Packet Radio Communications Plan
When and how to communicate by packet radio during an emergency
Background
Experience has shown that, in the event of a disaster, communications capabilities are in great demand. All available telephone lines and cell phone circuits will be heavily loaded. Fire and Police radio nets will be heavily loaded.
Part of the mission of the Burbank Fire Department Community Disaster Volunteer (CDV) program is to provide auxiliary communications in the event of a disaster. Packet Radio is part of these auxiliary communications.
This is an overview of Burbank CDV's packet radio communications plan. It discusses:
- CDV Potential Packet Radio Capabilities
- Packet Radio Operation
- Packet Radio Identification
- Packet Radio Frequencies
CDV Potential Packet Radio Capabilities
To help us accomplish our mission, the Burbank CDV program provides for the use of Packet Radio for four different situations. They are:
- Reliable error free information in text format when normal electrical power is out
- Reliable error free information in text format when cell phones and land line phones are heavily loaded
- Emergency NTS (National Traffic System) message information both for outgoing and incoming transmissions
- A message board similar to e-mail is available when the internet is not available
Reliable error free information in text format when normal electrical power is out
Often times in a major emergency such as earthquake, flood, fire, etc., all or part of the electric power grid is lost for some amount of time either in the local community or in other parts of the county. The BEARS' packet radio is not immediately dependent on the power grid, and also can be portable if the need arises. The packet format is error free by the nature of the transmission method.
The main packet radio unit for the BEARS will attached to a deep cycle marine battery (at the EOC) with a rating of at least 100 Amp Hours. This battery is attached to a trickle charge battery charger. When standard 110V AC is available the battery stays charged. When the power is lost, the packet system will transmit and receive for a minimum of 24 hours on battery power. Packet radio is a low power system. It does not have a long duty cycle and as such uses little battery power even at 100 W. An alternative to this can be an "instant-on" backup generator, which will serve the same purpose.
If the need arises, the whole system can be attached to a car battery, or the whole system can be transported elsewhere. In addition, there will be other Packet Radio units that BEARS members will take to remote locations such as shelters, or hospitals that can communicate to the main unit. If the main unit should fail, any of the other units can take over as the main unit from any location.
The transmission by the nature of the packet protocol (which is very similar to TCP/IP) is error free. When the packet TNC is connected to another packet TNC through the radios it will keep checking that all data was received without error. If there is an error, it will send again and again until there is no error. If the radio connection is lost, the unit will alert that the connection is broken and the radio operator will know that the information was not received.
While the information should be in NTS message format so as to not jam up the airways by transmitting extra, unnecessary data, if there is no one that can understand the NTS message format, it can be sent in plain text that anyone can read. An easily read list of needed supplies, request for medical support, for advice, or anything else can be sent.
Reliable error free information in text format when cell phones and land line phones are heavily loaded
It is often true that during an emergency that all cell phones and land line phones are overloaded. It is because the phone systems were never meant to handle that many phone calls simultaneously. In most cases all that happens when trying to call during emergency conditions (when you need the phone the most) is that you hear a busy signal. This condition may last for days. Emergency information MUST go out without delay. Lives may depend on it. Packet Radio helps fill in the gap, as explained in the previous section. It is independent of all normal services and, as such, can work when all else fails.
When long lists need to be sent, and FAX does not work, packet radio is an ideal method for getting this information out. Also, when names must be spelled right and detailed instructions must be understood it is less likely that it will be misunderstood when it is "written" rather than relayed over "voice" radio.
However, that being said, try using the cell phones and land line phones, as well as FAX as long as they are working. They are great communication tools when they are working and everyone knows how to use them. Do not assume that because the power is out and there are no lights that the phone system is down. It may not be down. Also, remember that it is more likely that you can call out-of-state rather than within it. The phone system was designed to work that way during emergency conditions. So, try the usual communications first before immediately setting up Packet Radio as a first response.
Emergency NTS (National Traffic System) message information both for outgoing and incoming transmissions
Of all modes of communicating information in an emergency, NTS messaging is one of the most important. This is because the format lends itself to sending the most information with the shortest transmission. Even amateur radio will start to "bog down" with all the information that needs to be passed. Information needs to be passed within the local community, but also within the county, and from state to state. A whole webpage is needed to adequately discuss the importance of NTS and how to use it.
