Re: MFM drive gone nuts

From: MikeS <>
Date: Mon, 21 Jul 2014 15:16:11 -0400
Message-ID: <D73509494DAC4DBD80ABC2A839BD0811@310e2>
It sure does sound like a power supply issue; I've seen very few drives that 
would not spin up when power was applied (except in cases where the head(s) 
were stuck to the platter(s)), but I've seen many instances of the power 
supply being defective or shutting down due to too heavy or too light (!!) a 

The power connector was also pretty flimsy on some drives and would fail 
after plugging it in and out a few times.

Definitely check both +5 and +12 on the drive's PC board at the connector.


----- Original Message ----- 
From: "Martin Hoffmann-Vetter" <>
To: <>
Sent: Monday, July 21, 2014 2:32 PM
Subject: RE: MFM drive gone nuts


> I went home and tried that, but after I turned the computer on,
> something very wrong happened to the drive - it does not spin. The LED
> flashes an error message, which according to the technical manual
> indicates "Index pulse not detected during spinup" which as I
> understand indicates that the drive CPU detected that it cannot spin.
> I think the drive just died :-(
> Oddly, the computer failed too and now indicates "RAM Error" on
> startup. I wonder whether these two issues are related, but I have no
> idea how.

Is there a problem with the power supply? The hard drive use the +5V and 
+12V. The dynamic RAM uses only +5V. What happens with the +5V?


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Received on 2014-07-21 20:01:03

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