Edward J Riggs, 85706 Sturnbridge Ln, Schaumburg, IL 60173

4341362, Jul 27, 1982

Oct 23, 1980

6/199923

David O. Neathery - St. Charles IL
Edward J. Riggs - West Chicago IL

King Instrument Corporation - Westboro MA

G11B 1506
G11B 2312

242183

An electronic circuitry for regulating magnetic tape movement during loading of a predetermined length of tape paid out from a supply spool and wound into a tape cassette. The tension of the tape along its path of movement is controlled by a pair of vacuum column tension members providing a different tension at the supply spool than at the take up spool. A driving member interposes the two vacuum tension members for regulating tape movement between the same. Electronic circuitry drives the take-up spool of the cassette, the supply spool and the interposing driving member, formulating drive signals in response to the length of tape contained at the separate tension members and in anticipation of the need for tape in view of the instantaneous speed in which the tape is being pulled from a separate tension member.

4325092, Apr 13, 1982

Jul 18, 1980

6/170016

David O. Neathery - Wheaton IL
Edward J. Riggs - West Chicago IL

King Instrument Corporation - Westboro MA

G11B 525
G11B 502

360119

An improved cue signal detector is provided for detecting on a magnetic tape which moves at greatly varying speeds a cue signal having a fixed wavelength longer than the wavelengths of other recorded information signals. The cue signal detector comprises a pick-up magnetic head for sensing a recorded cue signal, an integrator connected so that the signal output of the pick-up head is integrated with respect to time, and an amplitude level sensor for monitoring the integrator output with respect to a reference amplitude and generating a cue output signal indicative of the detection of the cue signal on the tape when the amplitude of the integrator output exceeds a predetermined level. The output of the level sensor is processed by a filter circuit to determine whether the cue signal is valid or was generated by noise.

4386285, May 31, 1983

Oct 31, 1980

6/202669

David O. Neathery - St. Charles IL
Edward J. Riggs - West Chicago IL

King Instrument Corporation - Westboro MA

H03K 1756
H03K 342

307311

An operational amplifier for generating an output analog signal at an output node representative of an analog signal fed to the non-inverting input of the operational amplifier. A controllable switch connects the output of the operational amplifier to the output node, and the signal at the output node is fed back to the inverting input of the operational amplifier. The controllable switch is responsive to a digital logic control signal for completing the circuit path between the operational amplifier and the output node in order to generate the output analog signal. A plurality of such operational amplifiers have their feedback path connected at a common output node.