2013 Week 5: Amateur Radio Equipment

This is the class outline for week 5 of the SCARS Technician class 2013.

Week 5 Outline

Transmitters and Receivers

  • “By the end of this chapter, you’ll know your way around common radio controls and their functions.”
  • “Your radio will be different, of course, so rely on the owner’s manual for complete information.”
  • “…downloading user’s manuals from the manufacturer’s Web sites.”

Selecting band, frequency, and mode

Icom IC-718 HF radio. Currently (Feb 2013) sells for about $750.

Control and Function keys

RF gain, Mic (gain)

Over-modulation, over-deviation

Microphone types, plugs

Code keys

Receiver functions

  • AF gain (volume)
  • RF gain
  • attenuator\
  • pre-amp
  • AGC – autmatic gain control – fast or slow
  • squelch
  • band-pass filters
    • IF or audio
    • SSB: 2.4 kHz
    • Morse code, data: 500 Hz or less
    • FCC Narrow-Band Mandate
    • Norman Public Schools to purchase radios
    • Wikipedia:16 kHz wide signals with 5 kHz deviation is normal in this band. 8 kHz narrow signals with 2.5 kHz deviation can also be found.

Handheld Transceivers “HTs”

  • Dual band, usually 2 m and 70 cm (440)
  • often wide-band receive
  • make decent mobile rig with:
    • DC cord
    • speaker-mic
    • external (e.g., mag-mount) antenna

    Digital Communications

    • modem, TNC, MPC, PC sound card
    • error correction <li
      • CW
      • RTTY
      • Winlink
      • PSK31 or MFSK
      • packet radio
      • DSTAR (new Norman repeater, W5TC)
      • APRS

      </li

    Setting up for digital modes

    Gateways

    Power Supplies and Batteries

    Mobile Power Wiring

    Generators and Inverters

    Batteries

    RF Interference (RFI)

    Filters

    Band-pass filters can be added to equipment to block harmonics and other spurious emissions.

    Overload

    • Why hams “interfere with” TV or broadcast radio
    • To save money, TVs not equipped with ability to reject a strong signal on a nearby frequency
    • Filter can be added at TV input to correct problem

    Harmonics and Spurious Emissions

    Low pass filter can be added to HF rig to minimize possibility of interfering with commercial frequencies (TV, FM radio)

    Noise Sources

    See page 5-21 of book!

    Unknown Signals

    Radio Direction Finding, Fox Hunting

    Guidelines

    Part 15 Rules

    Grounding