Figure 6-8: Analog Telephone Transmission Analot (Analogous) Electrical Signal Sound Wave Analog signals rise and fall in intensity with the human voice No resistance to errors as there is in digital transmission Initially, the entire Pstn was analog 6-156-15 Figure 6-8: Analog Telephone Transmission Sound Wave Analog (Analogous) Electrical Signal Analog signals rise and fall in intensity with the human voice. No resistance to errors as there is in digital transmission. Initially, the entire PSTN was analog