Chapter 2 - Communications Flashcards
Direct communication
The straight line travel of radio signals between the transmitting radio and the receiving radio.
Repeated communications
Used to strengthen communication signals between radios, increase distance of transmission or increase capacity on the system.
Radio limitations
Distance, physical barriers, deadzones, interference, and ambient noise
ABCs
Be Accurate, Brief, and Concise.
DVRS Repeaters
A repeater integrated with a mobile radio control head that merges the primary tactical channel with the backup simplex channel.
Zones
CFD radio system is categorized into six zones (A, B, C, D, E, and F).
Channels
There are 16 channels per zone in the CFD radio system.
Tower Sites
Tower sites emit frequencies and aid in the sending and receiving of duplex radio communications. There are 8 tower sites strategically located around Calgary.
Radio Systems
Radio systems for the CFD consist of: mobile radios for vehicles, hand-held portable radio’s for fire crews and Digital Vehicle Repeater Systems (DVRS). Radio systems can operate in either duplex or simplex mode.
Duplex Mode (Trunking)
Radio communications are transmitted on one frequency and received on another. All duplex transmissions must reach a radio tower in order to rebroadcast back to other duplex users and/or dispatch.
1. Tactical
2. Utility
3. Training
4. Airport
5. Zone (dispatch) Channel
6. Technical Rescue.
7. Mutual Aid
Simplex Mode (Conventional)
Simplex transmissions are radio to radio and are sent and received on the same frequency. They are “line of sight” and have a limited transmission range local to the area around the incident and will not be heard throughout the city like on the duplex system. They can dramatically improve local site communications for incidents where the duplex system is not providing adequate coverage.
- Simplex channels are unable to reach radio towers, dispatch and duplex/tactical channels on their own. However, with DVRS in operation that can change.
Talk groups
Talk groups is an addressing system where a zone is paired with a channel. If Dispatch assigns an incident Zone C, Channel 7, fire crews communicate on talk group C7; where C7 is defined as a tactical channel.
Personnel tuning in to Zone E or Zone F on channels 1-12 can communicate on talk groups E 1-12 or F 1-12; where they are defined as simplex channels.
Dispatch Channels
Located within Zone B and Zone C of the radio system and use channels (B13-14 and C13-14). Used primarily for communication between Dispatch and apparatus officers.
- B13 north of Bow river
- C13 south of Bow river
Tactical Channels
Located within Zone B and Zone C of the radio system and use channels (B1-B9 and C1-C9).
Utility Channels
Located within Zone A of the radio system and use channels (A1-5). Typically they are for non-emergency use like inspections, hydrant testing, in station training, and community events.
Training Channels
Located within Zone A of the radio system and use channels (A7-A11).
Simplex Channels
Located within Zone E and Zone F of the radio system and use the same channels in correlation with tactical channels 1 – 12 (E1-E12 and F1-F12).
- Simplex channels allow crew members to communicate with each other directly through the line of sight. They are used as a backup when communication on duplex tactical channels start to deteriorate. All simplex channels will have male voice announcements to differentiate from the female voice announced on the duplex channel.
- Contact with Dispatch and EAB notification are possible, however, if a DVRS unit is present and tuned onto the corresponding assigned tactical/simplex channels. The
simplex user is capable of reaching the trunking system via the DVRS.
Portable radios
Portable radios have a unique encoded 6-digit identifier, which is displayed on the main and top LED screens as well as the attached label on the front. CFD 6-digit identifiers range from 760001 to 762000.
Portable Radio Swap
When a portable radio becomes damaged or inoperable, contact a District Chief for a replacement.
- Every radio swap requires updating the damaged radio and replacement radio aliases in the database. DC’s must ensure dispatch completes both.
- When a District Chief provides a replacement portable, it becomes the permanent radio for that “seat position”.
Staffing Limits
There are now staffing limits on apparatus to coincide with the number of assigned portable radios. There are 5 assigned radios per engine and 3 per secondary apparatus.
