Hi Mike, The Bernoulli disks definitely do use servo, so as you say, if the servo patterns are damaged the data is toast.
Do you have any advice on head cleaning? The docs on the second-generation drive (Alpha-10H) just say to use a cleaning cartridge, and I don't have one. I've cleaned floppy drive heads with isopropyl and a lint-free swab, but I'm reluctant to do this to the Alpha-10 without advice from someone who's done it. Best regards, Eric
