Re: MFM drive gone nuts

From: Michał Pleban <>
Date: Tue, 22 Jul 2014 11:07:57 +0200
Message-ID: <>

MikeS wrote:

> 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 load.

That was the case with the 610 power supply which was too weak to spin
the drive, but the 710 power supply worked well. I sure hope I did not
stick the heads to the platter when I was moving the machine... on every
power up the drive backed up the head to the "0" position so hopefully
it was not the case.

> 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.

The connector looks good and at least the +5V is applied because the
drive board reports the error. I will unscrew the board from the
mechanics and measure the +12V in various places.


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Received on 2014-07-22 10:01:17

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