Part 1: How to get started and what you need....................1

Part 2: How to get on the air..................................................2

Part 3: Common Commands...................................................4

Part 4: Using Digipeaters and Nodes...................................6

Part 5: Using a Packet Bulletin System................................8

Part 6: BBS Commands..........................................................10

Part 7: Hierarchical Addressing...........................................13

Part 8: Understanding packet messages............................15

Part 9: White pages...............................................................17

Part 10: Packet NODE Network...........................................19

Part 11: NODE Network - continued..................................20

Part 12: The National Traffic System.................................23

Part 13: TNC Commands......................................................25

Part 14: TNC Commands - continued.................................27

Part 15: Tips for easier Operating.......................................28

Part 16: Reviewing and Quiz................................................29

Part 17: Answers To Quiz....................................................30

Part 18: Conclusion...............................................................32

Packet Radio is the latest major development to hit the world of Amateur Radio. If you haven't already been caught by the "packet bug", you're probably wondering what it's all about and why so many people are so excited about it. Well, continue reading, because you're about to find out.

Packet seems to offer something different from other facets of Amateur Radio, yet it can be used for everything from a local QSO to a DX contact 2500 miles away (on 2 meters!), for electronic mail, message transmission, emergency communications, or just plain tinkering in the world of digital communications. It presents a new challenge for those tired of the QRM on the low bands, a new mode for those already on FM, and a better, faster means of message handling for those on RTTY. Packet is for the Rag chewer, the traffic handler, the experimenter, and the casual operator.

A ham can get involved very easily with relatively small out-of- pocket expenses.All you need is a 2 meter transceiver, a computer or a terminal, and a TNC. You probably already have the two meter rig and a computer of some kind, so all you need to buy is the TNC, which costs just over $300.

The TNC is the Terminal Node Controller, the little black box that's wired between the computer and the radio. It acts very much like a modem when connecting a computer to the phone lines. It converts the data from the computer into AFSK tones for the transmission and changes the tones received by the radio into data for the computer. It's a simple matter of wiring up a plug and a couple of jacks to become fully operational.

Packet is communications between people either direct or indirect. You can work keyboard to keyboard or use electronic mailboxes or bulletin board systems to leave messages. Due to the error checking by the TNC, all of it is error free, too. (That is, as error free as the person at the keyboard types it.) As the data is received it's continuously checked for errors, and it isn't accepted unless it's correct. you don't miss the information if it has errors, however, because the information is re-sent again. I'll go into how this is accomplished in a later part of this series.

The data that is transmitted is collected in the TNC and sent as bursts, or packets, of information; hence the name. Each packet has the callsign or address of who it's going to, who it's coming from and the route between the two stations included, along with the data and error checking. Since up to 256 characters can be included in each packet, more than three lines of text can be sent in a matter of a couple seconds. There is plenty of time between packets for several stations to be using the same frequency at the same time.

If all of this sounds confusing, don't let it bother you, because that little black box, the TNC, does everything for you automatically. Packet might seem very confusing at first, but in a day or two you're in there with the best of them. In this series I'll be telling you more about packet -- how you get on the air, how to use it to your best advantage, and ways to improve your operation. We'll talk about that little black box, the TNC, and tell you about all it's inner most secrets. We'll discuss mailboxes, bulletins board systems, and the packet networks that allow you to work stations hundreds of miles away using just a low powered rig on 2 meters, 220 or 450.

The World of Packet Radio Awaits You!

TOP

In the first part of this series we told you, in general terms, what packet radio was all about...what it is, its uses, the equipment used and, generally, how it's transmitted. Now we're going to tell you how to get on the air, make a QSO, and become familiar with your packet station. Whether you're new to packet, having just received a new TNC, have been involved for just a short time, or are one of the "old timers" with four or five years of experience, this should help all of you. Even if you don't yet own a TNC, you should keep this article handy for future use. I'll bet you'll be joining us soon.

