From: Eric Chomko Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Osborne I -update #4 Date: 13 Mar 2000 15:15:44 GMT Organization: IDT Internet Services Lines: 43 Message-ID: <8aj0n0$hl0@nnrp4.farm.idt.net> NNTP-Posting-Host: u2.farm.idt.net X-Newsreader: TIN [UNIX 1.3 unoff BETA release 961025] Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!feed2.news.luth.se!luth.se!cam-news-hub1.bbnplanet.com!news.gtei.net!newsfeed.mathworks.com!news.idt.net!nntp.farm.idt.net!u2.farm.idt.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:51780 So far I have tried the following with no luck booting the system: ----------------------------------------------------------------------- 1) leaning the connectors and reseating the boards. 2) sing a Q-tip to clean the R/W heads w/isopropyl alcohol 3) resetting the disk rotation speed by tweaking the pot on the board 4) very small amount of light weight oil near stepper motor mechanical piston (radial arm) A few notes about the behavior (unchanged) by doing the above: ------------------------------------------------------------------------ 1) I have used no chemicals on the connectors other than Q-tip on R/W head 2) I managed to get the rotaion marks, under a light, to move forward and then backward, I stopped when they appeared to stand perfectly still 3) on the A drive I get "Bdos error: sector read error", and then the drive stops and the red LED turns off, when I hit return (boot) the light come on I get another error message and the disk spins for awhile and then shuts off again, I can repeat this over and over again 4) on the B drive (double quote char " used to boot); the drive turns on and spins and continues to spin until I hit reset, no error messsage and no auto shutoff like A drive. 5) I have NOT tried to remove the double density circuit board, but I am considering it as the nesxt step as a poster indicated that the O-1 w/DD capability had some flakiness w/DD operation of drives. 6) The stepper motor seems to engage on drive A and move a little, on drive B it did nothing and then I reseated the connector to it and it now moves a little Any additional suggestions appreciated. I sure as heck would like to get at least one drive working. Thanks, Eric ###### From: Charles Eicher Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 13 Mar 2000 10:19:33 -0800 Lines: 62 Message-ID: <8ajbfl$2m4k@edrn.newsguy.com> References: <8aj0n0$hl0@nnrp4.farm.idt.net> NNTP-Posting-Host: p-328.newsdawg.com Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!isdnet!logbridge.uoregon.edu!newsfeed.direct.ca!pln-w!spln!extra.newsguy.com!newsp.newsguy.com!edrn Xref: chonsp.franklin.ch alt.folklore.computers:51794 In article <8aj0n0$hl0@nnrp4.farm.idt.net>, Eric says... > >So far I have tried the following with no luck booting the system: >----------------------------------------------------------------------- >1) leaning the connectors and reseating the boards. > >2) sing a Q-tip to clean the R/W heads w/isopropyl alcohol > >3) resetting the disk rotation speed by tweaking the pot on the board > >4) very small amount of light weight oil near stepper motor mechanical >piston (radial arm) > > > >A few notes about the behavior (unchanged) by doing the above: >------------------------------------------------------------------------ >1) I have used no chemicals on the connectors other than Q-tip on R/W head Try inspecting the heads, maybe you could get a small dental mirror or something like that inside without doing any damage. I recall that occasionally small pieces of magnetic media would chip off and get welded to the RW head. You might do better with an old-style cleaning disk. >2) I managed to get the rotaion marks, under a light, to move forward and >then backward, I stopped when they appeared to stand perfectly still There should be 2 sets of alignment marks, one for 50hz lights and one for 60hz. The Siemens drives were commonly used in Europe, where the fluorescents flash at 50hz. If you align