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SarahWalker
August 24th, 2017, 09:33 AM
Hi everyone! Hope this is the right place for this post.

I recently bought a Seagate ST-4096 drive. Plugged it in, powered on, the LED at the front came on but no other signs of life. Some inspection revealed a burnt out SMD component (I think a resistor?) on the PCB. Unfortunately there isn't enough of it left to tell what it was, and in any case none of the other SMD resistors on the board seem to have any markings on. So my questions now are :

1. Is there anyone with an ST-4096 who can confirm if this actually is a resistor, and what value it is? (I figured this would be the best forum to ask)
2. Is this actually worth trying to fix? I'm assuming that this burnt out for a reason, and I've no idea if the drive mechanically works at all... If it is likely to be dead then I didn't spend very much on it, so don't mind turning it into a paperweight!

Thanks!

pcdata76
August 27th, 2017, 10:17 AM
Welcome to VCF

Unfortunately i don't own a ST-4096 to check the component, but if i were you i would definitely try to fix it. It could be burnt due to some accidental short. I managed to revive a similar MFM drive with broken mosfet by transplanting from a mechanically dead drive.

Does it spin up when you've applied the power?

Druid6900
August 28th, 2017, 07:47 AM
Hi everyone! Hope this is the right place for this post.

I recently bought a Seagate ST-4096 drive. Plugged it in, powered on, the LED at the front came on but no other signs of life. Some inspection revealed a burnt out SMD component (I think a resistor?) on the PCB. Unfortunately there isn't enough of it left to tell what it was, and in any case none of the other SMD resistors on the board seem to have any markings on. So my questions now are :

1. Is there anyone with an ST-4096 who can confirm if this actually is a resistor, and what value it is? (I figured this would be the best forum to ask)
2. Is this actually worth trying to fix? I'm assuming that this burnt out for a reason, and I've no idea if the drive mechanically works at all... If it is likely to be dead then I didn't spend very much on it, so don't mind turning it into a paperweight!

Thanks!

1. Get a hold of MikeS on here. I just sold him one and, with a picture, he could confirm the value.
2. You won't know until you replace it and look for any traces that look like they've been heated.

Al Kossow
August 28th, 2017, 08:14 AM
it appears to match the one above the 7407
it may be a ferrite, only thing stamped on it is a "T"40499

MikeS
August 28th, 2017, 09:32 AM
1. Get a hold of MikeS on here. I just sold him one and, with a picture, he could confirm the value.

I've got three of them; not very convenient to get at so I was waiting for someone else to answer, but since I've been called out... ;-) :
The boards are all different and none looks exactly like the pic but one does have what looks like a ferrite as Al suggests; no markings at all on mine.

fatwizard
August 31st, 2017, 04:27 PM
I happened to have a 4096 on the work bench right now. The part of the board in question looks exactly like the OP's picture, but sadly there are no markings on the part.

MicrocomputerSolutions
August 31st, 2017, 11:24 PM
The early versions of the ST4096 featured a horse shoe shaped logic board on the top of the drive, besides the board located on the bottom. I sold a boat load of those early ST4096 drives (with the top mounted logic board) to Compupro Owners. AND every stinking one of them died almost exactly 90 days after I installed them. When I returned them to Seagate for Warranty Repair, I was quoted 11-12 months waiting for a reconditioned replacement drive. I could buy new drives off the shelf, but Seagate would not replace the dead drives with new ones.

I ended up buying new CDC drives for my Customers at my expense, and waiting for the replacement Seagate drives, (which I sold at a loss when I finally got them). Fot this reason I will not have anything to do with those early Seagate full height 40XX Series drives.

If you really want to try to fix the drive, I'd look for a replacement logic board from a scrapped ST4096 drive.

SarahWalker
September 3rd, 2017, 09:06 AM
Thanks for the advice people!

Unfortunately I've concluded this probably isn't worth trying to fix. I did some more testing before ordering any parts, and it's intermittent whether the drive will spin up or not, and it makes a horrible noise instead of seeking. I decided it was probably dead and opened it up, and there seems to be some corrosion around the seek mechanism, suggesting it's probably past my abilities to repair.

It will make an interesting desk ornament at work I suppose!