Christian, thanks for your warning. Since your post, I have been thinking that I should open up my 8250LP to see how the caps are doing. As the drive was repaired when I got it (replaced a faulty 6532) I have already replaced all caps on the main boards, but not in the drives. Today I had time to look at my 8250LP. I opened it up and noted that the drives were a bit different from Christian's pictures; my drives are JU-570's and the motor drive boards are of type PC-368 (Christian's are PC-368D). Pictures here: https://www.dropbox.com/sh/vj1cvc4q5ro7bk7/AABqK58yUqMJlun4LVeZyls3a?dl=0 The drive was easier to take apart as all I needed to remove was the drive from the case (not such a simple task in itself, must say!), and then take off the flywheel (three screws), lift it off (takes some force due the magnet in it) and then the PCB could be lifted out (four screws). No need to disassemble anything on the top of the drive and the spindle axis remains in place so no problems with alignment. Elkos in my drive are (uF/V): C01, C02: 22/10 C03: 4,7/25 C09, C05: 47/50 C10: 47/10 C12: 33/25 C13,C14,C15: 10/25 BP C17: 4,7/25 There was a little visible leak under the C01 and C02, and I replaced those right away. ESR-meter gave about 20 uF for both, with about 2,2 ohms ESR. Not too bad, and the drive was still working with them but clearly they had started to leak. I didn't have all of the required parts so I'll leave the final recap for a later time when I have ordered some more caps. The reverse side of the board was completely clean so no damage done there (yet). While there I also dumped the EPROM's now that I finally have a device to do that. Btw: is there a way to access the second drive with ZoomFloppy and cbmctrl? I can access the drive 0 as usual (cbmctrl dir 8). One way to go over the problem is to use WinVice 2.2 with access to the ZoomFloppy- attached drive, then use x64. Doing a "load"$",8" there gives the directory of drive 1 (interesting thing is that if there is no disk in drive 1, it then tries drive 0 and if there's disk, it returns it's directory). The file names with upper/lowercase letters show mixed but at least one can see if the drive responds as it should, ie. I was able to test both drives. -- Ville > Christian Dirks <Toast_r@IdeaLine.info> kirjoitti 25.2.2015 kello 1.32: > > You all know the Matsushita JU-570(-2) disk drives that are used in CBM > 8250lp, SFD-1001 and 8296-d. > Some of these JU-570 drives went through my hands in the last weeks. > All of them had damaged drive motor PCBs, caused by leaking electrolyte > capacitors. > I assume that all JU-570 drives are affected by this problem. > You may take a look at > http://forum.classic-computing.de/index.php?page=Thread&threadID=7382 > where I described the problem. In german, but the pictures should tell > anything. > > Christian > > -- > Christian Dirks > Toast_r@Idealine.info > > > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2015-03-14 20:00:05
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