Return to Table of Contents Communications (Printer) Methods & Systems
Recommended course length: 3 days
Prerequisites: Basic computer & printer system component knowledge.
Target audience: Computer/Network Systems Repair & Maintenance Personnel.
Overview of Communications
Purposes
Historic
Tools
Back to Basics
Relativity, point of view
Time -vs- Frequency
Language
Numbers and Numeric
Coding
Encryption
Compression
Energy, Frequency Spectrum
Elements of Communication
Information -data, fact, val monatomic function
Message -coding, representation, language
Transmission -interchange, medium, passage
Signaling -notification, modulation, send/receive, control, impulse
Noise -interference, perturbations, distortion, obstruction
Time -begin-to-end, rate, propagation, delay, multiplex
Overview of Communication Systems
Audio
Vocal, sounds, drum, whistle, yodal Visual
Smoke, mirror, signing (hand gesturing), semaphore
Touch
Touching
Extra Sensory
Telekinesis
Early Electronic Tele ‘distant’ systems
Telegraph (telegram), telefax, telephone, teletype
Modern Electronic Systems
Radio, microwave, television, optic (fiber/laser)
Future Communications
High energy, high frequency tools
Electronic Systems
Electrical circuit
Voltage, resistance, current, (power)
Simple circuit (passive)
Flashlight, electromagnet, relay, transformer
Advanced circuit (active)
Transistor gain amplifier; classes a,b,c
Operational amplifier (open & closed loop)
filter, differenciator, integrator, detector, summing
converters, transceivers
Telephony
Telegraphic system
Simple voice circuit; switchboard, common battery, echo suppression
Advanced voice circuits, signaling (PULSE/DTMF), call routing, PBX
Analog -vs- digital circuits
MODEM
Radio, Microwave (maser), Optical (laser)
Theory
Baseband modulated
Carrier modulated; am, fm, fsk, psk, tdm, qam
Television
Theory
NTSC, HDTV
Digital Communication Aspects
Data coding; ASCII, BAUDOT, EBCIDIC
Data compression
Data transmission; SERIAL -vs- PARALLEL
Time Sync; ASYNCHRONOUS - vs- SYNCHRONOUS
Speed; BAUD, bits/sec, bytes/sec, propagation delay, thruput
Concurrent directions; FULL/HALF DUPLEX
Flow control; DTR/DSR, RTS/CTS, XON/XOFF
Protocol; BISYNC, DDCMP, SDLC, SNAP, MNP, [OS], (ETHERNET)
Error; rate, detection, correction, recovery,; PARITY, CHECKSUM, CRC
Transparency
Connection and wiring; RJ-11, RJ- 45, RJ-48, JM-8
Parallel Interface Standards
Send/receive handshaking
Time domain multiplex
Direct memory access, but-to-bus
Connections and wiring