Presented by Heart Of Texas Amateur Radio Club (HOTARC)

Technician Technician License ClassLicense Class

Gordon West Gordon West Technician Class Technician Class ManualManualPages 115-131Pages 115-131

Digital Signals & Digital Signals & Space CommunicationsSpace Communications

Presented byPresented by

Heart Of Texas Heart Of Texas Amateur Radio ClubAmateur Radio Club

(HOTARC)(HOTARC)

Weak Signals, Digital CommunicationsWeak Signals, Digital Communications 22

Internet and Amateur RadioInternet and Amateur Radio

See pages 122 – 123…See pages 122 – 123…

Key words:Key words:

– InternetInternet

– IRLPIRLP = Internet Radio = Internet Radio Linking ProjectLinking Project

– EcholinkEcholink voicevoice over Internet over Internet

– T6 A03: T6 A03: gatewaygateway to the Internet to the Internet


T6A03 T6A03 (pg 122)(pg 122)

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

A.A. A gatewayA gatewayB.B. A repeaterA repeater

C.C. A digipeaterA digipeater

D.D. A beacon stationA beacon station


EchoLinkEchoLink


T6B02 T6B02 (pg 123)(pg 123)

What does the abbreviation What does the abbreviation IRIRLP mean?LP mean?

A.A. Internet RadioInternet Radio Linking Project Linking ProjectB.B. Internet Relay Language ProtocolInternet Relay Language Protocol

C.C. International Repeater Linking ProjectInternational Repeater Linking Project

D.D. International Radio Linking ProjectInternational Radio Linking Project


T6B05 T6B05 (pg 123)(pg 123)

What method is used to transfer data by What method is used to transfer data by IIRLP?RLP?A.A. VHF Packet radioVHF Packet radio

B.B. PSK31PSK31

C.C. Voice over Voice over InternetInternet protocol protocolD.D. None of these answers are correctNone of these answers are correct


T6B11 T6B11 (pg 123)(pg 123)

When using a portable transceiver how do you When using a portable transceiver how do you select a specific IRLP node?select a specific IRLP node?A.A. Choose a specific CTCSS toneChoose a specific CTCSS tone

B.B. Choose the correct DSC toneChoose the correct DSC tone

C.C. Access the repeater autopatchAccess the repeater autopatch

D.D. Use the keypad to transmit the IRLP node Use the keypad to transmit the IRLP node numbersnumbers


T6B10 T6B10 (pg 123)(pg 123)

Where might you find a list of active nodes using Where might you find a list of active nodes using VoIP?VoIP?A.A. The FCC RulebookThe FCC Rulebook

B.B. From your local emergency coordinatorFrom your local emergency coordinator

C.C. A repeater directory or the A repeater directory or the InternetInternetD.D. The local repeater frequency coordinatorThe local repeater frequency coordinator


T6B07 T6B07 (pg 123)(pg 123)

Which one of the following allows computer-to-Which one of the following allows computer-to-radio linking for voice transmission?radio linking for voice transmission?A.A. Grid modulationGrid modulation

B.B. EchoLinkEchoLinkC.C. AMTORAMTOR

D.D. MultiplexMultiplex


T6B03 T6B03 (pg 124)(pg 124)

Who may operate on the Echolink system?Who may operate on the Echolink system?A.A. Only club stationsOnly club stations

B.B. Any licensed amateur radio operatorAny licensed amateur radio operatorC.C. Technician class licensed amateur radio operators Technician class licensed amateur radio operators

onlyonly

D.D. Any person, licensed or not, who is registered with Any person, licensed or not, who is registered with the Echolink systemthe Echolink system


T6B01 T6B01 (pg 124)(pg 124)

How is information transmitted between stations How is information transmitted between stations using Echolink? using Echolink? A.A. APRSAPRS

B.B. PSK31PSK31

C.C. InternetInternetD.D. Atmospheric ductingAtmospheric ducting


T6B08 T6B08 (pg 124)(pg 124)

What are you listening to if you hear a brief tone What are you listening to if you hear a brief tone and then a station from Russia calling CQ on a 2-and then a station from Russia calling CQ on a 2-meter repeater? meter repeater? A.A. An ionospheric band opening on VHFAn ionospheric band opening on VHF

B.B. A prohibited transmissionA prohibited transmission

C.C. An An InternetInternet linked DX station linked DX stationD.D. None of these answers are correctNone of these answers are correct


Packet RadioPacket Radio



– PacketPacket

– TerminalTerminal

– Sound cardSound card (in your computer) (in your computer)

What is a packet system?What is a packet system?


A A PacketPacket System System

Key ideas:Key ideas:

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

Instead of a modem, we use a device called a Instead of a modem, we use a device called a

TTerminal erminal NNode ode CControllerontroller, or , or TNCTNC..

