On 1/17/23 13:58, Paul Koning via cctalk wrote: > > No, 844 drives use linear voice coils (linear motors), which seems to have > become the norm in the early 1970s. RK05 is another example. The term > "voice coil" is used because they look like oversized versions of the coil > that drives the speaker cone in loudspeakers. These all are some sort of > servo device; in many of them the servo signal is on the media, but not > always. For example, the RK05 uses a pattern of lines on a glass substrate > attached to the actuator; the "fault" light on the drive indicates a failure > of the light bulb that illuminates the servo pattern. > > A common feature of linear motor actuators is an emergency retract circuit, > powered by rather large capacitors, to pull the heads off the disk if there > is a power failure. > And, IIRC, a bit red warning sticker on the actuator.
--Chuck