Riding Between Apparatus
The practice of (probationary firefighters, 3RD or 5TH firefighters) riding between 2 apparatus during a shift is no longer accepted in order to prevent misidentification in a Mayday situation.
Once original apparatus has been repaired, the temporary unit must be swapped back out.
True
Radio Failure
Crews should move to SIMPLEX when “SITE TRUNKING” is displayed as the radio system behaviour is no longer consistent.
Testing a Radio Signal
One- Bad (unreadable)
Two- Poor (readable now and then)
Three- Fair (readable, but with difficulty)-
Four- Good (readable)
Five- Excellent (perfectly readable)
IE- 5 x 5 is excellent clarity and volume; 2 x 5 is poor clarity and excellent volume.
Portable radio
The CFD uses the Motorola APX 6000 XE (Model 2.5) that is a hand-held portable radio used for communications on the fire ground or CFD business.
- It is submersible to 2 metres for 2 hours.
Remote Speaker Microphone (RSM)
Xtreme Temperature RSM Cable will withstand heat exposure of 500 ̊F (260 ̊C) for up to five minutes.
EAB
Emergency Activation Button
- Orange button located on the top of the RSM and portable radio. Pressing either button will activate the Emergency Alert Tone. This also activates the LED light on the RSM which will flash “SOS” in Morse code. Additionally, the top and front LED screens will flash orange and the word “Emergency” displays.
- The EAB is used by a firefighter in distress or by a radio user witnessing another firefighter in distress.
- On duplex, the EAB users radio itself will not emit a tone after depressing the EAB. It will, however, flash Orange on the LED screen and the RSM strobe light will flash.
- EAB user should still depress PTT to avoid being interrupted after 10 sec hot mic expires. PTT times out after 60 seconds.
Backlight and Bar Colour
Orange- Emergency alerts
Red- Critical alerts
Battery
When removing a battery ensure the radio is in the off position. When charging a battery attached to the radio, turn it off to ensure a full charge.
- Portable radio batteries are to be changed out at the start of every 24-hour shift or when the radio indicates the battery is running low on capacity (double chirp).
- Crews are instructed to carry one battery and have the second battery in a charger.
Best Practices
Wear radio mic on shoulder or high on chest.
Position radio mic 1-2” from the mouth and speak directly into it
Shield the RSM from background noise in high noise environments. Turn or move away.
SCBA (Voice amplifier position)
- RSM turned towards Voice Amplifier at a 45-degree angle, 2-3” away.
- User may need to elevate their voice or pitch while remaining clear for best results. Do not shout.
EAB Functions on Simplex without DVRS
- Due to simplex channels not reaching the trunking system, EAB notification is not sent to dispatch or corresponding tactical channels. However, other simplex users in close proximity should receive notifications.
- No hotmic on simplex with or without DVRS on scene
- No channel priority (will not interrupt an ongoing transmission). On simplex, the EAB user must wait for a break in radio transmissions to send a message.
- Unique loud audio chirp at the end of the simplex transmission, (heard by receiving radios that indicate the EAB user is on simplex).
- When an EAB is activated; if it is not immediately acknowledged by IC, then other radio users will have to ensure IC is notified. This step is critical during an EAB activation on stand-alone simplex, no DVRS on scene. Only the simplex users within the receive range of the radio transmitting the EAB alert will receive the alert notification along with the 6-digit identifier. These users must ensure that IC receives the EAB notification and identifier information. IC can then have dispatch manually search the dispatch registered radio database to identify the EAB user seat position.
Cancelling the Emergency Call
To cancel an emergency call, push and hold the EAB until a single long beep can be heard. This will indicate that the emergency has been cancelled. The intelligent lighting and the LED strobe will turn off. The display will read “Emergency Received” for several seconds until clearing from the screen.
- The portable radios have a new safety feature that prevents the radio from being accidentally turned off via the On/Off Control Knob after the EAB has been activated. To cancel an EAB, the user will no longer be able to turn the radio off to reset. The user MUST hold down the EAB until the long beep is heard. This will reset the individual radio but Dispatch will still need to reset the system. EAB cancellation is a 2-step process. IC should confirm both are completed.
