EST (Basic Communications)
Cards (245)
- It is the sending, processing, and receiving of information. Communication
- The exchange of information. Communication
- INFORMATION IS ALSO KNOWN AS: Intelligence, baseband signal, audio or video signal
- THE BASIC COMMUNICATION SYSTEM: Transmitter, transmission channel, receiver
- Source of information which must be delivered over a channel. Transmitter
- It performs encoding and modulation. Transmitter
- Collection of one or more circuits or electronic devices that converts the original source information to a form more suitable for transmission. Transmitter
- BASIC COMPONENTS OF TRANSMITTER: Modulator, amplifier, oscillator
- It modulates the signal. Modulator
- It is the process of changing one or more properties of the analog carrier in proportion with the information signals. Modulation
- Information sinakay sa carrier. Modulator
- It provides power to the signal. Amplifier
- Capable of increasing the signal magnitude or amplitude without appreciably altering the signal waveform characteristics. Amplifier
- Amplifier used for carrier is Class C.
- Amplifier used for audio signal is Class A, Class B, and Class AB (Push-pull)
- Q Point of Class A: Active
- Q Point of Class B: Cutoff
- Q Point of Class AB: little above cutoff
- Q Point of Class C: below cutoff
- Maximum efficiency of Class A: 25% or 50%
- Maximum efficiency of Class B: 78.5%
- Maximum efficiency of Class AB: between class a and class b
- Maximum efficiency of Class C: 90%
- Conduction angle of Class A: 360
- Conduction angle of Class B: 180
- Conduction angle of Class AB: between 180-359
- Conduction angle of Class C: less than 180
- Distortion of Class A: low
- Distortion of Class B: high
- Distortion of Class AB: Moderate
- Distortion of Class C: very high
- Provides the carrier signal. Oscillator
- Produces a periodic waveform on its output with only the dc supply as an input. Oscillator
- It can be thought of as an amplifier that provides itself through feedback with an input signal. Oscillator
- Types of Oscillators: LC, RC, crystal
- They used parallel LC network(parallel resonant circuit or tank circuit) as frequency determining element. LC oscillator
- Oscillator that is commonly used at Higher frequencies. LC oscillator
- Types of LC oscillator: Armstrong, hartley, colpitts, clapp
- It uses tickler coil. Armstrong
- It uses tapped coil. Hartley