But because NTS traffic is so important, the BEARS Packet Radio has forwarded to it all the NTS traffic for the entire San Fernando Valley (zip codes 91000 - 92000). As we are handling our own issues, we also need to think about helping our neighbors with theirs. There may be something with can help them with, and conversely, there may be something they can help us with. The NTS format dictates that the emergency level be part of the message so that everyone handles the most critical things first. When those are taken care of though, there can be health and welfare messages sent out-of-state to concerned family members to let them know that their loved ones in California are OK. Otherwise it may be weeks before they really know this in a really bad emergency.
A message board similar to e-mail is available when the internet is not available
When one is connecting to their Packet Radio system with a computer, whether at the EOC or remotely, typing kg6vgg-1 and ENTER, will connect to the BEARS PBBS (Personal Bulletin Board Service) or message board. It will say something similar to this:
cmd:*** CONNECTED to KG6VGG-1[KPC3P-8.3-HM$]
97321 BYTES AVAILABLE
THERE ARE 7 MESSAGES NUMBERED 3-10
ENTER COMMAND: B,J,K,L,R,S, or Help > Typing help and then pressing ENTER will explain in detail what each command does, but the essence is that L lists the messages, R followed by the message # allows one to read that message, and S followed by the callsign allows one to leave a message for that callsign. SB leaves a message (a bulletin) that is readable to anyone that connects. If a bulletin is left for all BEARS, type SB BEARS, so that is obvious that all of the members should read it. It is important to realize that a message left for a certain callsign is only visible if that callsign connects.
IMPORTANT: During non-emergencies any message can be left. During emergencies, only leave essential information.
There are two reasons for this:
- The memory in a TNC is only 100Kb. There needs to be space for essential messages
- When one is in emergency mode, it is helpful to not have to look through
pages and pages of "Hi, I just thought I would say hello".
DURING EMERGENCY SITUATIONS ALL NON ESSENTIAL MESSAGES WILL BE DELETED.
- One last WARNING! Remember, anyone with Packet Radio capability can look at the messages.
As CVD members and being FCC regulated, be sensitive to messages that someone might find
offensive
Packet Radio Operation
It is important to make the most effective use of any radio resources selected. The rules for effective radio communications are modified in the descriptive text to be specific to Packet Radio. The general rules for effective Packet Radio use are the same as for effective communication on any radio and are:
- Think about your message
- Establish communications
- Exchange your information succinctly
- Confirm receipt of your message
- Close the transaction.
Think about your message
The worst time to think about your message is after you have begun transmitting. Think about the information you need to transmit, who will receive it and what is the best way to organize it. The minute you take organizing your thoughts can save many minutes of clarifications. You might even want to write it down. This is even more important for Packet Radio. When a line of text is completed and the ENTER key is pushed, it can not be changed. Read what you have written and BACKSPACE to an error and corrected it. This is a DOS protocol, so everything has to be rewritten from the error to the end of the sentence. Check each line and correct (if necessary), before pushing ENTER.
Establish Communications
You can't presume that the person you need to communicate with is available and prepared to receive your message. You first transmission is to establish this connection. The way this should work is:
- Be certain you are on the correct frequency.
- Connect to the other station with a C callsign; ie C KG6VGG-1
- Wait to see the message that says connected
Exchange Your Information Succinctly
After the other party acknowledges your call transmit your information. This may involve a number of transmissions between you and the other party. It is most effective to transmit information in small increments. Transmit some information then allow the receiving station to acknowledge the receipt. This way if there is a problem with part of your transmission it won't be necessary to repeat your whole transmission.
- If you are communicating keyboard to keyboard type a short introduction and push ENTER. This is simplex communications, so you type a message and push ENTER and then they do the same. You see what they type and they see what you type. This is the equivalent of an internet chat room.
- Push CNTL C, then D, and then ENTER to disconnect from the other station
when you are finished communicating. THIS IS IMPORTANT. No one else can connect
while you are connected, and the connection will not "timeout" for 15 minutes to
allow others to connect.
or If connecting to a mailbox (the more usual situation), follow the instruction given below.
