WikiVisually
The entire wiki reimagined as a visual magazine with video discovery · Watch your interests come alive
WikiVisually
The entire wiki reimagined as a visual magazine with video discovery · Watch your interests come alive
Nature The World Movies USA Top Art Fine & Rare History Ivy & Inquiry
Signal modulation
Videos
Signal modulation is the process of varying one or more properties of a periodic waveform in electronics and telecommunication for the purpose of transmitting information.
Waterfall plot of a 146.52 MHz radio carrier, with amplitude modulation by a 1,000 Hz sinusoid. Two strong sidebands at + and - 1 kHz from the carrier
Waterfall plot of a 146.52 MHz radio carrier, with amplitude modulation by a 1,000 Hz sinusoid. Two strong sidebands at + and - 1 kHz from the carrier frequency are shown.
A carrier, frequency modulated by a 1,000 Hz sinusoid. The modulation index has been adjusted to around 2.4, so the carrier frequency has small amplit
A carrier, frequency modulated by a 1,000 Hz sinusoid. The modulation index has been adjusted to around 2.4, so the carrier frequency has small amplitude. Several strong sidebands are apparent; in principle, an infinite number are produced in FM, but the higher-order sidebands are of negligible magnitude.
Modem
Videos
A modulator-demodulator, commonly referred to as a modem, is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as teleph
Signal modulation
…a device or circuit that performs modulation. A demodulator (sometimes detector) is a circuit that performs demodulation, the inverse of modulation. A modem (from modulator–demodulator), used in bidirectional communication, can perform both operations. The lower frequency band occupied by the modulation…
Acoustic coupler modems used a telephone handset as the audio medium, with the user dialing the desired number and then pressing the handset into the
Acoustic coupler modems used a telephone handset as the audio medium, with the user dialing the desired number and then pressing the handset into the modem to complete the connection. These systems generally operated at a speed of 300 bits per second.
Collection of modems once used in Australia, including dial-up, DSL, and cable modems
Collection of modems once used in Australia, including dial-up, DSL, and cable modems
A demonstration of AT&T Bell 101 modem in 1958
A demonstration of AT&T Bell 101 modem in 1958
The original 300-baud Hayes Smartmodem
The original 300-baud Hayes Smartmodem