to the wrong set, you'll be way off. Alas, I don't recall which set is the correct one for the US. >3) on the A drive I get "Bdos error: sector read error", and then the >drive stops and the red LED turns off, when I hit return (boot) the light >come on I get another error message and the disk spins for awhile and then >shuts off again, I can repeat this over and over again > >4) on the B drive (double quote char " used to boot); the drive turns on >and spins and continues to spin until I hit reset, no error messsage and >no auto shutoff like A drive. > >5) I have NOT tried to remove the double density circuit board, but I am >considering it as the nesxt step as a poster indicated that the O-1 w/DD >capability had some flakiness w/DD operation of drives. It may be stating the obvious, but you'll need a different set of boot disks if you change the drives to SD. >6) The stepper motor seems to engage on drive A and move a little, on >drive B it did nothing and then I reseated the connector to it and it now >moves a little Sounds like the stepper motors are nearly dead. I hate to be pessimistic, but I don't think these drives are recoverable. >Any additional suggestions appreciated. I sure as heck would like to get >at least one drive working. > >Thanks, > >Eric ###### Path: chonsp.franklin.ch!not-for-mail From: Neil Franklin Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 14 Mar 2000 21:14:59 +0100 Organization: My own Private Self Lines: 27 Message-ID: <6u8zzl71h8.fsf@chonsp.franklin.ch> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <8ajbfl$2m4k@edrn.newsguy.com> NNTP-Posting-Host: chonsp.franklin.ch X-Trace: chonsp.franklin.ch 953064904 377 10.0.3.2 (14 Mar 2000 20:15:04 GMT) X-Complaints-To: news@chonsp.franklin.ch NNTP-Posting-Date: 14 Mar 2000 20:15:04 GMT X-Newsreader: Gnus v5.7/Emacs 20.4 Xref: chonsp.franklin.ch alt.folklore.computers:51949 Charles Eicher writes: > In article <8aj0n0$hl0@nnrp4.farm.idt.net>, Eric says... > > > >2) I managed to get the rotaion marks, under a light, to move forward and > >then backward, I stopped when they appeared to stand perfectly still > > There should be 2 sets of alignment marks, one for 50hz lights and one for 60hz. > The Siemens drives were commonly used in Europe, where the fluorescents flashat > 50hz. If you align to the wrong set, you'll be way off. Alas, I don't recall > which set is the correct one for the US. Assuming these to be standard 300rpm (5r/s) drives: On 50Hz you have 10 flashes per rotation, on 60Hz 12 flashes per rotation. So the ring of allignment marks which are nearer together is the 60Hz one for the U.S. If there is only one ring of marks, count them and check for them being 12. -- Neil Franklin, neil@franklin.ch.remove http://neil.franklin.ch/ Nerd, Geek, Hacker, Unix Guru, Sysadmin, Roleplayer, Mystic Use a WIMP (Windows Icons Mouse Pulldowns) interface - or get one with a CLUE (Command Linue User Environment)? ###### From: Eric Chomko Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 15 Mar 2000 16:37:30 GMT Organization: IDT Internet Services Lines: 36 Message-ID: <8aoe8a$mgn@nnrp4.farm.idt.net> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <8ajbfl$2m4k@edrn.newsguy.com> <6u8zzl71h8.fsf@chonsp.franklin.ch> NNTP-Posting-Host: u2.farm.idt.net X-Newsreader: TIN [UNIX 1.3 unoff BETA release 961025] Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!newsfeed.mathworks.com!news.idt.net!nntp.farm.idt.net!u2.farm.idt.