 50-pin cable and the logic board AND the internal/single drive has to either have internal terminator or term at the end of the chain as usual? Or SCSI urban legends? I have a black terminator on my external AppleCD and an internal SCA drive that doesn’t appear to need it.
  14. Well, seeing as the ROM itself is electrically compatible between IIci, IIsi, IIfx, SE/30 and the Quadras, I think it’s safe to plug in without a fire, but then you have the matter of connecting to the stock oscillator. That’s the part that probably won’t work. And even for me in my Quadras, I never got it to chime, either the VSO or thr PowerPump.
  15. I thought maybe Newer Technology was the supplier but Spectrum was the manufacturer... for example, you might see a DATECS mobile printer made in Bulgaria that’s actually remarketed and sold under different names (depending on who holds the license in that country, like Infinite Peripherals in the US for the printer example) I’m telling you, that looks like my VSO (Q700/900). I’m on a plane ATM but I think I may have posted about it here, or perhaps I can pull my eBay purchase history. EDIT: Here it is: https://www.ebay.com/itm/Velocidad-variable-de-tecnologias-mas-recientes-Overdrive-Para-Quadra-700-900-/162396084032?_ul=BO&nma=true&si=2iYfWw2PcJoWgcPfrtBw%2B3eafDg%3D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557