RK06 alignment pack

[Jon Elson]

On 06/17/2015 11:56 AM, Johnny Billquist wrote:
> On 2015-06-17 18:36, Pontus Pihlgren wrote:
>> How was alignment packs produced?
>
> As far as I know, in special machines mounted on slabs on stone 
> weighting tons, standing on dampeners, so that you had absolutely 
> vibration free environment, and then a very precisely controlled head 
> control system that could write the tracks at the exact place they 
> should be. I think the alingment packs even have some tracks 
> intentionally offset from true center in order to check signal 
> strength when heads are slightly off track as well.
>
These pack formatters used air bearings to give the most vibration-free 
rotation of the spindle.
They were generally pretty open units, not like disk drives, and were 
run in clean rooms by people wearing low-dust overalls.

Jon