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:51986 In alt.folklore.computers Neil Franklin wrote: : Charles Eicher writes: : > In article <8aj0n0$hl0@nnrp4.farm.idt.net>, Eric says... : > > : > >2) I managed to get the rotaion marks, under a light, to move forward and : > >then backward, I stopped when they appeared to stand perfectly still : > : > There should be 2 sets of alignment marks, one for 50hz lights and one for 60hz. : > The Siemens drives were commonly used in Europe, where the fluorescents flashat : > 50hz. If you align to the wrong set, you'll be way off. Alas, I don't recall : > which set is the correct one for the US. : Assuming these to be standard 300rpm (5r/s) drives: : On 50Hz you have 10 flashes per rotation, on 60Hz 12 flashes per : rotation. So the ring of allignment marks which are nearer together is : the 60Hz one for the U.S. I think it is marked on the drive, which I promptly ignored. I may have aligned to them European spec! : If there is only one ring of marks, count them and check for them : being 12. Thanks, for the clarification. I will check that I did in fact align the drive to 60 Hz. Eric : -- : Neil Franklin, neil@franklin.ch.remove http://neil.franklin.ch/ : Nerd, Geek, Hacker, Unix Guru, Sysadmin, Roleplayer, Mystic : Use a WIMP (Windows Icons Mouse Pulldowns) interface - : or get one with a CLUE (Command Linue User Environment)? ###### Sender: Ian Stirling From: Ian Stirling Subject: Re: Osborne I -update #4 Newsgroups: alt.folklore.computers,comp.os.cpm References: <8aj0n0$hl0@nnrp4.farm.idt.net> <8ajbfl$2m4k@edrn.newsguy.com> <6u8zzl71h8.fsf@chonsp.franklin.ch> Organization: None.. User-Agent: tin/pre-1.4-980818 ("Laura") (UNIX) (Linux/2.2.13 (i586)) Lines: 22 Message-ID: X-Abuse-Info: Please be sure to forward a copy of ALL headers X-Abuse-Info: Otherwise we will be unable to process your complaint properly X-Complaints-To: admin@usenetserver.com NNTP-Posting-Date: Wed, 15 Mar 2000 18:50:32 EST Date: Wed, 15 Mar 2000 23:50:32 GMT Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!newsfeed-zh.ip-plus.net!news.ip-plus.net!News.Amsterdam.UnisourceCS!skynet.be!portc01.blue.aol.com!newsfeed.skycache.com!cyclone1.usenetserver.com!cyclone1.usenetserver.com!news4.usenetserver.com.POSTED!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52183 Neil Franklin wrote: >Assuming these to be standard 300rpm (5r/s) drives: >On 50Hz you have 10 flashes per rotation, on 60Hz 12 flashes per >rotation. So the ring of allignment marks which are nearer together is >the 60Hz one for the U.S. 100/120Hz. Most lights connected to the AC line that pulse at all pulse twice per cycle, at the peaks. Ignore this, if the only light in the room is from the mercury arc rectifiers. -- http://inquisitor.i.am/ | mailto:inquisitor@i.am | Ian Stirling. ---------------------------+-------------------------+-------------------------- If you've been pounding nails with your forehead for years, it may feel strange the first time somebody hands you a hammer. But that doesn't mean that you should strap the hammer to a headband just to give your skull that old familiar jolt. -- Wayne Throop, during the `TCL Wars' ###### From: j-steven-york@sff.net (James Steven York) Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: Fri, 17 Mar 2000 05:14:07 GMT Organization: http://extra.newsguy.com Lines: 22 Message-ID: <38d2bdf1.46410337@enews.newsguy.com> References: <8aj0n0$hl0@nnrp4.farm.idt.net> NNTP-Posting-Host: p-394.newsdawg.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Newsreader: Forte Agent 1.5/32.452 Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!isdnet!logbridge.uoregon.edu!pln-w!spln!extra.newsguy.com!newsp.newsguy.com!enews1 Xref: chonsp.franklin.ch alt.folklore.computers:52143 It would be good to note that a 5 1/4 drive that doesn't shut off is one symptom of a reversed ribbon connector. This is easily done, as many early cables weren't "keyed" to keep you from putting them on backwards. It might also be caused by a problem with drive jumper settings. Some 5 1/4 drives are very well marked as to jumpers, others not so, and some systems (like the TRS-80 did drive selection through the cable itself. If I had to guess though, I'd think the Osborne used jumpers. Later drives used the little black "monolith" pin jumpers like you still see on boards today. Some early one used a "header" system where the jumper is a header that fits in a regular DIP IC socket. Straps across the header are broken to open individual connections. On 