No worries, it was worth a shot and I appreciate your help. I've actually learnt quite a bit so that is no bad thing. I think I'll consign this to the "might look at again some time in the future" pile. I'm sure everybody has such piles in their workshop. Mine seems to keeps growing (-: Terry ----- Original Message ----- From: "Tony Duell" <ard at p850ug1.demon.co.uk> To: <cctalk at classiccmp.org> Sent: Thursday, March 03, 2011 8:05 PM Subject: Re: Faulty Apple Lisa 2/10 Drive - Problem persists >> >> Some more progress but not good news... >> >> Unfortunately replacing those caps and the TA7259 IC hasn't made any >> difference to the 400k drives. The symptom (motor refuses to start when >> the > > >> spindle is in a certain position) is still the same in both. I don't have >> a >> circuit diagram and it may be that there are some other bits and pieces >> there, compared to later Sony drives. > > I suppoe you could always reverse-engineer the drive. It can't be _that_ > complicated. > >> >> In one of the drives, if the spindle is in a position where the motor >> starts, it will read disks...but not well. It's very slow to load >> things. >> I imagine there are lots of retries, maybe because the spindle isn't >> spinning at the speed it should. In the second drive, even when the >> motor >> does rotate, it does not load programs. It could be that this second >> (rather more tattered) drive has more than one issue. >> >> Oh well... it was worth a shot. Much obliged for the help, Tony and >> others. >> I'm not sure how further I can go with it. >> >> Anyone have any other ideas as to what might cause this problem? Maybe >> the >> motor windings themselves are just shot. > > I think it's very unlikely to be the windings. Didn;t we check that there > was roughtly teh same resistance between each piar of potor output pins > onthe vtornller IC anyeay? > > My guess (and it's only a guess) is that it's one of the hall-effect > drvicces./ These are the little things with 4 connections at the edge of > the motor can its;elf. The body of the drvice is inside the motor. They > are labelled H1, H2 and H3 on the PCB I susepct > > I think you will ahve to dismantle the motor can next. There are 2 > flexible PCB tails ('flexiprints') coming out of thit. The top one -- the > one futhest from the PCB -- thet comes out of the can almost straingth > towards the left side of the drive is the FG (speed sensing) coil. It's > soldered to a pin header with is soldered to the PCB. Desoler this header > from the PCB (no not work on the flexiprint, it is too fragile). With > that free, bend up the tabs o nthe bottom and lift the housign off > complete with the FG coil. Lift out the rotor. > > You cna now see the hall effect devices. I have no idea where you'll get > replacemetns,m but those are what I would change next. > > -tony >

Yes. One advantage of what I call 'real' troubleshooting is that you tend to pick up quite a bit of electronics knowledge along the way :-) It's a pity that we live on opposite sides of the globe. If we were nest doro to each other, I'd suggest letting me have a look at it. Needless to say it's a lot easier to do this sort of diagnosis with the device in front of you. Well, I certainly do, and it does, indeed, keep growing. There's a lot of intereting stuff I must get round to working on one day. I tend to only put stuff there if I know it's going to takr a _lot_ of time to sort out (months/years) or if I know I need parts/manuals/knowledge that I can't get at the moment but might get later. I think in my case if I had a drive with a spindle motor problem I would see it through. YMMV -tony

Well, you don;'t want to make thigns worse if there's a chance you'll get more skills later, on the other hand, I would certainly agree that 'having a go' is rarely a bad idea. Yes, you can remove them non-destructively. They have 4 pins soldered to the PCB.. There are 3 in each motor, so if you only have one bad one pwere drive,you have 4 good ones which is enough to get one motor going. Is there any way you could borrow an oscilloscope? It doesn;'t need ot be anyting fancy. What I would suggest doing is looking at the signals from the hall effect devices at the pins o the TA7259 (IIRC) chip, I think it's pins 1,2,3,4,13,14. If oyu have a ;scope with differential inputs, you could look at the difference betwene 1 and 2, 3 and 4, 13 and 14. If not, or if you're not sure about it, just look at each signal in turn using AC coupling. My guess is that as this motor is going to rotatge around 600rpm (the speed of the normal fixed-speed ones), the pulses will be a fre ms apart. This will give yoy an idea of what timebase setting to use. Anyway, what you are looking for is a signal or pair of signals that looks different to all the others. When you ahve foudn that, trace it back to a hall device and change that one. Obviously you do this before dismantling the motor. -tony

Sure. I find it's best to always have serveral projects 'on the go' so that if I am held up with one (lack of parts, tools, test gear, info, etc) I can get on with something else. In any case, when you get access to a 'scope, let me/us know and I'll give you some more information... -tony

On Mon, Mar 21, 2011 at 7:11 PM, Terry Stewart <terry at webweavers.co.nz> > Congrats! You give inspiration to those of us with dusty, yellowed Lisas hidden away in the basement somewhere :)

On 3/21/11 7:04 PM, Terry Stewart wrote: As in swapping the Z8 with a special one with a piggyback eprom?

