Technician Licensing Class “Chapter 5”

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

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

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

4. Transmitters and Receivers • 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. HF 160 1.8 MHz 80 3.5 MHz 60* 5 Mhz 40 7 MHz 30 10 Mhz 20 14 Mhz 17 18 Mhz 15 21 Mhz 12 24 Mhz 10 28 Mhz VHF 6 50 Mhz 2 144 Mhz 1¼ 222 Mhz UHF 70 cm 440 Mhz 33 cm 902 Mhz 23 cm 1240 Mhz 13 cm 2300 Mhz Amateur Radio Bands

6. Control and Function Keys • Can be separate or same key • 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 radio’s operation

7. Transmitters and Receivers • Transmitter Functions

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

9. Transmitter Functions • Spurious Signals • Turn down microphone gain • Turn down compressor/speech processor • Back away from microphone • ALC • Proper Tuning if not solid state equipment

10. Transmitter Functions • Microphones • Hand • Desk • Boom • Headset • Throat • VOX vs Manual

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

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

13. Modern Transceiver

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

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

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

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

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

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

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

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

22. T8D:Non-voice communications; image data, digital modes CW, packet, PSK31 T8D7 PSK31 is a low-rate data transmission mode. 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. You can connect a PSK-31 and RTTY data reader to your radio to decode messages

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

24. APRS

25. APRS – www.findu.com

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

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

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

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

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

31. T8C11 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

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

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

34. T8D06 What does the abbreviation PSK mean? • Pulse Shift Keying • Phase Shift Keying • Packet Short Keying • Phased Slide Keying

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

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

37. POWER SUPPLIES & BATTERIES

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

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

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. Slow-Blow fuse Automobile fuse Fuses Place the fuses as close to the battery as possible

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

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

43. T4A10 What is the source of a high-pitched whine that varies with engine speed in a mobile transceiver’s receive audio? • The ignition system • The alternator • The electric fuel pump • Anti-lock braking system controllers

44. T4A11 Where should a mobile transceiver’s power negative connection be made? • At the battery or engine block ground strap • At the antenna mount • To any metal part of the vehicle • Through the transceiver’s mounting bracket

45. T5A06 How much voltage does a mobile transceiver usually require? • About 12 volts • About 30 volts • About 120 volts • About 240 volts

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

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

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

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

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