Abstract: An automatic sheet transport mechanism for precisely positioning a sheet relative to an automatic signature writing machine or the like is disclosed. A writing instrument is located vertically above a flat writing surface upon which the sheet rests and is movable into and out of engagement with the writing surface in a defined writing area. A sheet positioning device accurately positions the sheet laterally on the writing surface. A sheet feeding device is also provided for moving a single sheet from a stack of sheets and for advancing the single sheet to the sheet positioning device. A control device cyclically operates the transport mechanism so that the single sheet is moved by the sheet feeding device and sheet positioning device to the writing area of the writing surface where the writing takes place and thereafter the sheet positioning device is actuated to move the single sheet off of the writing surface so that the cycle can be repeated.

Abstract: An improved method and apparatus for reducing wow and flutter associated with recording devices are disclosed. Two input signals containing useful information and a constant reference signal are recorded and reproduced by a three channel recording and reproducing system. The reproduced signals contain, in addition to the recorded signals, frequency deviations caused by wow and flutter of the recording and reproducing system. Reproduced signals are converted to frequency-dependent voltages and the constant reference signal is subtracted from the reproduced reference voltage to provide a reference error voltage. The reference error voltge is transmitted to a multi-state control circuit in which the reference error voltage cancels the error voltage components of the two reproduced information frequency-dependent voltages leaving only the frequency-dependent information input signal voltages which are then transformed into frequency signals substantially equal to the recorded information signals.