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Technician Licensing Class Chapter 5 Valid dates: July 1, 2010 – June 30, 2014 Amateur Radio Equipment.

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Presentation on theme: "Technician Licensing Class Chapter 5 Valid dates: July 1, 2010 – June 30, 2014 Amateur Radio Equipment."— Presentation transcript:

1 Technician Licensing Class Chapter 5 Valid dates: July 1, 2010 – June 30, 2014 Amateur Radio Equipment

2 2 Chapter 5 Contents Transmitters and Receivers Transmitters and Receivers Digital Communications Digital Communications Power Supplies and Batteries Power Supplies and Batteries Radio Frequency Interference (RFI) Radio Frequency Interference (RFI) RF Grounding RF Grounding

3 3 Transmitters and Receivers Used to be separate units Used to be separate units Still can be Still can be Transceivers (containing both transmitter and receiver more common place now) Transceivers (containing both transmitter and receiver more common place now) Abbreviations Abbreviations Tx Rx or Rcvr XCVRTx Rx or Rcvr XCVR

4 4 Transmitters and Receivers Selecting Band, Frequency and Mode Selecting Band, Frequency and Mode Amateur radio has bands rather than channels other than on 60 meters) AM and SSB can be more than speech (CW data FM can be voice or data

5 5 Amateur Radio Bands HF HF MHz MHz MHz803.5 MHz 60*5 Mhz60*5 Mhz 407 MHz407 MHz 3010 Mhz3010 Mhz 2014 Mhz2014 Mhz 1718 Mhz1718 Mhz 1521 Mhz1521 Mhz 1224 Mhz1224 Mhz 1028 Mhz1028 Mhz VHF VHF 650 Mhz 2144 Mhz 1¼222 Mhz UHF UHF 70 cm440 Mhz 33 cm902 Mhz 23 cm1240 Mhz 13 cm2300 Mhz

6 6 Control and Function Keys Can be separate or same key Can be separate or same key Control keys typically directly control the radio Control keys typically directly control the radio Function keys are more like menu and are used to select and set functions and parameters for the radios operation Function keys are more like menu and are used to select and set functions and parameters for the radios operation

7 7 Transmitters and Receivers Transmitter Functions Transmitter Functions

8 8 Transmitter Functions RF Power Control RF Power Control Microphone Gain Microphone Gain Speech Compressor/Processor Speech Compressor/Processor PEP (Peak Envelope Power) SSB & AM PEP (Peak Envelope Power) SSB & AM ALC ALC Band and frequency tuning Band and frequency tuning

9 9 Transmitter Functions Spurious Signals Spurious Signals Turn down microphone gainTurn down microphone gain Turn down compressor/speech processorTurn down compressor/speech processor Back away from microphoneBack away from microphone ALCALC Proper Tuning if not solid state equipmentProper Tuning if not solid state equipment

10 10 Transmitter Functions Microphones Microphones HandHand DeskDesk BoomBoom HeadsetHeadset ThroatThroat VOX vs Manual VOX vs Manual

11 11 Transmitter Functions Keys Keys ManualManual Straight Key Straight Key Semi-AutomaticSemi-Automatic Bug Dits automatic Dahs automatic Bug Dits automatic Dahs automatic Automatic/ElectronicAutomatic/Electronic Dits and Dahs both automatic and self completing Dits and Dahs both automatic and self completing Single and double lever types Single and double lever types Iambic and non iambic Iambic and non iambic

12 12 Receiver Functions AF and RF Gain AF and RF Gain Bandwidth (filters) Bandwidth (filters) Band and frequency tuning Band and frequency tuning Attenuator Attenuator DSP DSP Automatic Gain Control (AGC) Automatic Gain Control (AGC) RIT Receiver Incremental Tuning (Clarifier) RIT Receiver Incremental Tuning (Clarifier) Allows rx tuning off of tx frequency in xcvrAllows rx tuning off of tx frequency in xcvr

13 13 Modern Transceiver

14 14 Digital Signal Processing (DSP) Noise Reduction Noise Reduction Variable signal filtering Variable signal filtering Automatic notching filtering Automatic notching filtering Audio contouring on tx and rx Audio contouring on tx and rx Shift Shift Width Width

