listen-in key for data recorders

EE July/August 1986 I 1 00 listen-in key for data recorders The pros and cons of using data (cassette) recorders for mass memory storage in a computer system are likely to be so well-known that any further discussion as to the relative cost efficiency of the cassette tape would seem to be superfluous. There is, however, one distinct disad- vantage to the data recorder that is relatively easy to get rid of, viz. the trouble many users experience in positioning the tape to the leader note of the desired program or file to load into the computer. Many datarecorders, while offering the highest possible save and load speed, fail to produce the sound on tape when the computer audio cable is plugged into the earphone socket, forcing the user to plug and unplug this cable in a desperate search for the program. The solution to this sorry plight con- sists of a simple combination of resistor and push to make button, which are to be built into the cassette recorder. The circuit diagram shows...