Portable terminal device for automatically controlling transmitting voice level and calling sound level

A comparing unit 18, when a radio unit 1 receives a radio signal, compares an ambient noise level detected by a noise sensor 17 with a preset threshold value. If the ambient noise level is smaller than the threshold value, the comparing unit 18 outputs a set value signal SH, and sets a receiving voice level set value of a receiving voice level setting unit 19 to "SMALL", a transmitting voice level set value of a transmitting voice level setting unit 20 to "LARGE" and a calling sound level set value of a calling sound level setting unit 22 to "SMALL", respectively. By contrast, if the ambient noise level is larger than the ambient noise level, the comparing unit 18 outputs the set value signal SH and sets the receiving voice level set value of the receiving voice level setting unit 19 to "LARGE", the transmitting voice level set value of the transmitting voice level setting unit 20 to "SMALL" and the calling sound level set value of the calling sound level setting unit 22 to "LARGE", respectively.