On 3/21/11 10:40 PM, Mr Ian Primus wrote: I'm guessing from the era that this was a 2KB or 4KB Z8. Is there a possibility of replacing it with a piggybackable EPROM, but using one size larger, burning both sets of firmware into it, and driving the high-order address bit with a toggle switch? -Dave -- Dave McGuire Port Charlotte, FL

--- On Mon, 3/21/11, Dave McGuire <mcguire at neurotica.com> wrote: Yeah, it's a 2k. It would be pretty trivial to make a switchable ROM, but at the same time, it's hardly necessary. Low Level formatting needs to be done very rarely. It's not something you're likely to need to do to the same disk twice (and if you do, there is probably something wrong with the disk...) Also, you wouldn't usually want to leave the piggyback version of the Z8 in the drive. The stock chip is a maskrom Z8 - might as well put it back when you're done formatting. -Ian

On 3/21/11 7:40 PM, Mr Ian Primus wrote: The information in http://bitsavers.org/pdf/apple/disk may be of interest.

Somehow I think I will never have a Lisa 'in storage' or anywhere else for that matter. They are very rare in the UK and very expensive... As a general point, I've never really seen much advantage in this. If I am gixing a computer, I am going to need (at least) a multimeter, logic anlyser, soldering iron, etc. Havcing to use a screwdriver as well doesnt' seem lik much of a problem. I didn;t stop me fixing my Mac+ to compoentn level :-)... But neing discoraged from pulling the case, making modifications, etc, is a good reason why I would avoid a particular product. Being unable to do what _I_ like with it (as with some current Apple products) is a good enough reason for me to never want or recoemnd one. -tony

Yes. Guilty as charged. (-: However, I give myself credit for at least attempting a repair. My main aim in this hobby is to have working units to display to others, talk about and play with when I want to. It's the design and historical elements I'm interested in, and tinkering with the hardware is a (usually unavoidable) means to an end. It's good that there are people who are passionate about hardware and repair though. They have deep knowledge that's valuable in keeping these geriatric machines running. Terry (Tez)

On 23/03/11 20:05, Tony Duell wrote: I have a sign on my wall: IF IT AIN'T BROKE, DON'T FSCK WITH IT. IF IT *IS* BROKE, GET THE SCREWDRIVER! Right below it is another: DANGER BIG SCARY LASER DO NOT LOOK INTO BEAM WITH REMAINING EYE To one side is a whiteboard (!). Currently listing the best recorded and target times for capturing one entire 80tk DSHD disc using a DiscFerret and a 3.5in disc drive. And a to-do list. A big to-do list. The icing on the cake: a copy of the Xkcd "The Observable Universe, From Top to Bottom, On a Log Scale" poster. Geeky, but nicer than a boring patch of badly-painted plasterboard wall.... Don't even ask about the box of comics. Or the Great Wall of O'Reilly Books. Or the Even Bigger Box Of Elektor And Maplin Magazines From 1974 To Present Day... yeesh. "Hi, I'm Phil. I'm a geek and a hoarder. And my room is a total pig sty." -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

On 23/03/11 23:37, Alexandre Souza - Listas wrote: OK, that one's better. But how about: IF IT AIN'T BROKE, FIGURE OUT HOW IT WORKS. IF IT **IS** BROKE, FIGURE OUT HOW IT WORKED, THEN FIX IT! "That word does not mean what you think it means." -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

Tony Duell wrote: Can you drag along one of HP's more modern printers and take it to bits with an enormous hammer? I think I'd like to see photos of that :-)

I forgot to mention that another part of the tradition (which so far has never been broken) is that I put it all back togeterh again and have it working at the end of the meeting :-) The only printer I've eer done was the 7245 printer/plotter. And that is sufficiently interesting and well made that I didn't want to use a hamemr on it. I may well do things like the 9866 and 2631 sometime, again, those are interesting and well made, so I'd use a screwdriver, not a hammer, to take them apart. I can fully understnad wanting to take a hammer to many modern HP products, alas :-( You're welcome to join HPCC and do this, provided you don't spread toner or ink around the room. -tony

All the religions that I've come across require oyu to beleive in that religious system to get to their idea of heaven. As an agnostic, I don't meet any such criteria. So if there is a hereafter, I am going to end up in hades... -tony

Tony Duell wrote: keep backing yourself up, and live forever.

On Wed, 23 Mar 2011, Tony Duell wrote: At least we'll all be there together. Dante claimed that there were varying regions. "Dude! You're getting a Dell!"

On 23/03/11 20:07, Tony Duell wrote: How about this: * To get into heaven, you need to believe in $religionA or $religionB. * Everyone who doesn't believe in $religionA will go to Hell. * Equally, everyone who doesn't believe in $religionB will go to Hell. * You can't believe in both religions, because their requirements are in mutual conflicting. * Union of "people who don't follow religionA" and "people who don't follow religionB" = everyone. * Thus everyone is going to hell. * Now flip the argument around so that everyone goes to heaven... Now you have an impossibility: set of everyone going to heaven = set of everyone going to hell * This leaves the statements: Everyone goes to heaven Everyone goes to hell Which are mutually exclusive! "A curious game. The only way to win is not to play." (I wanted to put a "QED" in here, but couldn't find a good place for it...) If we're getting onto the subject of religion, I'll throw this in to the pan (with apologies to Jeff Dunham): "If I'm dead, where are my 40 virgins?" "Did your Book say the virgins would be female?" "...... Holy crap!" -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

Given that my Apple Lisa 2/10 now works (as I stole a drive from the other Lisa), I've written the project up. For those interested it is here. http://www.classic-computers.org.nz/blog/2011-03-05-rejuvenating-a-lisa2-10… Cheers Terry