Analog Systems:
When we thing of
voice systems the very first thing that comes into our mind is a home phone.
Like our home phones our old telephony systems used to operate in analog mode.
It has two cables Ring and Tip and it operates on -48 DC voltage. When the circuit
between the two gets complete it withdraws a dial tone from the central office.
The voice waveform of these kind of calls are analog waveform.