13 Mar 2000 15:15:44 GMT, Eric Chomko wrote: >4) on the B drive (double quote char " used to boot); the drive turns on >and spins and continues to spin until I hit reset, no error messsage and >no auto shutoff like A drive. J. Steven York - www.sff.net/people/j-steven-york - Writer Generation X Novels: Crossroads, Genogoths (coming September 2000) Bolos The Old Guard (coming soon) ###### From: Eric Chomko Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 17 Mar 2000 20:18:22 GMT Organization: IDT Internet Services Lines: 26 Message-ID: <8au3ue$3n5@nnrp4.farm.idt.net> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> NNTP-Posting-Host: u2.farm.idt.net X-Newsreader: TIN [UNIX 1.3 unoff BETA release 961025] Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!newsfeed.mathworks.com!news.idt.net!nntp.farm.idt.net!u2.farm.idt.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52086 In alt.folklore.computers James Steven York wrote: : It would be good to note that a 5 1/4 drive that doesn't shut off is : one symptom of a reversed ribbon connector. This is easily done, as I will recheck the cable. But note, that the drive does not come on when I power on the system. It comes and and stays on when I access the drive. So, at least it is selecting the drive correctly, and that would indicate a correctly connected cable. But it is worth a recheck. : many early cables weren't "keyed" to keep you from putting them on : backwards. It might also be caused by a problem with drive jumper : settings. Some 5 1/4 drives are very well marked as to jumpers, : others not so, and some systems (like the TRS-80 did drive selection : through the cable itself. If I had to guess though, I'd think the : Osborne used jumpers. Later drives used the little black "monolith" : pin jumpers like you still see on boards today. Some early one used a : "header" system where the jumper is a header that fits in a regular : DIP IC socket. Straps across the header are broken to open individual : connections. I can't seem to find and jumpers, and someone indicated that the drives cannot be swapped. IOW, drive A and drive B are manufactured as such. I did note that someone marked the B drive with a bright purple magic marker. So that does support the notion of manufactured A and B drives. Eric ###### Newsgroups: alt.folklore.computers,comp.os.cpm From: wtshyman@mb.sympatico.ca Subject: Re: Osborne I -update #4 Reply-To: wtshyman@NOUCE.mb.sympatico.ca Organization: No Unsolicited Commercial E-Mail, Please ! References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> X-Newsreader: IBM NewsReader/2 2.0 Lines: 12 Message-ID: <5aVA4.3513$1m4.62008@news1.mts.net> Date: Sun, 19 Mar 2000 00:27:45 GMT NNTP-Posting-Host: 205.200.59.100 X-Complaints-To: admin@mts.net X-Trace: news1.mts.net 953425665 205.200.59.100 (Sat, 18 Mar 2000 18:27:45 CST) NNTP-Posting-Date: Sat, 18 Mar 2000 18:27:45 CST Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!news.maxwell.syr.edu!sunqbc.risq.qc.ca!torn!canopus.cc.umanitoba.ca!news-in.mts.net!news1.mts.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52286 In <38d2bdf1.46410337@enews.newsguy.com>, j-steven-york@sff.net (James Steven York) writes: >It would be good to note that a 5 1/4 drive that doesn't shut off is >one symptom of a reversed ribbon connector. This is easily done, as >many early cables weren't "keyed" to keep you from putting them on >backwards. Quite true. However, on the Osborne 1, you can't run the drives with the cable upside down because you'll short out the power supply! The O1 very frugally used some superfluous lines in the ribbon cable as power leads. Bill ###### Newsgroups: alt.folklore.computers,comp.os.cpm From: wtshyman@mb.sympatico.ca Subject: Re: Osborne I -update #4 Reply-To: wtshyman@NOUCE.mb.sympatico.ca Organization: No Unsolicited Commercial E-Mail, Please ! References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> <8au3ue$3n5@nnrp4.farm.idt.net> X-Newsreader: IBM NewsReader/2 2.0 Lines: 30 Message-ID: Date: Sun, 19 Mar 2000 00:35:56 GMT NNTP-Posting-Host: 205.200.59.100 X-Complaints-To: admin@mts.net X-Trace: news1.mts.net 953426156 205.200.59.100 (Sat, 18 Mar 2000 18:35:56 CST) NNTP-Posting-Date: Sat, 18 Mar 2000 18:35:56 CST Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!news.maxwell.syr.edu!sunqbc.risq.qc.ca!newsflash.concordia.ca!canopus.cc.umanitoba.ca!news-in.mts.net!news1.mts.