The equipment needed to get on the air is a VHF transceiver, a computer or terminal, and a TNC - the little black box we talked about in part 1. (There is packet activity on hf, but VHF is where all the action is. It's the best place to start out in packet.) The TNC contains a modem amd is equivalent to the modem used to connect your computer to the phone lines, except that it also contains special software thats specially designed for ham radio packet use.

When you buy a TNC and take it out of the box, you'll find cables supplied for connecting it to the radio, but you'll have to attach the appropriate mic and speaker jack connectors for the radio you're going to use. You also have to furnish the cable that connects the TNC to your computer or terminal. In most cases, the standard RS-232 port is used between the TNC and computer, however this varies with the type of computer and TNC used. The operating manuals supplied with the TNC's have a good write up on the various computers and cabling needed. I would advise that you read the introduction and setup procedures for your particular TNC very carefully. Most companies have supplied excellent manuals, and you usually can figure out all of your set up problems from the information supplied in the manual.

Once you have everything wired and connected together, turn on the computer, load a terminal program (anything used for a phone modem will work well for packet) and get into receive mode. Now turn on the radio and make sure the volume is turned up a quarter turn (about "10 or 11 o'clock" position) and make sure the squelch is set.

It should be at the point where the background noise disappears, just as it would be for a voice QSO. Next, turn on the TNC. You should get a "greeting" or a sign on message showing the manufacturer's name, software version, ect. If you see a bunch of gibberish, such as &tf$d.#ssan>m, it means that the data rate of the TNC and computer are not the same. This data rate is better known as the baud rate. The Baud rate of the TNC has to match the baud rate used by your computer terminal program and is easily adjusted. Check your TNC manual for this procedure, as it varies from TNC to TNC. If you don't see a "greeting" or the gibberish, check your cables and connections. Make sure that you have everything connected properly, that the right wires are on the right pins, ect.

Now we need to explain the three levels of communicating you can do from the keyboard.

First, you can communicate with your computer for setting up the terminal program;

Second, you can communicate with the TNC;

Third, you can communicate with the radio;

It's very important that you know which level you're in when working packet. I can't help you much with the computer level, since that varies with manufacturers, model and the terminal program you're using, but once you get the terminal program ready to receive data, you're ready to talk to the TNC. First, do a CNTL C , this puts the TNC in COMMAND Mode, the level where you communicate directly with the TNC from the keyboard. You should see "cmd:" on your screen. ENTER: MYCALL ------

INTRODUCTION TO PACKET RADIO - PART 2 PAGE 3

In part 2 I talked about how to get on the air and make your first QSO. Now lets take a look at some of the commands that are available in your TNC to help improve your station operation.

TNC COMMANDS: The TNC, or Terminal Node Controller, that "little black box of tricks" we've talked about in the past, has more than 100 different commands for you to use. You're able to to customize your packet operating with these commands and turn on and off various features as you wish. Not all TNC's are exactly alike, but all have pretty much the same functions. I'll be using the commands used by the TNC2 and clones in my examples.

We covered a few of the commands previously: CONTROL C for entering command mode,

Mycall, Monitor, Connect, and Disconnect. Now lets discuss a few that can change the way your station functions.

ECHO: This command tells the TNC whether or not it should send what you type back to the monitor screen. If you don't see anything when you type, set ECHO to ON. If yyoouu ssee ddoouubbllee, like that, set ECHO OFF. This setting will depend on how your particular computer system functions.

CONV: (converse mode) Your TNC will automatically switch to this mode when you connect with someone, but you can also do it by entering CONV (CR) at the Cmd: prompt. When in converse mode, anything you type will be transmitted via the path you set with UNPROTO. (See Next Paragragh.) Anyone in monitor mode will be able to read what you transmit. Packets in converse mode are sent only once and are not acknowledged, so there is no guarenteer that they'll get through. This mode is used frequently for sending CQ's.

UNPROTO: This command designates the path used when in converse mode. The default is CQ, but you can enter a series of digipeaters if you wish, or a specific group or club name. Some examples: CQ v ZL0STB,ZL1IT PBBS v ZL1BW,ZL1IT

Remember, you have to change UNPROTO for use on different frequencies, unless you leave it set simply to "CQ".

