Well the data are still there and could be retrieved with a sophisticated servo on data system and/or a probe head on the data surfaces. Simpler to hit the spindle motor top dead center with a very large hammer ruining the bearings and crashing a few heads in the process. Even then the data are still there so nothing beats a multi-pass full disk wipe
-----Original Message----- From: Chris Zach [mailto:c...@beaker.crystel.com] Sent: Thursday, March 23, 2023 9:53 AM To: cctalk@classiccmp.org Subject: [cctalk] Re: Nuking an MFM drive with a magnet, format/servo gone? Speaking from experience with an old RD54, yep. Put a magnet on the outside case towards the bottom, spin the drive up and it's gone forever. On 3/23/2023 12:22 PM, Daniel Daigle via cctalk wrote: > Old MFM/RLL drives with stepper positioners generally have no servo. > The same can't be said of voice-coil positioned drives; they could use > any means, including hardware optical servos, etc. but often used a > surface and a head for that purpose... so yes, you can render one of > these drives useless with a magnet if yours has a servo surface. (This > is not the same as embedded servo, which places servo information > -with- the data on the same surfaces.)
