A simple encoding and recording system for small group observation

A simple and inexpensive system for coding and recording interaction patterns in small groups is described. It consists of a keyboard and a standard tape recorder, and it is capable of storing sequential data using up to 36 codes. Its main application is in the study of speaker-target patterns, but it can also be used in encoding up to 12 behavioral codes, or six speakers and 6 codes. The keyboard costs less than $200 and is used with conventional tape recorders and minicomputers available at most research sites.     

Computer Technology Audio tape storage of experimental data: An application to tachistoscopic research with children

An inexpensive portable system is described for storing digital data on audio tape for later computer processing. The technique involves the use of integrated circuits and an ordinary stereo tape recorder. Each datum is converted to a binary-coded voltage level that, through a sampling device, controls the phase of a square-wave signal. Depending on whether the bit being coded is \ld0\rd or \ld1,\rd the signal recorded on one tape track is either in phase or 180 deg out of phase with a reference signal recorded on the other track. Later, the recorded tape may be played back into a computer for data analysis. An application of this technique for tachistoscopic research is described.     

Tape-recording data for a cumulative recorder and for programming interval schedules

A simple method for recording discrete events with a cassette tape recorder is described. Since the converter for the recorder is inexpensive, data for several subjects can be recorded simultaneously. The recorder-converter can also be used to program interval schedules. Cassette recorded responses for a subject can be played into a cumulative recorder.     

An economical system for collecting and reducing heart-rate data,using someone else’s small computer

Hardware and program are described for a heart-rate data collection and reduction system that uses a small computer at a time removed from the actual data collection. The system is portable and inexpensive; exclusive of the computer, it can cost under $1,500. It uses an ordinary tape recorder to record discrete signals upon each occurrence of a heart beat, and it returns edited second-by-second averages of interheart-beat intervals.     

A computer-compatible multichannel event counting and digital recording system

An inexpensive multichannel event counting digital recording system has been designed for compatibility with automated data analysis equipment. For as many as 16 channels, events are simultaneously summed over preselected repetitive time intervals and recorded. Each data entry is marked with the time of day and a code identifying each channel’s data. The data is formated to be computer compatible and is logged on inexpensive readily available digital magnetic tape cassettes.     

Editing silent hesitation from speech recordings

A simple method of increasing speech rate by shortening or removing silent hesitation from speech recordings is described. Two tape recorders and a voice key are used. The transmitting tape recorder is modified to have two playback heads in line. The onset and offset of speech signals fed from the first head, via a voice key, control the tape transport of the receiving tape recorder. The speech signals from the second playback head are fed directly to the line input of the receiving tape recorder. Time delays can be arranged so that the tape transport of the receiving machine is only in motion for the duration of the speech signals. The logic circuit of a suitable voice key with independently variable onset and offset delay times is also described.     

Magnetic tape operating systems for the PDP-8

A magnetic tape operation system (TMS) based on Digital Equipment Corporation’s 4K disk monitor system (DMS), but reconfigured to improve speed and performance on a magnetic tape, is described. The TMS is compared in organization to the DMS configured to run from DECtape. A magnetic tape system device handler for Digital Equipment Corporation’s OS-8, to allow this operating system to be ran from magnetic tape, is included.     

A simple device for the preparation of exactly aligned dichotic tapes

A system is described involving three tape recorders and a control device whereby dichotic tapes can be prepared with onset alignment accurate to a few milliseconds, or to a measured asynchrony if required. No modifications of any sort are necessary for the three tape recorders. The two channels are separately recorded in the speaker’s own time, the only requirement being that the separate words be spoken with an interword interval of 350 msec or more, to provide sufficient time for starting and stopping the system. A tone burst is placed directly on tape on another channel ahead of each word, the latter being delayed by recording in tandem through two tape recorders. The first recorder is set to the delay (echo, NAB) facility, while the tone is recorded directly on the second. Subsequently, when this is done for each item on the two speech channels, the device, described below. utilizes the tone bursts to align the two input recorders. It then rerecords each pair of words on to the third (output or dichotic) machine, to the desired synchrony/asynchrony, and interitem interval. The system can be left to align the two channels automatically. A maximum repetition rate of two dichotic pairs every 1.3 sec can be achieved with Revox A77 tape recorders.     