FRACK: This determines how long your TNC will wait for an acknowledgement before resending a packet. It shouldn't be set too short, or you simly clutter up the frequency, yet it shouldn't be too long, or you'll spend too much time waiting. I use FRACK set to 7, and have found that to be an overall good value.

DWAIT: Used to avoid collisions, DWAIT is the number of time units the TNC will wait after hearing data on the channel before it transmits. I have DWAIT set to 16, and have found that to work well.

PACLEN: Determines the number of characters in your packets, ranging from 1 to 256. The more characters you send per packet, the longer it takes to transmit the information and your chances are of noise, interference or another station wiping it out. I've found a PACLEN of 80, which is the length of one line, to be a good value. When working a station nearby, PACLEN can be increased. When working a distant station, it should be decrease.

RETRY: Your TNC will retransmit a packet if it doesn't receive an acknowledgement from the station you're working. RETRY indicates the number of times the TNC will try to get the packet through before giving up and disconnecting. This can be set from 1 to 15, but I've found 8 to 10 to work well. Less than that causes an unnecessary disconnect if the channel happens to be busy, but more than that clutters up the channel.

INTRODUCTION TO PACKET RADIO - PART 3 PAGE 5

The following TNC commands affect the monitoring mode and what you see on the screen.

MONITOR: This must be ON for you to monitor anything. When ON, you see packets

from other stations on the frequency you're tuned to. What packets you see is

determined by other commands from the list below. if MONITOR is OFF, you

only see packets sent to you while you're connected to another station.

MALL: If MALL is ON, you receive packets from other stations that are connected to other

stations, as well as packets sent to unproto (unconnected) mode. This should be ON for "reading the mail". If MALL is OFF, you receive only packet sent in unproto mode by

other stations.

MCOM: If on, you see connect <C>, disconnect <D>, acknowledge <UA> and

busy <DM> frames in addition to information packets <I1>. If OFF, only information

packets are seen.

MCON: If ON, you see packets from other stations while you're connected to

someone else. This can get very confusing, but is useful when your path is bad

and you want to see if your packets are being digipeated okay. If OFF, the monitoring of other stations is stopped when you're connected to another station.

MRPT: If ON, you see a display of all the stations used as digipeaters along with his station originating the packet and the destination station. If OFF, you see only the originating

and destination stations. For example, if you have MRPT ON, you might see a transmission

such as this:

ZL1BW>ZL1NG,ZL1IT-1*:I'LL BE LEAVING NOW!

If MRPT OFF, the same transmission would look like this:

ZL1BW>ZL1NG:I'LL BE LEAVING NOW!

In the first case, you can see that the ZL1IT-1 digipeater was being used. The asterick indicates which station you were hearing the packet from. In the second case you have no idea if digipeaters are being used or what station you were receiving.

HEADERLN: If you have this turned ON, the header of each packet is printed on a separate

line from the text. If OFF, both the header and packet text are printed on the same line.

MSTAMP: Monitored packets show the date and the time the packet was received if MSTAMP is ON. If it's OFF, date/time stamp is not shown.

NOTE: The date and time must be entered using the daytime command before the MSTAMP command will function.

I run my station with all of these commands, except MCON, turned ON so that I can really see what's happening on the frequency I'm monitoring. Try various combinations of these commands and then decide on the combination you like best for your station.

Digipeater is the term we use to describe a packet radio digital repeater. Unlike the FM voice repeaters, most digipeaters operate on simplex and do not receive and transmit similaneously. They receive the digital information, temporarily store it and them turn around and retransmit it.

Your TNC will allow you to enter up to eight digipeaters in your connect sequence, but using more than 3 usually means long waits, lots of repeated packets, and frequent disconnects, due to noise and other signals encountered on the frequency. When entering the list of digipeaters in your connect sequence, you must make sure that you enter them in the exact order that your signal will use them. You must separate the calls by commas, without any spaces, and the EXACT callsigns must be used, including the SSID, if any. That means you need to know what digipeaters are out there before you begin randomly trying to connect to someone. Turn MONITOR ON and watch for the paths that other stations are using.

