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PowerBook 520c will not power up
Posted by: jeremywork on 2021-01-07 06:52:35 I was in my cellar now: I have 6 PowerBooks 5x0. They all have this missing pin as you call it. What do you read with a volt meter? I doubt yours would be inverted compared to mine...
Posted by: jeremywork on 2021-01-07 06:58:37 On your picture it looks like that there is no metal in the missing pin. All of mine show metal in it. Yeah, neither one of my adapters seem to have metal in that pin at all. I don't have a working battery to test charging with, but the PowerBooks indicate they briefly try to charge their worn out batteries before reporting fully charged.
Posted by: MikeatOSX on 2021-01-07 07:03:07 I don't measure it now. I have more important things to do now. I did it in the past to find out if there are more than one PB 5x0 power supplies with no power on vbatt+ BTW: I did not invent the expression "vbatt+". I found it on a picture of this power supply in Internet some years ago.
Posted by: jeremywork on 2021-01-07 07:10:35 They're labeled as such on the adapter brick itself; Vbatt and Vmain, so it makes sense. I suspect your label may be on the wrong pin though, since I see nothing on that pin and still find two separate +16v pins on mine.
Posted by: MikeatOSX on 2021-01-07 07:21:38 I measured them all in the past as I told you before. So believe it or not, I continue watching CNN now...
Posted by: MikeatOSX on 2021-01-07 07:53:33 I posted this picture 5 years ago here too: I found the original picture 12 years ago here: Your "missing female connector metal in position 4" is found 12 years ago also here:
Posted by: MikeatOSX on 2021-01-07 08:14:17 PowerBook 500 Series: Measuring AC Adapter Output: https://support.apple.com/kb/TA32851?locale=en_US&viewlocale=en_US
Posted by: EmmyOcelot on 2021-01-07 12:26:01 My power supply is on its way. From seeing the pictures and retesting my own, which gets no current on any hole, make me really hope and think it was that power supply. I wonder if there is a guide to make a modern replacement using the head for the plug, since its uncommon.... Guess I’ll continue looking :/
Posted by: Franklinstein on 2021-01-10 20:08:34 PowerBook power supplies are a pain. The 500 series is especially bad, both because it was a one-off power supply so it's difficult to get replacements, especially with the dual 16v power rails that it seems to supply, and also because the plastic is brittle and doesn't like to come apart without breaking. Inside it's packed tightly so it's not easy to replace the caps even if you do get it open. However ISTR something turned up on a Google search about someone splicing a generic 16v power supply into the 500's plug on VMAIN while ignoring the battery voltage supply. It worked but of course batteries no longer charged but that's not much of an issue if your batteries are dead or missing anyway.
Posted by: EmmyOcelot on 2021-01-11 00:45:36 If I could, I would just get blank plates and make that. I’m no master when it comes to building electronics from scratch so I’ll have to take real good care of that power supply until I can understand how the power supply works.
Posted by: EmmyOcelot on 2021-01-11 13:11:58 It’s ALIVE Both the ram and cpu are working just great with the new brick. And I can now confirm it was the old one. Guess it’s time to make a new one with the cable. Since I now have some extra parts, along with an entire lower assembly, I’ll test the parts and sell them here someone else can use them. Thanks everyone! This PowerBook just needs a SCSI2SD and it will be finished. 😉 Emmy
Posted by: jeremywork on 2021-01-11 13:15:19 Glad to see it worked out!
Posted by: EmmyOcelot on 2021-01-11 13:17:08 I was so worried I had spent money for nothing. Had that happen with some ram that turned out to be faulty. eBay returns are not always amazing.
Posted by: EmmyOcelot on 2021-01-11 16:05:42 If anyone wants the lower assembly, its up for sale in the trading post.
Posted by: jimjimx on 2021-01-18 01:16:33 Years ago, my 520 stopped working during the bootup... Really weird!! I ended up splicing the cable onto a IBM 16V 4.5A PSU, and everything worked fine. At a a later time, I cracked open the original PSU, and found a bunch of “magic smoke”.. I posted pictures on a different page somewhere here..
Posted by: jimjimx on 2021-01-18 01:34:37 I missed the edit window... Here’s the link with my smoked out PSU, and link to the PSU I changed it with. https://www.ebay.com/itm/GENUINE-IBM-02K6657-02K6669-16V-4-5A-ThinkPad-AC-Power-Adapter-Charger-OEM/252818420883?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140107095009%26meid%3Ddf53b130a53e4c909fc21325c44da5dd%26pid%3D100040%26rk%3D1%26rkt%3D4%26mehot%3Dlo%26sd%3D263471999128%26itm%3D252818420883&_trksid=p2046732.c100040.m2060
Posted by: EmmyOcelot on 2021-01-18 04:34:09 I have that spare so I may try this out @jimjimx. Thanks for the idea!
Posted by: EmmyOcelot on 2021-01-22 10:36:54 I’m continuing off of this one as it doesn’t seem to make sense creating another one on the same machine. Ok! I just got the cable for my PowerBook 520c and after plugging in the cable and trying a disk, no spinning noises or it being ejected. It will only come out if force eject it out. I’ll attach a video but I am sure the cable is in securely and correctly. What should I do? View attachment 63304234520__7D83EDA0-C510-4340-B03E-BD581FFA1871.MOV
Posted by: jeremywork on 2021-01-22 10:47:51 "Apple Personal Diagnostics" has a 'System Info' tab which shows detected floppy drives. I'd check to be sure it's detected by the system first. If it's not, I'd start inspecting the cable contacts. https://macintoshgarden.org/apps/apple-personal-diagnostics-111
Posted by: EmmyOcelot on 2021-01-22 12:24:18 How would you recommend getting this software onto my PowerBook? I have an Ethernet adapter but I have no idea how to configure it for something like a file server.
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