Battling with an Apple ProFile drive

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Battling with an Apple ProFile drive

Postby tezza on Mon Jan 23, 2012 9:19 pm

I picked up a non-working Lisa ProFile drive as part of Don's (Antiphrasis) vintage sell-off. I've made some progress with it. After making a cabel, replacing a couple pf PSU capacitors, cleaning contacts and reseating that which could be reseated it now gets through it's self-check on startup. Furthermore it's actually booted four times to reveal MacWorks XL 3.0 on the drive!

However, it not as rosy as it sounds. It's booted 4 times in about 200 tries so that's not a good strike rate. The fact that it's done it even once though gives me hope. For some reason when the computer itself accesses the drive, the stepper motor doesn't want to move (except backwards maybe). It's not getting the data it should. This may be a long term project I think...good for those winter evenings.

I've very pleased with the drive Don. It's in great physical condition, sounds smooth and goes well with my second Lisa 2. Hopefully given time and work, I'll eventually get it working 100%.
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Re: Battling with an Apple ProFile drive

Postby Gibsaw on Tue Jan 24, 2012 2:29 pm

tezza wrote:I picked up a non-working Lisa ProFile drive as part of Don's (Antiphrasis) vintage sell-off. I've made some progress with it. After making a cabel, replacing a couple pf PSU capacitors


Came across some brand new profile psu's on my ebay watchlist. Not sure if that's any help.
"dsakey" on trademe. Apple II's are my thing.
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Re: Battling with an Apple ProFile drive

Postby tezza on Tue Jan 24, 2012 2:36 pm

Thanks but no, it's not the PSU. That's as steady as a rock with the correct voltages and no sign of ripple. It did need a couple of AC filter capacitors replacing of course (you know, the smoke and pop show) :) It's fine now though.

The encouraging thing is that the drive itself seems ok. The problem points to something on the two circuitboards, most likely the disk controller board. If only I have a working equilvalent to use as a reference, it would make diagnosis so much easier.
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Re: Battling with an Apple ProFile drive

Postby tezza on Tue Jan 24, 2012 2:39 pm

The fact that it (in a blue moon) does work, I suspect a connection...maybe a bad socket even although they all look pretty sound. Or it could be that things are just over the edge of tolerance except very occasionally...maybe a bad cap somewhere then?
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Re: Battling with an Apple ProFile drive

Postby Carcenomy on Tue Jan 24, 2012 4:27 pm

Something I have noticed with the early drives is that bad mechanicals can cause drama. I had a pair of what should have been working Compaq C2244 500MB SCSI-2 drives, both gave me a whiffy cloud of magic smoke after attempting to spin up, motors had seized and the controller didn't think to stop trying to spin them. Seems stalling a hard drive motor has wicked consequences on the controller :lol:

The WD XT-IDE drives I have from my A590 and PC10 both show strange issues mechanically too... the A590 example feels like its head position stepper is binding and causing issues. The PC10's unit I did get to respond, but it died a short while later. They're of similar vintage to your Profile's drive...
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Re: Battling with an Apple ProFile drive

Postby tezza on Tue Jan 24, 2012 7:16 pm

Yea, they can be temperamental allright. What give me hope here though is that the self check seems to work just fine. The stepper steps and checks every track then returns to it's rest position...as it should. That would indicate the actual mechanics are ok. It's just when the computer tries to tell it what to do, when things go awry.
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Re: Battling with an Apple ProFile drive

Postby tezza on Thu Jan 26, 2012 8:35 pm

Well, I tried reinstalling Lisa Office 3.1. Lights blinked, stepper motors chatted then the system told me it couldn't find a usable attached disk. So I couldn't even initialise the Profile. The machine does know the drive is there because it comes up as an icon on manual boot.

As one guy on the Lisa list mailing list hypothesised. It's almost like the stepper is getting corrupt data and is trying to go backwards to position zero even when it is AT position zero (which is why it clatters and vibrates at the rest position). It THINKS it's positioned somewhere else and is trying to go back to track 0. The RAM on the board is ok 'cause I swapped that out.

A job for a 'scope and those long winter nights methinks. My hunch? A crook socket, capacitor or perhaps a failing chip on the disk controller board.
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