Here are some examples of proper connect sequences:

C ZL1RAH-1 V ZL1BW-1

C ZR1CE V ZL1IT-1,ZL1ADC

C ZL1NG V ZL1IT-1,ZL0STB,ZR1AFC-1

The "v" means via. In the first example the sequence shown means:

Connect to ZL1RAH-1 via ZL1BW-1

Something to remember when using digipeaters is the difference between making a connection

and sending information packets. If the path isn't all that good, you might be able to get a connect request through, but will have a difficult time with packets after that. The connect request is short so it has much less of a chance of being destroyed by noise or collisions than a packet containing information. Keeping information packets short can help keep retries down when the path is less than ideal.

Net/Rom, TheNet, G8BPQ packet switch and the KA-Node are names that refer to a device called a packet node, another means of connecting to other packet stations. Later on in this series you'll find a complete review of node operation, but for now we'll cover the basics so that you can begin using the node network. The difference you should note here is that you connect to a node rather than using it in a connect path as you do with a digipeater.

First, you need to determine what nodes are located close to you. You can do this by monitoring and watching for an ID or by watching to see what other stations in your area are using. You'll note that most nodes have an alias ID in addition to it's callsign. Once you determine the callsign or alias of a local node, you connect to it the same way as you connect to any other packet station. You may use either the callsign or the alias to make the connection. For example, the node I operate has the alias ID of SF and the callsign of WB9LOZ-2, so you could connect to it using "C SF" or "C WB9LOZ-2". Either one will work.

When you connect to a node, your TNC automatically switches to converse mode, just like when you connect to any packet station. Anything you now type is sent to the node as a packet, and the node acknowledges each packet back to your TNC. For the remainder of your connection your TNC works only with this one node.

INTRODUCTION TO PACKET RADIO - PART 4 PAGE 7

To use the node network to connect to another local station, you simply enter a connect sequence request as though you were connecting direct from your TNC, such as "C ZL1BW".

You do this, however, while you ARE STILL CONNECTED TO THE NODE. The node will then retransmit your connect request and you'll receive one of two responses: "Connected to (callsign)" or "Failure with (callsign)". Once you're connected you hold your QSO just as if you had connected direct or via a digipeater. When you're finished, go to command mode on your TNC (Ctrl C) and enter "D" (CR) and you will be disconnected from the node and the station you were working.

(Note: If the node you're using is a G8BPQ packet switch, it might have several frequency ports. You'll have to enter a port number between the C and the callsign in your request to indicate the frequency you want to use, such as "C 2 ZL0STB". Enter "PORTS" for a port list.)

When you're connected to a node enter "NODES" <CR> and you'll receive a list of other nodes that you can reach on the network from the node you're using. You'll note that the node list will vary in length and in the calls listed as you move from frequency, since all frequencies are not linked together. The list gives both an alias ID and a callsign for each node. The alias ID often gives you a hint as to where the node is located, but not always. To find out for sure where a node is located you'll need to get a copy of the descriptive node listings that are available on most packet bulletin board systems. These complete lists give the alias, callsign, location, frequency and other information on each node in the network.

To connect to a station in another area using the node network you first must determine which node is closest to the station you want to work. For demonstration purposes, let's say we want to connect to N6ZYX. He's told you he uses the W6AMT-3 node, so you check the node list and see that SFO3:W6AMT-3 is listed. WHILE STILL CONNECTED TO YOUR LOCAL NODE you first connect to the distant node by sending a normal connect request, in this case "C W6AMT-3". Your TNC will send this as a packet to your local node and your local node will acknowledge it. The network will then go to work for you and find the best path between your local node and the one you're trying to reach. You might have to be a little patient here, as it sometimes takes a few minutes for the connection to be completed. You'll then see one of two responses: "Connected to W6AMT-3" or "Failure with W6AMT-3". If it can't connect for some reason, try again later. It could be that W6AMT-3 is temporarily off the air or the path has decayed and is no longer available. We're going to be positive here and say we received the first option.

