WTB: Floppy disc test/service disc

On Jan 5, 2014, at 13:19 , Fred Cisin <cisin at xenosoft.com> wrote: Off on a minor tangent, I've daydreamed about adding a positional encoder and modified servo system to a DEC RL02 drive in order to write new servo bursts to a platter that has missing/damaged servo bursts, such as from being bulk erased. The detail I don't know yet is whether the servo bursts can be written with normal heads, or if they require a different magnetic gap width (i.e., wider than normal data read/write heads). Back on the floppy subject, I think that the trickiest detail about making an alignment disk writing jig would be calibrating the micrometer reading to place the head gap at the correct radius. One way might be to get an original known-good alignment disk, calibrate the jig against it, and then use the jig to crank out new alignment disks for sale to hobbyists. I would imagine that the disk drive manufacturers had some way to measure the radius of a written track for calibration purposes in the lab? -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/