FW: RK05 question

David> More seriously. I wonder how good the rotational stability is David> on the drive. Mny of the reasons for using "hard sectored" David> media was because a) Drives "wobbled", and b) Accurate timing David> electronics were "difficult". I think the motor is the kind whose rotation speed is tied to the power line frequency, so assuming normal stable utility power the rotational stability will be excellent. Also, the motor power is fairly low compared to the inertia of the disk, so any short term variations in motor power have only a small effect on RPMs. David> If the drive motor speed is stable (over the course of a David> rotation), it*MIGHT* be possible to alter a drive to just use David> the "home" slit and synthesize the individual sectors. Never David> tried this with an RK05 [heck havent touched one of them in David> over 25 years!], but I have used this technique to synchronize David> otgher items..... I suppose that's possible. One way to do it would be to build a PLL that's locked to the start of track pulse, and derive a 12x or 16x sector clock from that. Or, analogously, you could use a PLL to derive a 16 sector clock from the 12 sector clock (multiple by 4/3rd, not hard with a PLL). That's probably a good solution... paul