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52287 In <8au3ue$3n5@nnrp4.farm.idt.net>, Eric Chomko writes: >In alt.folklore.computers James Steven York wrote: >I can't seem to find and jumpers, and someone indicated that the drives >cannot be swapped. IOW, drive A and drive B are manufactured as such. I >did note that someone marked the B drive with a bright purple magic >marker. So that does support the notion of manufactured A and B drives. > If these are the original drives, there's a resistor package marked RN3 on the left("A") drive that operates the drive select logic. Looking at the top of the board with the speed pot facing away from you, the RN3 resistor pack is just above the place where the ribbon cable connects. Umm...this is too obvious but is the belt OK ? Spindle turns ? Is the head jammed ? The Siemens drives with a lead-screw actuator had a fault mode in which the head would step out past track 0 and stick...after a few disassembly sessions I took to tucking a carefully-bent bit of coat-hanger wire in the grille on the front of the Osborne, which I'd use to (*CAREFULLY*!) un-jam the head when this happened. Bill ( who's just acquired a Mac SE in his museum of antiquities....curses, it only has the 800 K drive and NO terminal program. How to get new software into the beast?) >Eric ###### From: louiss@gate.net (Louis Schulman) Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 19 Mar 2000 02:21:53 GMT Organization: CyberGate, Inc. Lines: 14 Message-ID: <8b1dk1$2eik$1@news.gate.net> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> <8au3ue$3n5@nnrp4.farm.idt.net> Reply-To: louiss@gate.net (Louis Schulman) NNTP-Posting-Host: tstpa1-73.gate.net X-Trace: news.gate.net 953432513 80468 207.36.8.73 (19 Mar 2000 02:21:53 GMT) X-Complaints-To: abuse@gate.net NNTP-Posting-Date: 19 Mar 2000 02:21:53 GMT X-Newsreader: IBM NewsReader/2 2.0 Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!newsfeeds.belnet.be!news.belnet.be!newsfeed.icl.net!europa.netcrusader.net!205.252.116.205!howland.erols.net!newspeer.monmouth.com!news.gate.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52275 In <8au3ue$3n5@nnrp4.farm.idt.net>, Eric Chomko writes: > >I can't seem to find and jumpers, and someone indicated that the drives >cannot be swapped. IOW, drive A and drive B are manufactured as such. I >did note that someone marked the B drive with a bright purple magic >marker. So that does support the notion of manufactured A and B drives. > I am sure the drives can be swapped, I know I have done it. What you have to do is remove the terminating resistor from what was the last drive on the cable (probably B) and move it to the other drive. The jumpers may look like a chip with little links in it. I don't remember whether Osbornes did drive select on the drive or with the cable. Louis ###### From: Eric Chomko Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 19 Mar 2000 18:42:13 GMT Organization: IDT Internet Services Lines: 41 Message-ID: <8b3725$8v7@nnrp4.farm.idt.net> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> <8au3ue$3n5@nnrp4.farm.idt.net> NNTP-Posting-Host: u1.farm.idt.net X-Newsreader: TIN [UNIX 1.3 unoff BETA release 961025] Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!isdnet!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news.idt.net!nntp.farm.idt.net!u1.farm.idt.