There are 3 types of critical messages.
- Mayday
- Emergency Traffic
- Urgent Message
If the situation is critical but radio traffic is continuous, preventing access to initiate the alert tone, activate the orange EAB on your portable radio to grab priority and
proceed with your critical message.
True
Guidelines For Using Radios
- Declare who you are calling then identify yourself. For example, state “Dispatch, this is Engine 21.”
- Acknowledge a transmission as soon as possible by saying “go ahead”. If a message cannot be taken, simply say “standby”, or by stating your call sign.
- Roger and Affirmative. Understand the difference between Roger and Affirmative, the word “roger” indicates that you have received a message, “affirmative” is to be used if an answer is yes. As an example, E2 calls you and says, “Engine 1, Engine 2, confirm you are on-scene” your answer would be “Engine 1, affirmative”. Should you hear the following “Engine 1, Engine 2, bring your tags to Command” your answer would be “Engine 1, roger”.
Continued…
- Read Backs. Should you be tasked over the radio, read back the assignment, for example, “Engine 1. Operations. You will be my Vent team. Vent from Alpha to Delta”. Your answer “Roger, Engine 1 is now Vent Team and will be venting from Alpha to Delta”.
- Avoid complex codes and slang. Use plain English. Avoid words that are difficult to distinguish and hear, such as “yes” and “no”. Instead, use “affirmative” and “negative”. Don’t use slang such as, “OK”, “ten-four”, “over-and-out”, “breaker-breaker”, “oakey- dokey”, etc. Don’t replace “Roger” with “Copy”.
- Avoid saying “please” and “thank you”. Courtesy is assumed and wastes airtime.
- Remember – Non-CFD persons and media have the ability to scan all our radio frequencies (including TAC channels) so it is important to remain professional in all transmissions.
Articulation of the Phonetic Alphabet
LETTER WORD PRONOUNCED
A Alpha AL FAH
B Bravo BRAH VOH
C Charlie CHAR LEE
D Delta DELL TAH
E Echo ECK OH
F Foxtrot FOKS TROT
G Golf GOLF
H Hotel HOH TELL
I India IN DEE AH
J Juliett JEW LEE ETT
K Kilo KEY LOH
L Lima LEE MAH
M Mike MIKE
N November NO VEM BER
O Oscar OSS CAH
P Papa PAH PAH
Q Quebec KEH BECK
R Romeo ROW ME OH
S Sierra SEE AIR RAH
T Tango TANG GO
U Uniform YOU NEE FORM
V Victor VIK TAH
W Whiskey WISS KEY
X X-Ray ECKS RAY
Y Yankee YANG KEY
Z Zulu ZOO LOO
Articulation of Numbers
0
ZE-RO
5
FIFE
1
WUN
6
SIX
2
TOO
7
SEV-en
3
TREE
8
AIT
4
FOW-er
9
NINE-er
Numbers
“One-digit” numbers are given with the word “number” preceding the number. For example, 5 Main Street is stated: Number 5 Main Street.
* “Two-digit” numbers are preferably stated as individual numbers. For example, 14 Cedar Avenue would be one-four Cedar Avenue.
* “Three-digit” numbers are preferably stated as individual numbers. For example, 512 is five-one-two.
* “Four digits” are stated as individual numbers or in twos, but not in threes. For example, 1412 is one-four-one-two.
* “Five digits” are stated in threes and twos. For example, 12453 is one, two, four (pause) five, three.
* An exception exists for exact thousands, which are transmitted by pronouncing each digit followed by the word “thousand.”
Digital Vehicle Repeater System (DVRS)
The only function of DVRS is to bridge or connect the tactical channel with the corresponding backup simplex channel.
Tones
-Long Low - Pitched Tone Out of Range
-Series of Medium Pitched Tones Site Trunking
-Bonk sound Channel Not Available
