This shield circuit allows recording of the signal from a serial output on a cassette recorder, with excellent signal quality. We took advantage of only half of the 74LS74, which consists of a double D-type flip-flop. 4013, a double D-type flip-flop, can also be used, but in CMOS technology. The supply is made with a voltage of 5 V. The input cable to the recorder must be short and shielded, so that there is no deformation of the signal to be recorded.
