Analog Signals Fundamentals

What is an Analog Signal?

• An analog signal is a continuous signal that changes to represent a time-varying quantity.
• Example: an analog spring scale that weighs objects by pointing to a number representing the weight.

Characteristics of Analog Signals

• Can take any value on the dial, indicating a continuous signal.
• Can vary in air density, such as sound waves carrying speech or music.

Analog Signal Conversion

• Can be converted from one form of energy to another, such as AM and FM radios converting sound signals into electrical signals and then into electromagnetic waves.
• Can also be converted back, such as receiving electromagnetic waves and converting them into electrical signals and then into sound signals.

Analog Signal Storage

• Can be stored and retrieved using technologies such as chart recorders, vinyl records, and magnetic recording tapes.

Analog Applications

• Examples include rotary watches and clocks, spring scales, car speedometers, thermometers, pressure gauges, seismographs, phonographs, and AM and FM radio.

Benefits of Analog Technology

• Often simple to make, such as a spring scale.
• Can be easy to broadcast, such as AM and FM radio or TV.
• Can be easy to figure out, with visible wave patterns on vinyl records.

Drawbacks of Analog Technology

• Noise and interference can ruin the signal, especially over long distances.
• Limited bandwidth, requiring frequency separation to prevent overlap.
• Privacy issues, making it difficult to keep transmissions and recordings private.
• Space issues, with analog recording media taking up a lot of space.
• Damage issues, with analog recording media being easily damaged and time-consuming to copy.

Transition from Analog to Digital

• Despite drawbacks, analog technology enabled communication, entertainment, and scientific measurements for much of the 20th century.
• Led to the development of digital technology, driven by the need to speed up mathematical calculations during World War II.

Learn about the basics of analog signals, including their characteristics and conversion from one form of energy to another.