Once you're connected to W6AMT-3, enter "c N6XYZ". Again, your TNC will send this as a packet to your local node and the local node will acknowledge it and send it down the path to W6AMT-3. W6AMT-3 will attempt to connect to N6XYZ. Here again you'll get one of two responses: "Connected to N6XYZ" or Failure with N6XYZ". If you get connected, you hold your QSO just as you normally would, but there's one BIG difference --- your TNC is receiving acknowledgements from your local node, and N6XYZ is receiving acknowledgements from W6AMT-3. The acknowledgements do not have to travel the entire distance between the two end stations. Each node in the path handles the acknowledgements with the next node in line. Because of this, retries are greatly reduced, and your packets get through much faster.

When you're finished with the QSO, you disconnect in the normal manner --go to command mode on your TNC and enter "D" <CR>. The entire path will then disconnect automatically for you.

Nodes offer a variety of other features besides allowing you to connect to other stations, and we'll look at those in parts 10 and 11 of this series.

This information is based on WORLI software, so the instructions might vary slightly for users of AA4RE, WA7MBL, MSYS or other typ systems. Use the H - Help command on your BBS if some of these commands do not work as described here.

You connect to a bulletin board system (BBS) exactly the same way as you connect any other station. Once connected, you'll receive a welcoming message, some information on the BBS and instructions. This information will vary from system to system. Read the information and instructions carefully. The first time you connect you'll receive a request to enter your name, QTH, zip code and home BBS for the system user file. On some systems, the software will not let you do anything else until you have entered this information. When you receive the welcoming message, you'll note that the last line ends with a >. This is known as the prompt, and is where you enter the command you want performed next.

You enter your name using the letter N followed by a space and then your first name, such as: N LARRY.  Your QTH is entered using NQ followed by a space then your full city name and two letter state abbreviation, such as: NQ OTTERY, SA. You enter your zip code with NZ followed by a space and your digit zip. Your "home BBS" is the system that you plan to use regularly and want all of your personal messages delivered to. Make sure that it's a full service BBS, not a personal mailbox, since only fullservice systems are included in the message forwarding network. You enter your home BBS by typing NH followed by a space and then the call of the BBS, such as NH ZL0STB. (Note: SSID's are not used with BBS operaton exept for when making the connection. The BBS software ignores all SSIDs.) This user information is stored at the local BBS and is also sent to a central data bank known as the "White Pages Directory". The information can be accessed by anyone. System Operators (sysops) use it for determining your home BBS when forwarding messages, and you can use it to find the name, QTH and home BBS of our friends. How to use "White Pages" will be discussed in part 9 of this series.

When checking into a BBS for the first time, you should become familiar with the commands available to you. Each BBS or mailbox is a little different from the next, so read the introduction carefully and follow the directions. If you don't know what to do next, enter H for help instructions. Make note of the command letters, enter only the one command at a time, and make sure you enter them correctly. Computers are not very forgiving and expect things to be entered in proper form. Take your time, check out the features that the BBS offers and enjoy yourself. There's no need to feel rushed or intimidated. If you get to a point where you don't know what to do next, don't give up and disconnect, enter H again for further HELP. That's what it's there for! I suggest that you make a printer copy of the complete help file so that you have it available as a reference when using the BBS.

Now lets go through the basic procedures you should follow when checking into a BBS. If there are personal messages addressed to your call, the BBS will list them for you following a welcome message. Note the message number(s). At the > prompt, the first thing you should always do is list the new messages, by entering L. The BBS program updates the user file each time you check in, only new messages that have been received by the system will be included in your list. The first time you'll receive all of them, since they're all new to you. This list can be very long, as many systems have more than 200 active messages on line. When you receive the list, note the numbers of the messages you're interested in reading.