15 15 Handheld Tranceivers Single Band, Dual, Tri, and quad band Single Band, Dual, Tri, and quad band Built in microphone and speakers but jacks for external Built in microphone and speakers but jacks for external Memories Memories Push to Talk PTT Push to Talk PTT Rubber Duck antenna Rubber Duck antenna Better antennas Better antennas Connect to outside antennas Connect to outside antennas

16 16 DIGITAL COMMUNICATIONS Need Modem / TNC Need Modem / TNC Advantages Digital Signal Processing Advantages Digital Signal Processing Redundancy Redundancy Error Correction Error Correction Allow easy reception of very weak signals Allow easy reception of very weak signals

17 17 Amateur Digital Modes RTTY RTTY PACTOR & WINMOR PACTOR & WINMOR PSK31 & MFSK PSK31 & MFSK Olivia Olivia Domino Domino VHF & UHF Packet and Winlink 2000 VHF & UHF Packet and Winlink 2000

18 18 Errors in Digital Data Errors measured in Bit Error Rate (BER) Errors measured in Bit Error Rate (BER) Parity bits Parity bits Forward Error Correction Forward Error Correction

19 19 Packet & Packet Networks Use FSK (Frequency Shift Keying) Use FSK (Frequency Shift Keying) Can run automatically Can run automatically ARQ Automatic Repeat Request ARQ Automatic Repeat Request AX.25 protocol AX.25 protocol Bulletin Boards Bulletin Boards Messages Messages Or direct hands on communications Or direct hands on communications Think long lists of data to be transmitted Think long lists of data to be transmitted

20 20 T8D: Non-voice communications; image data, digital modes CW, packet,PSK31 T8D8 Packet transmissions may include:T8D8 Packet transmissions may include: A check sum which permits error detection; A check sum which permits error detection; A header which contains the call sign of the station to which the information is being sent; A header which contains the call sign of the station to which the information is being sent; Automatic repeat request in case of error. Automatic repeat request in case of error. Laptop, TNC, and Handheld comprise Packet Station.

21 21 Keyboard-to-Keyboard Most Digital Modes including RTTY and CW Most Digital Modes including RTTY and CW CW faster than you can send or receive CW faster than you can send or receive PSK31, Olivia, Domino, Many others PSK31, Olivia, Domino, Many others

22 22 T8D: Non-voice communications; image data, digital modes CW, packet, PSK31 T8D7 PSK31 is a low-rate data transmission mode.T8D7 PSK31 is a low-rate data transmission mode. PSK-31 transmission rate is about normal typing speed. PSK-31 transmission rate is about normal typing speed. PSK is a remarkable digital mode that slices through interference and gets message across sometimes to the moon and back. PSK is a remarkable digital mode that slices through interference and gets message across sometimes to the moon and back. You can connect a PSK-31 and RTTY data reader to your radio to decode messages

23 23 APRS Automatic Position Reporting System Automatic Position Reporting System /www.ui-view.org/findu.htm /www.ui-view.org/findu.htm

24 24 APRS

25 25 APRS –

26 26 Winlink Permits sending over the air on HF, VHF or UHF Permits sending over the air on HF, VHF or UHF

27 27 Setting up for digital modes Page 5-12 of Manual Page 5-12 of Manual Transceiver connects to Transceiver connects to PC, audio interface, and TNCPC, audio interface, and TNC

28 28 Gateways PAGE 5-12 PAGE 5-12 Usually forward messages Usually forward messages Some provide Internet Connectivity Some provide Internet Connectivity

29 29 T4A06 Which of the following would be connected between a transceiver and computer in a packet radio station? A.Transmatch B.Mixer C.Terminal node controller D.Antenna

30 30 T4A07 How is the computers sound card used when conducting digital communications using a computer? A.The sound card communicates between the computer CPU and the video display B.The sound card records the audio frequency for video display C.The sound card provides audio to the microphone input and converts received audio to digital form D.All of these choices are correct

31 31 T8C11 What name is given to an amateur radio station that is used to connect other amateur stations to the Internet? A.A gateway B.A repeater C.A digipeater D.A beacon

32 32 T8D02 What does the term APRS mean? A.Automatic Position Reporting System B.Associated Public Radio Station C.Auto Planning Radio Set-up D.Advanced Polar Radio System

