The quality of radio frequency signals received at a mobile phone or cellphone is sampled. The results are employed to produce a human discernible indication such as by blinking a received signal strength bar on a display. The bar remains constant without blinking if the signal quality is at or below a preselected minimum and can have the blinking rate increase as the sensed signal quality decreases. Distortion can be determined in either the digital or analog mode. Digital signal quality can be reflected in the sensed bit error rate while the level of analog signal quality can be determined from the supervisory audio tone.