INTRODUCTION TO PACKET RADIO - PART 5 PAGE 9

Next, read the messages you're interested in. You do this by entering R xxxxx, where the x's represent the message number, such as R 45312. Note that there is a space between the command and the number. It's best to have the buffer or printer turned on when reading messages, because they're apt to come faster than you're able to read them. You should have a means of saving them for reading later after you have disconnected. If there were messages addressed to you, you should erase or "kill" them once you have read them. You can do this with the "KM" command, which means "KILL MINE". This command will erase all messages that are addressed to you that have been read. You can also kill each messgae individually by entering K xxxxx, where the x's are the message number.

Once you've read all the messages you're interested in, you have several options. You can look at back at old messages, send messages to other stations, see what's available in the files section, download a file, upload a file, check the list of stations that have recently checked in to the BBS or stations that have been heard on frequency, monitor other frequencies used by the BBS, use the gateway feature (if available), check the status of the BBS tasks, or a variety of other things.

We look at the BBS commands in detail next.

In the previous section we discussed the basics of using a packet bulletin board system. Now lets look at the BBS commands in more detail. This information is based on the WORLI software so some of the commands might vary slightly on systems using different software, such as REBBS, MSYS, WA7MBL, ect. Use h (help) on your BBS if you find that a command doesn't work as described here.

LIST COMMAND: The first thing you should do when logging on to the BBS is to use the LIST command. There are many variations available, but L, by itself, is the one used most often.

L (list) - lists all new messages, except other user's personal messages, that have been entered since you last lgged in.

If you want to list specific messages, you may use one of the following variations of the L cmd.

LM - (LIST MINE) - Lists all messages addressed to you.

Lx - Lists all messages of the type designated by "x". Example: LB will list all Bulletins

L # - Lists messages back to and including number #. Example: L 4050 will list all messages, except personal messages to others, from the latest one back to #4050.

LL #- Lists the last # messages. Example: LL 20 lists the last 20 messages received at the BBS, excluding other's personal messages.

L 1 - Lists ALL non-personal messages.

L> callsign - Lists all messages TO callsign indicated. Example: L> ZL1RAH

L< callsign - Lists all messages FROM callsign indicated. Example: L< ZL1RAH

L@ designator - Lists all messages that have that "designator" in the @BBS column of the message header. Example: L@ALLCAN will list all messages with ALLCAN in the @BBS column.

READ COMMAND: To read a message, you enter R followed by a space then the message number. Example: To read message 5732, you'd enter: R 5732. You also have the option of using the RH command, which will give you all of the forwarding headers in detail, rather than just giving you the path. Example: To read message 5732 with full headers, you'd enter: RH 5732. There is one other version of READ command, and that's RM. Entering RM by itself will give you all of the messages addressed to you that have not yet been read.

ERASING MESSAGES: Once you have read a personal message, please erase it. The sysop will appreciate your help in clearing up "dead" messages. You use the K - KILL command to do this. you can enter K #, such as K 5732, which will erase that particular message, or you can type KM, which will erase all of the personal messages you have read. If you use KM command, the BBS will list the message numbers for you as they're killed.

THE "S" COMMAND: S (send) and (status): The letter by itself will give you a reading of the BBS status on WORLI systems, showing the callsigns of stations using the system, the time they connected, the ports and tasks they're using, etc. It also shows information on the messages waiting for users and those waiting to be forwarded to other bulletin board systems.S, by itself, on other systems will either prompt you for further information on sending a message, or it will give you an "illegal command" error prompt.

To use the "S" command for sending a message it must be further defined. There are three types of messages found on a packet bulletin board system: Personal, Bulletin, and Traffic.

SP callsign - used for sending personal messages to other stations

SB x - used for sending a bulletin

ST - used for sending a message that's going to be handled by the National Traffic System.

You're able to send a message to one particular person, to everyone on the local BBS, to everyone at every BBS in Northen California, in Southern California, in the entire State, or all across the entire country. It all depends on your addressing.

INTRODUCTION TO PACKET RADIO - PART 6 PAGE 11

At the BBS prompt you enter the appropriate command (SP, SB, or ST) followed by a space and then the addressee. The addressee can be a callsign or it can be something of a general nature, such as ALL, QST, ARES, etc. Examples: SP WB9LOZ SB ALL SB SWOP . All commands, of course, must be followed by a <CR>.