33 33 T8D03 Which of the following is normally used when sending automatic location reports via amateur radio? A.A connection to the vehicle speedometer B.A WWV receiver C.A connection to a broadcast FM sub- carrier receiver D.A Global Positioning System receiver

34 34 T8D06 What does the abbreviation PSK mean? A.Pulse Shift Keying B.Phase Shift Keying C.Packet Short Keying D.Phased Slide Keying

35 35 T8D07 What is PSK31? A.A high-rate data transmission mode B.A method of reducing noise interference to FM signals C.A method of compressing digital television signal D.A low-rate data transmission mode

36 36 T8D08 Which of the following may be included in packet transmissions? A.A check sum which permits error detection B.A header which contains the call sign of the station to which the information is being sent C.Automatic repeat request in case of error D.All of these choices are correct

37 37 POWER SUPPLIES & BATTERIES

38 38 Power Supplies Convert AC current to voltages needed by equipment Convert AC current to voltages needed by equipment Can be internal or external Can be internal or external Wall warts Wall warts Power Supplies Power Supplies Analog or LinearAnalog or Linear SwitchingSwitching Regulated to keep voltage constant with and without loadRegulated to keep voltage constant with and without load Rating must be at least as much as required by the equipment

39 39 Mobile Power Wiring Fuse both Positive and Negative Leads Fuse both Positive and Negative Leads Connect negative lead to battery terminal Connect negative lead to battery terminal Use grommets when wire passes through bulkhead or firewall Use grommets when wire passes through bulkhead or firewall Do not assume all metal is grounded. Lots are connected with plastic Do not assume all metal is grounded. Lots are connected with plastic Keep leads short and use heavy cable Keep leads short and use heavy cable Alternator whine can be removed with DC power filter at your radio Alternator whine can be removed with DC power filter at your radio

40 40 T0A: AC power circuits; hazardous voltages, fuses and circuit breakers, grounding, lightning protection, battery safety, electrical code compliance. T0A4 The purpose of a fuse in an electrical circuit is to interrupt power in case of overload.T0A4 The purpose of a fuse in an electrical circuit is to interrupt power in case of overload. Place the fuses as close to the battery as possible Fuses Slow-Blow fuse Automobile fuse

41 41 Generators & Inverters Generate power – usually 120 0r 240 VAC Generate power – usually 120 0r 240 VAC Inverters – Turn DC power into AC power Inverters – Turn DC power into AC power Voltage regulation very important to protect equipment from surges Voltage regulation very important to protect equipment from surges

42 42 T4A03 Which is a good reason to use a regulated power supply for communications equipment? A.It prevents voltage fluctuations from reaching sensitive circuits B.A regulated power supply has FCC approval C.A fuse or circuit breaker regulates the power D.Power consumption is independent of load

43 43 T4A10 What is the source of a high-pitched whine that varies with engine speed in a mobile transceivers receive audio? A.The ignition system B.The alternator C.The electric fuel pump D.Anti-lock braking system controllers

44 44 T4A11 Where should a mobile transceivers power negative connection be made? A.At the battery or engine block ground strap B.At the antenna mount C.To any metal part of the vehicle D.Through the transceivers mounting bracket

45 45 T5A06 How much voltage does a mobile transceiver usually require? A.About 12 volts B.About 30 volts C.About 120 volts D.About 240 volts

46 46 T6D05 What type of circuit controls the amount of voltage from a power supply? A.Regulator B.Oscillator C.Filter D.Phase inverter

47 47 T7B09 What could be happening if another operator reports a variable high- pitched whine on the audio from your mobile transmitter? A.Your microphone is picking up noise from an open window B.You have the volume on your receiver set too high C.You need to adjust your squelch control D.Noise on the vehicles electrical system is being transmitted along with your speech audio

48 48 Batteries Disposable Disposable Used once and disposed of cannot be rechargedUsed once and disposed of cannot be recharged Rechargeable or Secondary Rechargeable or Secondary Chemical reaction reversed to chargeChemical reaction reversed to charge Storage Storage Also rechargeable used for long-term energy storageAlso rechargeable used for long-term energy storage