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



MODEM

TELEPHONE

MODEM

TELEPHONE

(The Old Way)



TNC

RADIO

TNC

RADIO

(The New Way)


T6 C01 T6 C01 (pg 124)(pg 124)

Which of the following is an example of a Which of the following is an example of a digital digital communicationscommunications method? method?

A.A. Single sideband voiceSingle sideband voice

B.B. Amateur televisionAmateur television

C.C. FM voiceFM voice

D.D. Packet radioPacket radio

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


T5 A08 T5 A08 (pg 125)(pg 125)

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

A.A. TransmatchTransmatch

B.B. MixerMixer

C.C. Terminal Terminal Node ControllerNode Controller

D.D. AntennaAntenna

Usually known as a

TNC


T5 A09 T5 A09 (pg 125)(pg 125)

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

A.A. AntennaAntenna

B.B. TransceiverTransceiver

C.C. Power sourcePower source

D.D. MicrophoneMicrophone


T5 A10 T5 A10 (pg 125)(pg 125)

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

A.A. BalunBalun

B.B. Sound CardSound Card

C.C. Impedance matcherImpedance matcher

D.D. AutopatchAutopatch

RADIO

TNC


T5 D13 T5 D13 (pg 126)(pg 126)

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

A.A. Digital systems are less expensive than analog Digital systems are less expensive than analog systemssystems

B.B. Many digital systems can automatically correct Many digital systems can automatically correct errors caused by noise and errors caused by noise and interferenceinterference

C.C. Digital modulation circuits are much less Digital modulation circuits are much less complicated than any other typescomplicated than any other types

D.D. All digital signals allow higher transmit power levelsAll digital signals allow higher transmit power levels


PSKPSK

See pages 126…See pages 126…


– Low-rate (i.e., slow) dataLow-rate (i.e., slow) data

– Phase Shift KeyingPhase Shift Keying

Two questions you might see…Two questions you might see…

a “waterfall” display showing several

PSK QSOs occurring


T6 C07 T6 C07 (pg 126)(pg 126)

What is PSK31?What is PSK31?

A.A. A high-rate data transmission mode used to A high-rate data transmission mode used to transmit filestransmit files

B.B. A method of reducing noise interference to A method of reducing noise interference to FM signalsFM signals

C.C. A type of television signalA type of television signal

D.D. A A low-rate data transmissionlow-rate data transmission mode that mode that works well in noisy conditionsworks well in noisy conditions


T6 C06 T6 C06 (pg 126)(pg 126)

What does the abbreviation PSK mean?What does the abbreviation PSK mean?

A.A. Pulse Shift KeyingPulse Shift Keying

B.B. Phase ShiftPhase Shift Keying Keying

C.C. Packet Short KeyingPacket Short Keying

D.D. Phased Slide KeyingPhased Slide Keying


GPS and Amateur RadioGPS and Amateur Radio



– PositionPosition

– Global positioning system (GPS)Global positioning system (GPS)

Two questions you might see…Two questions you might see…


T6 C02 T6 C02 (pg 126)(pg 126)

What does the term What does the term APRSAPRS mean? mean?

A.A. AAutomatic utomatic PPosition osition RReporting eporting SSystemystem

B.B. Associated Public Associated Public Radio StationRadio Station

C.C. Auto Planning Auto Planning Radio Set-upRadio Set-up

D.D. Advanced Polar Advanced Polar Radio SystemRadio System


T6 C03 T6 C03 (pg 127)(pg 127)

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

A.A. A connection to the vehicle speedometerA connection to the vehicle speedometer

B.B. A connection to a WWV receiverA connection to a WWV receiver

C.C. A connection to a broadcast FM sub-carrier A connection to a broadcast FM sub-carrier receiverreceiver

D.D. A A gglobal lobal ppositioning ositioning ssystem receiverystem receiver


Satellites and Amateur RadioSatellites and Amateur RadioSee pages 127 – 131…See pages 127 – 131…Key words:Key words:– AMSATAMSAT– Any amateurAny amateur– Satellite sub-bandsSatellite sub-bands

You’ll get one of these questions…You’ll get one of these questions…


T7 B08 T7 B08 (pg 127)(pg 127)

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

A.A. NSANSA

B.B. USOCUSOC

C.C. AMAMSATSAT

D.D. FCCFCC

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

“SAT” satellite


T7 B06 T7 B06 (pg 127)(pg 127)

What should you use to determine when you can What should you use to determine when you can access an amateur satellite?access an amateur satellite?A.A. A GPS receiverA GPS receiverB.B. A field strength meterA field strength meterC.C. A telescopeA telescopeD.D. A satellite A satellite

tracking programtracking program

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


T7 B01 T7 B01 (pg 128)(pg 128)