- Type SP (or SB) callsign to begin a message and push ENTER
- Put in a short descriptive title when asked and push ENTER
- Type in your message in lines of less than 50 characters, check the grammar and spelling (backspace, correct, and rewrite if necessary), and then push ENTER
- Continue writing lines of text and pushing ENTER until the message is complete
- Put your callsign on the last line and push ENTER
- Push CNTL Z on a line by itself and then push ENTER
- THE MESSAGE IS SENT!
- Push L and then ENTER to see if your message is listed
- Push R, a space, your message number, and then ENTER to read your message to make sure you were clear
- Push K, a space, your message number, and then ENTER to delete your message if you find the message is not clear, and start over again with SP and a callsign
- Push B and then ENTER to disconnect from the other station. THIS IS IMPORTANT. None else can connect while you are connected, and the connection will not "timeout" for 15 minutes to allow others to connect.
Confirm Receipt of Your Information
If operating keyboard to keyboard, after you have transmitted your whole message it's a good idea to have the receiving party feed back their understanding of your information.
Close the Transmission
If operating keyboard to keyboard, to indicate that you have completed this message, identify yourself and say "clear ".
Packet Radio Identification
How are you identified? The Packet Radio ID is sent as part of the transmission and needs to be in the TNC. When interfacing to the TNC with the computer, type mycall and hit ENTER. The radio ID will be shown. To change MYCALL, type mycall callsign. For example: mycall kg6squ ENTER will change mycall to kg6squ until someone changes it again.
-
The Station ID
- For the main Packet Radio station at the EOC, "mycall" should be the club callsign (kg6vgg) under normal conditions. This is to identify this Packet Station as being located at the EOC and being the main Packet Radio station. However under emergency conditions change "mycall" to PKC (for packet control)
- For an individual station "mycall" should be the callsign of whichever ham radio operator is at the control point for that Packet Radio station under non-emergency conditions, but under emergency conditions use the tactical callsign of PK1, PK2, etc. to make assignment of control operator and reassignment of control operator easier for the IC
Packet Radio Frequencies
Some CDV members belong to the Burbank Emergency Amateur Radio Service (BEARS). These are people who have been licensed by the FCC to operate amateur radios stations. The BEARS have designated 145.03 MHz for their use as the main frequency for packet radio (since NTS traffic is being forwarded here), though additional frequencies may be assigned under certain circumstances for keyboard to keyboard conversations. :
The frequencies that should be used for Packet Radio in southern California is decided by TASMA; Two-Meter Area Spectrum Management Association. While there is no legally binding requirement to follow these guidelines, it is a good idea to allow this group to coordinate with ham radio clubs to establish best practices.
Their guidelines say:
144.970 - 145.090 Digital (packet): 20 kHz spacing; 9600 baud FSK packet on 144.990
145.610 - 145.690 Digital (packet): 20 kHz spacing
| Tactical Callsign | Frequency (MHz) | Remarks | Local Packet Connections |
| none | 144.970 | none | ? |
| none | 144.990 | 9600 baud | ? |
| none | 145.010 | very quiet | K6VE-5,-10 |
| PKC PK1 PK2 ... (see Packet Radio Identification) |
145.030 | very active | K6VE-5, -10, KG6VGG-1, KG6SQU-1, WA6JFK-1,-4, KC6HBB-1, OJAI, SNOW |
| none | 145.050 | none | Have not seen anyone connected here |
| none | 145.070 | very quiet | W6JW-3 |
| none | 145.090 | none | K6VE-5,-10, K6CF-2 |
| Tactical Callsign | Frequency (MHz) | Remarks | Local Packet Connections |
| none | 145.610 | none | ? |
| none | 145.630 | none | ? |
| none | 145.650 | none | COAST |
| none | 145.670 | none | K6YRA, WB6UCD-9 |
| none | 145.690 | none | AB6QK, K6SY, KA6ZYF, W6RCL-2 |
We do not have exclusive use of any of these frequencies. We have to be flexible enough under emergency conditions to switch to other frequencies if it is found that a frequency is overloaded. Each person needs to have another 2-M, or 440 MHz radio so that they may be contacted and told to change to another operating frequency if the need arises. As in any aspect of HAM radio, flexibility is the key to success.
If we discover that one frequency is being heavily used, the district supervisor may order everyone to switch to another frequency.
David Fleming is the BEARS' packet radio sysop and the contact for issues relating to packet radio!
For more Packet Radio information and/or help contact David Fleming at the following e-mail: BEARS-Packet@BurbankCDV.org