49 49 Handheld Radio Batteries Some radios can use disposable batteries Some radios can use disposable batteries Most use custom packs of rechargeables Most use custom packs of rechargeables NiCad (Nickel Cadmium)NiCad (Nickel Cadmium) NiMH (Nickel-metal hydride)NiMH (Nickel-metal hydride) Li-ion (Lithium Ion)Li-ion (Lithium Ion) Li-ion highest energy capacity NiMH and NiCad next. Li-ion highest energy capacity NiMH and NiCad next. Most HTs come with chargers to charge batteries Most HTs come with chargers to charge batteries Memory in NiCad batteries Memory in NiCad batteries

50 50 T6A10 What is the nominal voltage of a fully charged nickel-cadmium cell? A.1.0 volts B.1.2 volts C.1.5 volts D.2.2 volts

51 51 T6A11 Which battery type is not rechargeable? A. Nickel-cadmium B. Carbon-zinc C. Lead-acid D. Lithium-ion

52 52 T0A08 What is one way to recharge a 12-volt lead-acid station battery if the commercial power is out? A.Cool the battery in ice for several hours B.Add acid to the battery C.Connect the battery to a car's battery and run the engine D.All of these choices are correct

53 53 T0A09 What kind of hazard is presented by a conventional 12-volt storage battery? A.It emits ozone which can be harmful to the atmosphere B.Shock hazard due to high voltage C.Explosive gas can collect if not properly vented D.All of these choices are correct

54 54 T0A10 What can happen if a lead-acid storage battery is charged or discharged too quickly? A.The battery could overheat and give off flammable gas or explode B.The voltage can become reversed C.The memory effect will reduce the capacity of the battery D.All of these choices are correct

55 55 RADIO FREQUENCY INTERFERENCE (RFI) Getting more common place Getting more common place Can be amateur radio interfering with other devices Can be amateur radio interfering with other devices OR OR Other devices interfering with amateur radio operation Other devices interfering with amateur radio operation

56 56 Filters Very important and useful in resolving Radio Frequency Interference Very important and useful in resolving Radio Frequency Interference AC power line filters AC power line filters RF choke/common-mode ferrite filters RF choke/common-mode ferrite filters

57 57 Direct Detection RF gets into devices and is turned into voltages that cause interference RF gets into devices and is turned into voltages that cause interference Common with phones Common with phones Low pass filter at wired phones modular jack Low pass filter at wired phones modular jack Chokes and ferrite on speaker cords Chokes and ferrite on speaker cords

58 58 Overload Fundamental Overload Fundamental Overload Strong signal just gets in and interferes with electronics because of its strengthStrong signal just gets in and interferes with electronics because of its strength High Pass Filter at Receiver High Pass Filter at Receiver Ferrite on devices power cord Ferrite on devices power cord Shielding at Receiver Shielding at Receiver If tx & rx frequencies close – notch filter or resolution not possible If tx & rx frequencies close – notch filter or resolution not possible

59 59 Harmonics & Spurious Emissions Low Pass Filters on Transmitter Low Pass Filters on Transmitter Can be in-band interference and cannot be filtered out at receiver Can be in-band interference and cannot be filtered out at receiver

60 60 Noise Sources Electrical equipment, lights, switches Electrical equipment, lights, switches Cracked or dirty insulators Cracked or dirty insulators Ignition noise from engines Ignition noise from engines Alternator whine Alternator whine Switching Power Supplies Switching Power Supplies Computer, peripheral & network equipment Computer, peripheral & network equipment

61 61 Unknown Signals Track with a radio when possible Track with a radio when possible Radio Direction Finding (RDF) Radio Direction Finding (RDF) TriangulationTriangulation Get azimuth bearing from three or more locationsGet azimuth bearing from three or more locations Plot on mapPlot on map Interference where lines crossInterference where lines cross

62 62 Guidelines Make sure your station is in good working order Make sure your station is in good working order Make sure you do not interfere with anything in your home Make sure you do not interfere with anything in your home Take care of any devices in your home that cause interference Take care of any devices in your home that cause interference

63 63 Guidelines Be diplomatic and good neighbor Be diplomatic and good neighbor Put yourself in the other persons position Put yourself in the other persons position Demonstrate where possible Demonstrate where possible Get help from other hams Get help from other hams

64 64 FCC Part 15 Rules FCC sanctioned unlicensed operation of certain low powered devices FCC sanctioned unlicensed operation of certain low powered devices NIB to licensed services NIB to licensed services Must accept interference from licensed services and other Part 15 devices Must accept interference from licensed services and other Part 15 devices