What class of license is required to use amateur What class of license is required to use amateur satellites??satellites??A.A. Only Extra class licensees can use amateur radio Only Extra class licensees can use amateur radio

satellitessatellitesB.B. General or higher class licensees who have a General or higher class licensees who have a

satellite operator certificationsatellite operator certificationC.C. Only persons who are AMSAT members and who Only persons who are AMSAT members and who

have paid their dueshave paid their duesD.D. Any amateurAny amateur whose license allows them to whose license allows them to

transmit on the satellite uplink frequencytransmit on the satellite uplink frequency

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


T7 B02 T7 B02 (pg 128)(pg 128)

How much power should you use to transmit How much power should you use to transmit when using an amateur satellite?when using an amateur satellite?A.A. The maximum power of your transmitterThe maximum power of your transmitterB.B. TheThe minimum amountminimum amount of power needed of power needed

to complete the contactto complete the contactC.C. No more than half the rating of your linear No more than half the rating of your linear

amplifieramplifierD.D. Never more than 1 wattNever more than 1 watt

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


T7 B09 T7 B09 (pg 130)(pg 130)

What is a satellite sub-band?What is a satellite sub-band?

A.A. A special frequency for talking to submarinesA special frequency for talking to submarines

B.B. A frequency range limited to Extra Class A frequency range limited to Extra Class licenseeslicensees

C.C. A portion of a band where satellite A portion of a band where satellite operations are permittedoperations are permitted

D.D. An obsolete term that has no meaningAn obsolete term that has no meaning

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


T7 B10 T7 B10 (pg 130)(pg 130)

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

A.A. 420 to 450 MHz420 to 450 MHz

B.B. 435 to 438 MHz435 to 438 MHz

C.C. 440 to 450 MHz440 to 450 MHz

D.D. 432 to 433 MHz432 to 433 MHz

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

3535 + + 3535 = 70 = 70


T7B05 T7B05 (pg 127)(pg 127)

What is a satellite beacon?What is a satellite beacon?A.A. The primary transmit antenna on the satelliteThe primary transmit antenna on the satellite

B.B. An indicator light that that shows where to point An indicator light that that shows where to point your antennayour antenna

C.C. A reflective surface on the satelliteA reflective surface on the satellite

D.D. A signal that contains information about a A signal that contains information about a satellitesatellite


T7B03 T7B03 (pg 129)(pg 129)

What is something you can do when using an What is something you can do when using an amateur radio satellite?amateur radio satellite?A.A. Listen to the Space ShuttleListen to the Space Shuttle

B.B. Get global positioning informationGet global positioning information

C.C. Make autopatch callsMake autopatch calls

D.D. Talk to amateur radio operators in other Talk to amateur radio operators in other countriescountries


T7B07 T7B07 (pg 129)(pg 129)

What is Doppler shift?What is Doppler shift?A.A. A change in the satellite orbitA change in the satellite orbit

B.B. A mode where the satellite receives signals on one A mode where the satellite receives signals on one band and transmits on anotherband and transmits on another

C.C. A change in signal frequency caused by A change in signal frequency caused by motion through spacemotion through space

D.D. A special digital communications mode for some A special digital communications mode for some satellitessatellites


Doppler ShiftDoppler ShiftDoppler 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.


T7B11 T7B11 (pg 129)(pg 129)

What do the initials LEO tell you about an What do the initials LEO tell you about an amateur satellite?amateur satellite?A.A. The satellite battery is in Low Energy Operation The satellite battery is in Low Energy Operation

modemode

B.B. The satellite is performing a Lunar Ejection Orbit The satellite is performing a Lunar Ejection Orbit maneuvermaneuver

C.C. The satellite is in a Low Earth OrbitThe satellite is in a Low Earth OrbitD.D. The satellite uses Light Emitting OpticsThe satellite uses Light Emitting Optics


T7B04 T7B04 (pg 131)(pg 131)

Who may make contact with an astronaut on the Who may make contact with an astronaut on the International Space Station using amateur radio International Space Station using amateur radio frequencies?frequencies?A.A. Only members of amateur radio clubs at NASA Only members of amateur radio clubs at NASA

facilitiesfacilities

B.B. Any amateurAny amateur with a Technician or higher with a Technician or higher class licenseclass license

C.C. Only the astronaut's family members who are hamsOnly the astronaut's family members who are hams

D.D. You cannot talk to the ISS on amateur radio You cannot talk to the ISS on amateur radio frequenciesfrequencies

Presented by Heart Of Texas Amateur Radio Club (HOTARC)

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