Technician License Class
1 / 40

Presented by Heart Of Texas Amateur Radio Club (HOTARC) - PowerPoint PPT Presentation

  • Uploaded on

Technician License Class Gordon West Technician Class Manual Pages 115-131 Digital Signals & Space Communications. Presented by Heart Of Texas Amateur Radio Club (HOTARC). Internet and Amateur Radio. See pages 122 – 123… Key words: Internet IRLP = Internet Radio Linking Project

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' Presented by Heart Of Texas Amateur Radio Club (HOTARC)' - delila

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Technician License ClassGordon West Technician Class ManualPages 115-131Digital Signals & Space Communications

Presented by

Heart Of Texas Amateur Radio Club


Internet and amateur radio
Internet and Amateur Radio

  • See pages 122 – 123…

  • Key words:

    • Internet

    • IRLP = Internet Radio Linking Project

    • Echolink voice over Internet

    • T6 A03: gateway to the Internet

Weak Signals, Digital Communications

T6a03 pg 122
T6A03 (pg 122)

  • What name is given to an amateur radio station that is used to connect other amateur stations to the Internet?

    • A gateway

    • A repeater

    • A digipeater

    • A beacon station

Weak Signals, Digital Communications


Weak Signals, Digital Communications

T6b02 pg 123
T6B02 (pg 123)

  • What does the abbreviation IRLP mean?

    • Internet Radio Linking Project

    • Internet Relay Language Protocol

    • International Repeater Linking Project

    • International Radio Linking Project

Weak Signals, Digital Communications

T6b05 pg 123
T6B05 (pg 123)

  • What method is used to transfer data by IRLP?

    • VHF Packet radio

    • PSK31

    • Voice over Internet protocol

    • None of these answers are correct

Weak Signals, Digital Communications

T6b11 pg 123
T6B11 (pg 123)

  • When using a portable transceiver how do you select a specific IRLP node?

    • Choose a specific CTCSS tone

    • Choose the correct DSC tone

    • Access the repeater autopatch

    • Use the keypad to transmit the IRLP node numbers

Weak Signals, Digital Communications

T6b10 pg 123
T6B10 (pg 123)

  • Where might you find a list of active nodes using VoIP?

    • The FCC Rulebook

    • From your local emergency coordinator

    • A repeater directory or the Internet

    • The local repeater frequency coordinator

Weak Signals, Digital Communications

T6b07 pg 123
T6B07 (pg 123)

  • Which one of the following allows computer-to-radio linking for voice transmission?

    • Grid modulation

    • EchoLink

    • AMTOR

    • Multiplex

Weak Signals, Digital Communications

T6b03 pg 124
T6B03 (pg 124)

  • Who may operate on the Echolink system?

    • Only club stations

    • Any licensed amateur radio operator

    • Technician class licensed amateur radio operators only

    • Any person, licensed or not, who is registered with the Echolink system

Weak Signals, Digital Communications

T6b01 pg 124
T6B01 (pg 124)

  • How is information transmitted between stations using Echolink?

    • APRS

    • PSK31

    • Internet

    • Atmospheric ducting

Weak Signals, Digital Communications

T6b08 pg 124
T6B08 (pg 124)

  • What are you listening to if you hear a brief tone and then a station from Russia calling CQ on a 2-meter repeater?

    • An ionospheric band opening on VHF

    • A prohibited transmission

    • An Internet linked DX station

    • None of these answers are correct

Weak Signals, Digital Communications

Packet radio
Packet Radio

  • See pages 124 – 125…

  • Key words:

    • Packet

    • Terminal

    • Sound card (in your computer)

  • What is a packet system?

Weak Signals, Digital Communications

A packet system
A Packet System

Key ideas:

  • Use radios to connect computers (digital communications), just as telephone lines were used in the past.

  • Instead of a modem, we use a device called a Terminal Node Controller, or TNC.

  • Since computers are doing the talking, there is no need for a microphone in a packet system.

Weak Signals, Digital Communications

A packet system1
A Packet System

(The Old Way)





Weak Signals, Digital Communications

A packet system2
A Packet System

(The New Way)





Weak Signals, Digital Communications

T6 c01 pg 124
T6 C01 (pg 124)

  • Which of the following is an example of a digital communications method?

    • Single sideband voice

    • Amateur television

    • FM voice

    • Packet radio

One of many types of computer-to-computer radio communications

Weak Signals, Digital Communications

T5 a08 pg 125
T5 A08 (pg 125)

What is connected between the transceiver and computer terminal in a packet radio station?

  • Transmatch

  • Mixer

  • Terminal Node Controller

  • Antenna

Usually known as aTNC

Weak Signals, Digital Communications

T5 a09 pg 125
T5 A09 (pg 125)

Which of these items is not required for a packet radio station?

  • Antenna

  • Transceiver

  • Power source

  • Microphone

Weak Signals, Digital Communications

T5 a10 pg 125


T5 A10 (pg 125)

What can be used to connect a radio with a computer for data transmission?

  • Balun

  • Sound Card

  • Impedance matcher

  • Autopatch


Weak Signals, Digital Communications

T5 d13 pg 126
T5 D13 (pg 126)

  • What is one of the reasons to use digital signals instead of analog signals to communicate with another station?

    • Digital systems are less expensive than analog systems

    • Many digital systems can automatically correct errors caused by noise and interference

    • Digital modulation circuits are much less complicated than any other types

    • All digital signals allow higher transmit power levels

Weak Signals, Digital Communications

a “waterfall” display showing several PSK QSOs occurring


  • See pages 126…

  • Key words:

    • Low-rate (i.e., slow) data

    • Phase Shift Keying

  • Two questions you might see…

Weak Signals, Digital Communications

T6 c07 pg 126
T6 C07 (pg 126)

  • What is PSK31?