If you wish to send the message to someone at another BBS, you have to indicate the call of the other BBS and the two letter abbreviation of the state it's located in following the call of the addressee. For example, to send a message to N5PQ, who uses the W5XYZ BBS in Texas, you would enter: SP N5PQ @ W5XYZ.TX

The BBS call and the state abbreviation are separated by a period. This is the bare minimum required for delivery of messages going out of state. A more complete system of addressing is available. It's helpful in directing your messages to stations in the U.S more quickly and is required formessages going to stations outside the U.S. It's called hierarchical addressing, and its covered in detail in the next part of this series.

To send a general message or bulletin to more than just the local BBS, you need to use a designator in place of the BBS call. The designator indicates the area where you want the message distributed. In Northern California,

ALLCAN - indicates that you want the message sent to all Northern California BBS's, which includes all of them from Santa Cruz, Gilroy, and Fresno northward.

ALLCAS - is used to send a message to all BBS's in the southern part of the state.

ALLCA - is used for sending a message to EVERY BBS in the state.

ALLUSW - is used for distribution to CA, AZ, NV, OR, WA and ID

USA - is the desigator to use for sending a message to EVERY BBS IN THE USA.Extreme care should be used when using the USA designator. Please make sure that the subject matter is of interest to packet users everywhere and please keep the message as short as possible. "FOR SWOP" messages should NOT be sent with the USA designator. The National HF Packet Network is somewhat fragile, due to varying band conditions, so unnecessary traffic can keep more important traffic from getting through.

Here are a few examples of how you would correctly address a bulletin-type message for general distribution: SB ALL @ALLACAN SB SWOP @ALLCA SB AMSAT @USA

If you have traffic for the National Traffic System, you must use a special format. NTS messages are entered as ST ZIPCODE @ NTSXX, where the XX is the two letter state abbreviation. Examples: ST 03452 @ NTSNH ST 60626 @ NTSIL

When you have the address line of your message complete, you enter a carriage return (<CR>). You'll then receive a prompt asking for the SUBJECT or TITLE of the message. Enter a brief description of what the message will be about, followed by a <CR> . Next, you'll be asked to enter the TEXT of the message. When entering the text, you should insert carriage returns at the end of each line, as if you were typing a letter. A normal line has a maximum of 80 characters, so when you have 70 to 75 characters typed, enter a carriage return and continue on the next line. this will prevent words from wrapping around to the next line and the program inserting an unnecessary blank line in the text. After you have completed the text, you end off the message with a Ctrl Z. (You send a CONTROL Z by holding down both the CONTROL key and the Z key simultaneously.) You must follow the CONTROL Z with a carriage return. (Some systems will also allow you to use /ex to end a message.) When you receive the BBS prompt, you'll know that the message has ben accepted by the system.

W (WHAT) - Entering W, by itself, gives you a list of directories available on the BBS along with an associated letter for each directory, called the directory ID.

Wd - Gives a list of the files in the directory indicated by d. The "d" is the directory ID you obtain with the W command.

D (DOWNLOAD) - Used for reading filesfrom a directory. Must be used with a directory ID and filename using the following form: Dd filename

The "d", again, is the directory ID and the filename must be entered exactly as listed in the directory. Example: DG FCCEXAM>INF

U (UPLOAD) - Used for uploading (sending) a file to the BBS. The command must be used with a directory ID, followed by the filename you're assigning to the file, using the form: Ud filename.

The "d" indicates the ID of the directory where you want to enter the file. Filenames can have up to 8 characters preceding the dot and 3 characters following the dot.

Example: Um FLEAMKT.INF would upload a file named FLEAMKT.INF into the directory with the M ID. The BBS program will not allow you to upload a file with a filename that already exists, and some directories are set by your local sysop for downloading only.

GENERAL MISCELLANEOUS COMMANDS:

I (INFO) - Gives you details on the hardware, software, and RF facilities of the BBS you're using, or on some other systems, a page of upcoming events, helpful hints, or other useful information.

