MTS51 schematic for speaker control, values of components.

Discussion in 'Homework Help' started by evol_w10lv, Dec 6, 2014.

  1. evol_w10lv

    Thread Starter New Member

    Feb 19, 2013
    I'm doing a little project on MTS51 Microcomputer trainer using speaker. The task is to make schematic for my circuit and explaine values. We are using RS232 to connect MTS51 to PC.
    So here's my circuit:
    I can explaine why there're diode D1, transistor T1.. but it's not clear, whats the main reason for 74LS14 there? And also, why R1 = 820 Ohms. I don't know model of the speaker, so I don't know Ic and speakers resistance, but as I know max possible current values of D1, T1... i can guess, that Ic is lower than 500mA. And how invertor 74LS14 effects base current?