    • A high-rate data transmission mode used to transmit files

    • A method of reducing noise interference to FM signals

    • A type of television signal

    • A low-rate data transmission mode that works well in noisy conditions

Weak Signals, Digital Communications

T6 c06 pg 126
T6 C06 (pg 126)

  • What does the abbreviation PSK mean?

    • Pulse Shift Keying

    • Phase Shift Keying

    • Packet Short Keying

    • Phased Slide Keying

Weak Signals, Digital Communications

Gps and amateur radio
GPS and Amateur Radio

  • See pages 126 – 127…

  • Key words:

    • Position

    • Global positioning system (GPS)

  • Two questions you might see…

Weak Signals, Digital Communications

T6 c02 pg 126
T6 C02 (pg 126)

  • What does the term APRS mean?

    • Automatic Position Reporting System

    • Associated Public Radio Station

    • Auto Planning Radio Set-up

    • Advanced Polar Radio System

Weak Signals, Digital Communications

T6 c03 pg 127
T6 C03 (pg 127)

  • What item is required along with your normal radio for sending automatic location reports?

    • A connection to the vehicle speedometer

    • A connection to a WWV receiver

    • A connection to a broadcast FM sub-carrier receiver

    • A global positioning system receiver

Weak Signals, Digital Communications

Satellites and amateur radio
Satellites and Amateur Radio

  • See pages 127 – 131…

  • Key words:

    • AMSAT

    • Any amateur

    • Satellite sub-bands

  • You’ll get one of these questions…

Weak Signals, Digital Communications

T7 b08 pg 127
T7 B08 (pg 127)

What is the name of the group that coordinates the building and/or launch of the largest number of amateur radio satellites?

  • NSA

  • USOC


  • FCC

    Note: This is one time where the “FCC” is notthe correct choice.

“SAT”  satellite

Weak Signals, Digital Communications

T7 b06 pg 127
T7 B06 (pg 127)

  • What should you use to determine when you can access an amateur satellite?

    • A GPS receiver

    • A field strength meter

    • A telescope

    • A satellite tracking program

  • There are many free programs—just download them!!

Weak Signals, Digital Communications

T7 b01 pg 128
T7 B01 (pg 128)

  • What class of license is required to use amateur satellites??

    • Only Extra class licensees can use amateur radio satellites

    • General or higher class licensees who have a satellite operator certification

    • Only persons who are AMSAT members and who have paid their dues

    • Any amateur whose license allows them to transmit on the satellite uplink frequency

  • We’ll see also T7B04 on pg 131—again, any amateur!

Weak Signals, Digital Communications

T7 b02 pg 128
T7 B02 (pg 128)

  • How much power should you use to transmit when using an amateur satellite?

    • The maximum power of your transmitter

    • Theminimum amount of power needed to complete the contact

    • No more than half the rating of your linear amplifier

    • Never more than 1 watt

  • For any contact, always use the minimum power necessary.

Weak Signals, Digital Communications

T7 b09 pg 130
T7 B09 (pg 130)

  • What is a satellite sub-band?

    • A special frequency for talking to submarines

    • A frequency range limited to Extra Class licensees

    • A portion of a band where satellite operations are permitted

    • An obsolete term that has no meaning

  • Since satellite signals are weak, we keep them in a separate portion of the band—easier to hear!

Weak Signals, Digital Communications

T7 b10 pg 130
T7 B10 (pg 130)

  • What is the satellite sub-band on 70-cm?

    • 420 to 450 MHz

    • 435 to 438 MHz

    • 440 to 450 MHz

    • 432 to 433 MHz

  • You just have to memorize this, but notice that:

  • 35 + 35 = 70

Weak Signals, Digital Communications

T7b05 pg 127
T7B05 (pg 127)

  • What is a satellite beacon?

    • The primary transmit antenna on the satellite

    • An indicator light that that shows where to point your antenna

    • A reflective surface on the satellite

    • A signal that contains information about a satellite

Weak Signals, Digital Communications

T7b03 pg 129
T7B03 (pg 129)

  • What is something you can do when using an amateur radio satellite?

    • Listen to the Space Shuttle

    • Get global positioning information

    • Make autopatch calls

    • Talk to amateur radio operators in other countries

Weak Signals, Digital Communications

T7b07 pg 129
T7B07 (pg 129)

  • What is Doppler shift?

    • A change in the satellite orbit

    • A mode where the satellite receives signals on one band and transmits on another

    • A change in signal frequency caused by motion through space

    • A special digital communications mode for some satellites

Weak Signals, Digital Communications

Doppler shift
Doppler Shift

Doppler shift is a change in frequency as an object moves. The wave in front of the object is compressed, and expanded behind.

To a fixed observer, the shortened wavelength in front causes the frequency to increase. As the object passes overhead, the longer wavelength behind will cause the frequency to decrease (lower value).

The observer will need to adjust his radio accordingly during the pass.

Weak Signals, Digital Communications

T7b11 pg 129
T7B11 (pg 129)

  • What do the initials LEO tell you about an amateur satellite?

    • The satellite battery is in Low Energy Operation mode

    • The satellite is performing a Lunar Ejection Orbit maneuver

    • The satellite is in a Low Earth Orbit

    • The satellite uses Light Emitting Optics

Weak Signals, Digital Communications

T7b04 pg 131
T7B04 (pg 131)

  • Who may make contact with an astronaut on the International Space Station using amateur radio frequencies?

    • Only members of amateur radio clubs at NASA facilities

    • Any amateur with a Technician or higher class license

    • Only the astronaut's family members who are hams

    • You cannot talk to the ISS on amateur radio frequencies

Weak Signals, Digital Communications