Patent GB-1295446-A (GB)
IPC: G09B7/04
Filed: 1969-11-17
Abstract: 1295446 Teaching machines SOC D' ETUDES TECHNIQUES ET D'ENTREPRISES GENERALES 17 Nov 1969 [26 Nov 1968] 56068/69 Heading G5G In a teaching machine, a movable record medium such as a magnetic tape 1 carries instructional items together with questions thereon and answers to the questions, the former being in audibly reproducible form and the latter in coded form. The user has an answerentering means such as a key-board 15 which, when operated, sends coded signals to a comparator wherein the users coded answer is compared with the coded correct answer derived from the record medium. In Fig. 1, a transducer 2 and amplifier 3 are used to make the recorded instructions and questions audible at earphones 7 and, on detection by the transducer of an "end-of-item" signal, a relay 5 is operated to switch the transducer output to a memory unit 10 in which the coded correct answer is registered. When this has been done, relay 5 drops out and through its contacts 11 produces a pulse output A in the circuit 12, 13, 14, the pulse controlling stopping of the tape. The code employed is a pulsed digital one, e.g. the Telex code, recorded on the tape as modulations on a suitable carrier waveform. When the user operates the keyboard 15, a similarly coded signal is entered in a memory unit 16. When it has been entered, logic circuitry 18, 19 tests for coincidence. If there is coincidence, a correct answer counter 21 and correct answer indicator 21A are operated, and an output M from OR gate 23 initiates presentation of a further item from the tape 1. If non- coincidence is detected by the circuitry 18, 19, an incorrect answer counter and indicator 24, 25 are operated and so is a further counter 26. The user then "tries again". If he is correct, the next item will be presented; if not, he will receive a further incorrect answer signal and will try yet again. After a predetermined number, e.g. three, incorrect answers to the same question have been registered by the counter 26, the apparatus proceeds automatically to the next item. The next item preferably includes the correct answer to the previous question. In Fig. 1, the instruction, question and coded answer signals are all on the same tape track. Fig. 2 (not shown) depicts a modification in which, because the coded answer signals are on a different track, two transducers replace the single transducer 2 of Fig. 1. Fig. 5 depicts a modification of the Fig. 1 system in which the relay 5 is replaced by a frequency-selective filter: this is for use in connection with a tape on which the coded answers are on the same track as the questions but recorded on a carrier whose frequency is outside the range of the acoustic signals containing the instructions and questions. Figs. 3, 4 and 6 (not shown) depict alternative embodiments: in Fig. 3, a printer has an input from the memory unit 10 of Fig. 1 and also from the key board, the printer providing a record of the user's answer to each question in juxtaposition with the correct answer, in Fig. 4, the memory unit 16 of Fig. 1 is omitted, the keyboard answer being compared step-bystep as it is given with the correct answer in the memory unit 10; and in Fig. 6, two memory units are employed as in Fig. 1 but instead of the permanently corrected logic units 18 there is a single connector which is stepped along the line of cells in each of the units 10 and 16 comparing corresponding cells in sequence. Fig. 7 (not shown) depicts the circuitry whereby operation of the keyboard produces digitally coded pulses and Fig. 8 (not shown) depicts typical pulse patterns.