PROCODER: A professional tape control,coding, and analysis system for behavioral research using videotape

PROCODER is a software system for observing and coding events that have been recorded on videotape. The system uses a personal-computer-based tape controller to control a VHS tape while observations are recorded. Frequencies of events, durations of events, and calculations of inter-observer agreement of events or intervals are included. Data can be output in ASCII format for use with other statistical programs. A sample study in which the system is used is described as well.     

A computer-compatible technique for recording binary events in real time

A technique is described for recording binary stimulus and response events on computer-compatible media mich as punched-paper tape and incremental magnetic tape. A specific implementation of the technique is presented along with a consideration of programming a computer to recover the recorded data. Various extensions and limitations of the technique are also included.     

An event-coder for evoked potential studies

A device is described which has 10 input and 2 output lines. Grounding an input causes a pulse with a specific amplitude, polarity, and duration to appear on one of the output lines. Pulse parameters can be set by front-panel controls. Thus, 10 distinct events can be coded by associating a unique pulse with each event. These pulses can be recorded on one (or two) channels of a magnetic tape recorder for subsequent processing. The use of this coder in the study of event-related potentials is described.     

A prepunched master deck for the computation of square roots on IBM electrical accounting equipment

This paper presents a prepunched deck of cards to enable the extraction of square roots on standard punch card tabulating equipment. Such a deck is valuable in constructing mathematical tables which involve square roots or in obtaining standard deviations in connection with computing correlation coefficients. By using a deck of reciprocals in conjunction with the deck for square roots, correlations may be solved completely on IBM equipment.The author wishes to acknowledge the help given on machine procedures by Wallace M. Taylor, 1st Lt. A.C., Wright Field, Ohio.     

An electrophysiological method for the study of binocular rivalry

A technique is described for recording cortical evoked responses from human Ss in binocular rivalry. Each target is illuminated with flickering light at different frequencies upon a steady background. While the S continuously indicates with a response key which target he is seeing, the cortical responses are tape recorded. The tape recording is later analyzed by average response computer separately for each eye, seeing and not seeing. This simultaneous record of the functioning of both eyes eliminates confounding variables found in earlier methods. Controls are included for rivalry changes during a stimulus cycle and for S motor response time.     

A CRT blanking circuit for video terminals

A simple and inexpensive modification for the ADDS 980 video terminal is described which permits the characters displayed on the CRT to be blanked and restored (under software control). This circuit is useful in applications, such as RT measurement, where precise definition of stimulus onset is important. The technique described is general enough to be applied to a variety of other video terminals.     

Automatic recognition of sleep spindles using short-term spectral analysis

An approach tö recognize automatically sleep spindles by using short-term spectral analysis is described. The EEG signal is sampled and stored on a magnetic tape in digital form. The data is analyzed on a PDP-8 computer, and the result can be either displayed on an oscilloscope or stored on another magnetic tape for further analysis. The program is written in conversational form and provides the operator with the ability to change any parameter in the program quickly by a simple command on the Teletype keyboard.     

Programmed presentation of pure tones of different frequencies using a single oscillator

A simple and inexpensive method is described for the programmed presentation of pure tones of different frequencies using a single oscillator.     

Accurate display timing using an enhanced BASIC for the Tandy Color Computer

The general suitability of the Tandy Color Computer as an inexpensive laboratory microcomputer is discussed. A program is described that adds several useful timing-related functions to the native BASIC in the Tandy Color Computer, thus allowing BASIC to be used for programming experiments involving tachistoscopic displays and reaction times.     

Construction of a tape-controlled system of presenting visual-spatial and visual-temporal stimulus patterns for use in cross-modal and intramodal matching tests

A technique of tape construction is described for use in the generation and control of all combinations of auditory-temporal, visual-temporal, and visual-spatial stimulus patterns. This technique allows the development of a set of nine tasks for testing cross-modal and intramodal matching.