proposals new style of presentation & educationD live broadcasting system by one-man-operation
proposed by Prof.Satoshi Nishimura / Jichi Med Univ(JAPAN)

tech fixing broken HDD how to assemble and disassemble
proposed by Prof.Satoshi Nishimura / Jichi Med Univ(JAPAN)

second, motor drive board was replaced
new HDD (contol) was used as "doner"
because MBR (master boot recored) was memorized into small ROM chip
chip was removed from damaged one to new healthy board

however, in this case, condition was not changed
thus, disc itself or motor should be the cause of problem