65 65 T7B: Common transmitter and receiver problems; symptoms of overload and overdrive, distortion, interference, over and under modulation, RF feedback, off frequency signals; fading and noise; problems with digital communications interfaces T7B8 If a "Part 15" device in your neighbors home is causing harmful interference to your amateur station:T7B8 If a "Part 15" device in your neighbors home is causing harmful interference to your amateur station: Work with your neighbor to identify the offending device; Work with your neighbor to identify the offending device; Politely inform your neighbor about the rules that require him to stop using the device if it causes interference; Politely inform your neighbor about the rules that require him to stop using the device if it causes interference; Check your station and make sure it meets the standards of good amateur practice. Check your station and make sure it meets the standards of good amateur practice. A simple snap-on choke filter like this one can help resolve harmful interference problems on Part 15 devices.

66 66 T4A04 Where must a filter be installed to reduce harmonic emissions? A.Between the transmitter and the antenna B.Between the receiver and the transmitter C.At the station power supply D.At the microphone

67 67 T4A05 What type of filter should be connected to a TV receiver as the first step in trying to prevent RF overload from a nearby 2 meter transmitter? A.Low-pass filter B.High-pass filter C.Band-pass filter D.Band-reject filter

68 68 T4A09 Which would you use to reduce RF current flowing on the shield of an audio cable? A.Band-pass filter B.Low-pass filter C.Preamplifier D.Ferrite choke

69 69 T7B02 What is meant by fundamental overload in reference to a receiver? A.Too much voltage from the power supply B.Too much current from the power supply C.Interference caused by very strong signals D.Interference caused by turning the volume up too high

70 70 T7B03 Which of the following may be a cause of radio frequency interference? A.Fundamental overload B.Harmonics C.Spurious emissions D.All of these choices are correct

71 71 T7B04 What is the most likely cause of interference to a non-cordless telephone from a nearby transmitter? A.Harmonics from the transmitter B.The telephone is inadvertently acting as a radio receiver C.Poor station grounding D.Improper transmitter adjustment

72 72 T7B05 What is a logical first step when attempting to cure a radio frequency interference problem in a nearby telephone? A.Install a low-pass filter at the transmitter B.Install a high-pass filter at the transmitter C.Install an RF filter at the telephone D.Improve station grounding

73 73 T7B06 What should you do first if someone tells you that your stations transmissions are interfering with their radio or TV reception? A.Make sure that your station is functioning properly and that it does not cause interference to your own television B.Immediately turn off your transmitter and contact the nearest FCC office for assistance C.Tell them that your license gives you the right to transmit and nothing can be done to reduce the interference D.Continue operating normally because your equipment cannot possibly cause any interference

74 74 T7B07 Which of the following may be useful in correcting a radio frequency interference problem? A.Snap-on ferrite chokes B.Low-pass and high-pass filters C.band-reject and band-pass filters D.All of these choices are correct

75 75 T7B08 What should you do if a "Part 15" device in your neighbors home is causing harmful interference to your amateur station? A.Work with your neighbor to identify the offending device B.Politely inform your neighbor about the rules that require him to stop using the device if it causes interference C.Check your station and make sure it meets the standards of good amateur practice D.All of these choices are correct

76 76 RF GROUNDING Electrical and RF ground not always same Electrical and RF ground not always same Use short lengths of heavy cable or flat strap to ground all equipment to ground rod Use short lengths of heavy cable or flat strap to ground all equipment to ground rod Flat Strap Is Best Flat Strap Is Best

77 77 RF GROUNDING Bad RF ground can result in RF current affecting sensitive audio or other equipment Bad RF ground can result in RF current affecting sensitive audio or other equipment Can cause shock or RF burns Can cause shock or RF burns RF feedback via microphone cable can distort your signal RF feedback via microphone cable can distort your signal

78 78 RF GROUNDING

79 79 T4A08 Which type of conductor is best to use for RF grounding? A.Round stranded wire B.Round copper-clad steel wire C.Twisted-pair cable D.Flat strap

80 80 T7B11 What is a symptom of RF feedback in a transmitter or transceiver? A.Excessive SWR at the antenna connection B.The transmitter will not stay on the desired frequency C.Reports of garbled, distorted, or unintelligible transmissions D.Frequent blowing of power supply fuses


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