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52324 In alt.folklore.computers wtshyman@mb.sympatico.ca wrote: : In <8au3ue$3n5@nnrp4.farm.idt.net>, Eric Chomko writes: [...] : >I can't seem to find and jumpers, and someone indicated that the drives : >cannot be swapped. IOW, drive A and drive B are manufactured as such. I : >did note that someone marked the B drive with a bright purple magic : >marker. So that does support the notion of manufactured A and B drives. : If these are the original drives, there's a resistor package marked RN3 on the left("A") : drive that operates the drive select logic. Looking at the top of the board with : the speed pot facing away from you, the RN3 resistor pack is just above the place : where the ribbon cable connects. I found RN3 on both drives. A has the pack in the single row socket, and B does not. I take it that this correct as A is the last drive on the cable as B is actually in the middle of the cable, whereas the end opposite A id connected to the main board. : Umm...this is too obvious but is the belt OK ? Spindle turns ? Is the head : jammed ? The Siemens drives with a lead-screw actuator had a fault mode The belts a present and tight, but not overly so. : in which the head would step out past track 0 and stick...after a few disassembly : sessions I took to tucking a carefully-bent bit of coat-hanger wire in the grille : on the front of the Osborne, which I'd use to (*CAREFULLY*!) un-jam the : head when this happened. "Unjamming the head" sounds intriguing as this could be a problem of one or both drives. Since you knew wjat to do with that coat hanger and I'm completely new at this notion, could you provide a tad more detail about what this procedure looks like? I rather not damage something doing a procedure until I'm sure I know what it is I'm doing. : Bill : ( who's just acquired a Mac SE in his museum of antiquities....curses, it only has : the 800 K drive and NO terminal program. How to get new software into the beast?) Mac Free Term is available on the web. Eric ###### From: Eric Chomko Newsgroups: alt.folklore.computers,comp.os.cpm Subject: Re: Osborne I -update #4 Date: 19 Mar 2000 19:47:32 GMT Organization: IDT Internet Services Lines: 29 Message-ID: <8b3ask$8v7@nnrp4.farm.idt.net> References: <8aj0n0$hl0@nnrp4.farm.idt.net> <38d2bdf1.46410337@enews.newsguy.com> <8au3ue$3n5@nnrp4.farm.idt.net> <8b1dk1$2eik$1@news.gate.net> NNTP-Posting-Host: u1.farm.idt.net X-Newsreader: TIN [UNIX 1.3 unoff BETA release 961025] Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news-ge.switch.ch!isdnet!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news.idt.net!nntp.farm.idt.net!u1.farm.idt.net!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:52362 In alt.folklore.computers Louis Schulman wrote: : In <8au3ue$3n5@nnrp4.farm.idt.net>, Eric Chomko writes: : > : >I can't seem to find and jumpers, and someone indicated that the drives : >cannot be swapped. IOW, drive A and drive B are manufactured as such. I : >did note that someone marked the B drive with a bright purple magic : >marker. So that does support the notion of manufactured A and B drives. : > : I am sure the drives can be swapped, I know I have done it. What you have : to do is remove the terminating resistor from what was the last drive on the : cable (probably B) and move it to the other drive. The jumpers may look Actually A is the last drive. And there is only the resister pack. : like a chip with little links in it. I don't remember whether Osbornes : did drive select on the drive or with the cable. The cable is straight-thru, and not like an old PC that has a twist for drive select. The drives are not SA-400s nor are they Tandon 100s; they are Siemens-100, totally different than the other two. Mainly, the power is not separate (it is contained within the single connector) as in the 4-pin Molex connector standard for all drives in the PC and Mac world since the more recent smaller drives came out. In fact, my 3.2 GB Quantum HD uses that 4 pin power connector (that thing is rivaling the RS-232 DB-25 connector for longevity). In any event, I cannot find a jumper block or its equivalent short of the resister strip. Eric