Communications Training for Amateur Radio Operators Introduction to the San Diego County 800 MHz RCS System & Local Government VHF Systems

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Communications Training for Amateur Radio
OperatorsIntroduction to the San Diego County
800 MHz RCS System Local Government VHF Systems

• Craig Williams W6CAW
• Support 46

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We will Cover Today

• A general introduction to 2-way radio
  communications systems.
• Specifics of the San Diego County 800 MHz,
  Regional Communications Systems (RCS) why it
  works like your cell phone.
• Specifics on Very High Frequency (VHF)
  Communications Systems, Cal Fire, USFS, OES why
  they work like your Ham Radios.

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RADIO SPECTRUM REFERS TO THE ARRAY OF CHANNELS
or FREQUENCIES AVAILABLE FOR COMMUNICATIONS
What is Radio Spectrum?...
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Topology of 2-way Communications

• Simplex, AKA direct or talk-around. Your
  transmit and receive frequencies are the same.
  You do not go through a repeater.
• Example on VHF, Cal Fire TAC 5 on RCS, CNV CAR1.
  Ham simplex 146.52
• Repeater. - Your transmit and receive frequencies
  are different and are routed through a mountain
  top radio system. The norm for all RCS 800 and
  most VHF Command and Dispatch frequencies.
• Example on RCS, CFMVD10A on VHF Monta Vista
  Dispatch, Tone 5. Ham repeaters.

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Tower Overview, County RCS

• A typical RCS tower in the back country has 13
  channels.
• 1-Control Channel
• 11-Voice Channels
• Here F1 is the Control Channel and F2 is the
  Voice Channel

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RCS Voice Channel Assignment

• When an 800 radio is keyed up the Central
  Controller, through the Control Channel, assigns
  you a voice channel.
• All other radios using the same Talkgroup, ie.
  CMD 10A, in the area of the same tower, will then
  use the same voice channel.

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Typical East Loop 800 Site

• This slide represents four Agencies using a four
  channel 800 Site.

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800 Radios
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RCS 800 Upgrades

• ALL San Diego County 800 users, over 30,000 of
  them, can use the same tower. Thats Local Fire,
  SDSO, Cal Fire, USFS, Rural Bus, Public Works,
  and AMR (Medical), just to name some of the
  normal local users in a rural area.
• With only 11 discrete voice channels not everyone
  may be able talk at the same time. ( Know your
  800 Beep Codes like the Busy Beep.)
• Since the October 2003 fires the East (county)
  Loop has been upgraded. This gave us additional
  voice channels and the capability to fully
  integrate with the North, South and North East
  loops. A few Intelli-Repeaters in the North East
  county area are still limited to 3 or 4 voice
  channels

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800 Talkgroup Types

• Dispatch - Talkgroup designated for the routine
  and emergency dispatch communications for the
  designated agency.
• Hailing ( County Call ) - Talkgroup designated
  for a person from one agency to contact any
  person from the same or another agency or
  Dispatch Center. Once contact is made, the
  conversation should be switched to an available
  tactical talkgroup.
• Fire Command talkgroups are used by fire agencies
  for command and control communications while
  conducting operations. Only the Incident
  Commander (IC) normally uses the Command
  Talkgroup.
• Tactical - Talkgroup designed to hold
  conversations, or conduct tactical operations
  between responders and between responders and
  their IC.

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San Diego County RCS
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Typical RCS Fleet Map
Every agency has a dedicated Fleet Map of
channels. In 2009 all fire agencies in San
Diego County were re-programmed to the same Fleet
Map.
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• The 800 radio system's central computer is
  located at the County's Operation Center off of
  Clairemont Mesa Boulevard and Hwy 15. Typically,
  the computer processes calls between dispatch and
  the field units through a network of microwaves
  and mountain top repeaters. But, occasionally a
  mountain top repeater and the computer lose
  contact with one another. When this occurs,
  individual repeater sites begins to process calls
  on their own hence, the name Site Trunking.
• Site Trunking is a back up mode that maintains
  site communications without disrupting the rest
  of the zone. So, Transmissions at the site are
  only re-broadcast at that site, and transmissions
  at other sites are not re-broadcast at the site
  in Site Trunking.
• If this occurs, you may not be able to contact
  your dispatcher (or other units if they are not
  affiliated with the same mountain top repeater).
  To reestablish a connection with the central
  computer, you may need to do one or both of the
  following
• (1) change locations until your radio affiliates
  with another mountain top repeater,
• (2) force your radio to affiliate with another
  mountain top repeater by pressing and holding the
  side button on your radio.
• IMPORTANT If a 800 site goes completely off the
  air you will only be able to communicate locally
  on one of the conventional channels. Ie. CARS1

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Typical VHF System

• Only one frequency per channel/repeater.
• Manual control of towers from the Dispatch
  Center.
• May go through Repeater (green signal) or Direct
  (red signal)
• May be voted. Many sites receive but only one
  transmits.
• You need to select the proper Tone to talk to
  the dispatcher!

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VHF Sites in the Campo Area
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VHF Radio Procedures

• The normal operational channel assignments for
  the VHF systems generally match the assignments
  on the RCS 800 System.
• Dispatch - Frequency designated for the routine
  and emergency Dispatch communications for the
  designated agency. A geographic area is normally
  associated with a mountain top repeater and a PL
  tone closest to the agency being dispatched. IE.
  Monta Vista Dispatch, Tone 5, Tecate Peak,
  closest mountain top to Campo.
• Command - Frequency designated as an Incident
  Command Channel as described under the Incident
  Command System (ICS) and or the National Incident
  Management System (NIMS). Other Incident Command
  Frequencies may be assigned for use by other ICS
  elements such as, Air Operations, Logistics,
  Communications, Finance, ect..
• Fire Command channels are used by fire agencies
  for incident command and control communications
  while conducting operations. IE command 2, Tone
  3. Normally only the Incident Commander (IC)
  should be using the Command Channel!
• Tactical Usually a direct, non-repeated
  frequency. Frequency designed to hold
  conversations between personnel at an incident
  site, or to conduct local tactical operations.
  Examples. All the fire personnel at a vehicle
  fire. All personnel assigned to a Branch of a
  major incident. No tones are used on TAC
  channels.

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NOTE Yellow print indicates San Diego County
coverage
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VHF Radios
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Summary

• Review the differences between 800 Trunking and
  VHF repeater systems.
• Review your Communications Manual. There is one
  in each vehicle and one in the Station.

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Where to Get More Information

• www.campofire.org
• Select the Bulletins button

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Finally, about modulation

• ALL public service radios employ close talk
  microphones to reduce unwanted background noise.
  This means, if you dont hold the radio or
  microphone close to your mouth no one will hear
  you!
• Ham radio mikes come in all flavors. Get to know
  yours!

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Questions?