Apple IIe disk drive lights and spins continuously

Elemenoh

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I have a IIe whose disk 1 will light up and spin indefinitely whether a disk is inserted or not. From some googling it looks like it can commonly be due be an issue with the disk controller card or analog board on the drive itself.

I swap tested with two other known working drives and a known working disk controller and tried the controllers in slots 5 and 6.

Oddly a FloppyEmu works fine with either controller card in either slot.

Voltage rails are all okay. All of the contacts were cleaned. All other expansion cards were removed. The behavior is the same whether the door is open or closed.

I'm guessing there's some issue with the logic board but not sure where to focus.

Have any recommendations?
 

Volvo242GT

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Feb 7, 2022
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Hmmm, that's weird. Usually, it's the drives that have this issue. Maybe the power suppy is a little weak, causing the drive to spin, but not read or write? If you hit control-reset, does the drive stop spinning? Also, do you hear the usual head chatter when it starts up?
 

Elemenoh

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Control reset does stop the drive motor and light. Yes the head does the track 0 chatter.

PSU looks good. Dead on voltage rails with no drives attached. The 12V rail drops to like 11.7 when the drive is attached and motor is continuously running.
 

Elemenoh

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A little progress update:

This IIe came with a Swyft card. This card disables the built-in ROM to do its own thing. But when installed in slot 3, it would prevent the computer from booting. I cleaned its socketed ICs and it successfully booted. When it did, the (empty) disk drive would only briefly light and then the motor would stop running like it should.

If a normal IIe program disk was inserted at power-on, the Swyft card seemed to revert to the IIe ROM and the drive would stay lit and spin. So, I'm suspecting an issue with the IIe ROM(s).

I pulled and cleaned all of the socketed chips on the logic board, but it didn't make a difference. All of the larger chips had dead spiders underneath (gross), so maybe they caused some permanent damage to the ROMs at some point.

Next I'm going to try to swap in known-working ROMs to see if that clears up the issue.
 

Elemenoh

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Another update:
I swapped the ROMs and tried another known-working PSU and the issue persisted.

Next I'm going to swap the whole logic board.
 

rikerjoe

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Oct 31, 2021
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@Tony359 on YT posted a video recently about restoring a drive on a //c, perhaps there are some pointers that might apply in your case? I’ve bookmarked his video for later reference when I return to my //e which is showing very similar behavior that he covers in his video.
 
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Elemenoh

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Swapping the ROMs and trying the drives on another working IIe had the same symptom --- oof.

I tried two more drives and one of them worked. So my previously known-good drives were no longer good o_O

One of the original drives started working after I re-seated its 3470. I swapped in a known-working analog board into the other drive but it still didn't work. So it has some problem with the drive head or its motor. I had already cleaned the head a bit and exercised it a bit on its track. Will try more cleaning and lubing and then on to more swap testing.
 

Tony359

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Jan 1, 2023
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My //e gave me headaches when I restored it. The drives would work intermittently. When working, they were fine. The following day they wouldn't.

Only after a while I realised that the crimped bit, where the connector is attached to the flat cable, had oxidised and moving the drives/cables around was enough to trigger a malfunction.

I open the crimp bit, cut 10mm of cable and re-crimped it using a vice. No more issues.

I am not familiar with the Swyft card but those drives should spin indefinitely if there is no disk AFAIK.

Other things you can try
- Clean the heads
- Swap the writing/reading ICs between logic boards (the writing IC is NOT needed for booting a disk)
- check the speed of the drives using the pattern on the pulley
- check the voltage with a scope, my //c had a weak 12V (dead capacitor) causing the 12V to drop to 8.7V but only for a split second, a multimeter would not be able to show that.

Let us know how it goes!
 

Elemenoh

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@Tony359 that's a good tip. Thanks

I am not familiar with the Swyft card but those drives should spin indefinitely if there is no disk AFAIK.
The Swyft card takes over the ROM and stops spinning the drive if nothing is inserted. If something is inserted it goes into normal IIe mode and boots the disk.
 
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