J - Displays a listing of stations that were heard by the BBS or that connected to the BBS. Must be used with a port identifier, such as JA, JB, ect. J by itself will list the port ID's fo you.

M (MONITOR) - Used for monitoring the activity on another port of the BBS. Must be used with a port identifier, such as MA, MB, ect. M by itself will list the port ID's. (Not available on all systems)

B (BYE) - When you're finished using the BBS, you enter a B to disconnect.

HELP DOCUMENT: Every BBS has help available for the user. Simply enter an H and follow the directories given. In most cases, an H followed by a space and a letter of the command you want help on will give you the specific information you need. For example, if you want to know more about the download command, you would enter H D at the prompt.

There are other commands available that are specific to the particular software being used. Check your local BBS for a complete list of commands available to you.

WORLI, N6VV, and VE3GYQ have devised a scheme called HIERARCHICAL ADDRESSING. With hierarchical routing designators we have as oppertunity to improve traffic routing. no longer will a missing call in a BBS forwarding file cause a message to remain unforwarded, sysops will no longer have to burn the midnight oil trying to keep their forwarding files up to date, and messages will move much more directly toward their destination.

The format of hierarchical routing is:

addressee @ BBScall.#local area.state-province.country.continent.

It might look complicated, but it's not. First, note that each section of the format is separated by a period. Codes used for the continents and countries are standard, now accepted throughout the world. You should be able to find a list of them in the file section of your BBS. State and province codes are the recognised two-character codes established by the American and Canadian Offices. These may be found in the Callbook, your phone directory, or any zip code listing. don't guess on the state and province code if you aren't sure what it is, and make sure you use only the two letter abbreviation. You could send the message to the wrong state or province or keep it from being forwarded altogether. The code for the local area is optional, since most of you have no idea what code is being used in upper New York or in Iowa City, IA. If you do know it, please use it, since it will help get the message closer to where it's going.The code for Northern California is #NOCAL, and the code for Southern California is #SOCAL. You should use the appropriate one in the signature line at the end of each message you send. For messages going to outside the US or Canada, the local area is again optional and the state-province is not used.

Using the hierarchical format, here are some routing examples:

WB9LOZ @ W6PW.#NOCAL.CA.USA.NA

WB6LYI @ K6VE.#SOCAL.CA.USA.NA

KC6XC @ N4QQ.MD.USA.NA

VE3XYZ @ VE3RPT.ON.CAN.NA

JA1ABC @ JA1KSO.#42.JPN.AS

VK4AHD @ AX4BBS.AUS.OC

You'll note that the local area code is preceded by the octothorpe (now hows that for a $5 word?), better known as the number or pound sign. The reason is that the Japanese network, and possibly other areas , use routing numbers for the local area, which could get confused with zip and postal codes. Using the # on all local area codes will eliminate forwarding problems.

We need to emphasize two very important points: Hierarchical addressing DOES NOT indicate a forwarding PATH, and ONLY ONE BBS call should be included in the address. A list of BBS calls separated by periods will not get your message to its destination. In fact, it can cause your message to loop between BBS's and your message probably won't be delivered. The addressing scheme is said to be one area inside another area. Using my hierarchical address as an example, WB9LOZ @ W6PW.#NOCAL.CA.USA.NA , here's how you would describe the address: "WB9LOZ at W6PW which is in the Northern California which is in California which is in the USA which is in North America".

There are several BBS programs that implement hierarchical addressing now, including the WORLI, WA7MBL, AA4RE, MSYS and WD6CMU software. Check the ID block you receive when you log into the BBS. If it has an H in it, such as [RLI-11.11-CH$] or [4RE-02.10-HM$], your system supports it.

INTRODUCTION TO PACKET RADIO - PART 7 PAGE 14

This next section explains how the BBS software uses the hierarchical addressing scheme. We first have to understand how the software goes about matching items in the "@BBS" address with items in the forward file. For an example, let's say that we sent a message to TOM, W3IWI, who operates his own BBS and is located near Baltimore, Maryland. We would enter:

SP W3IWI @ W3IWI.MD.USA.NA

If the only entries in the forward file are California BBS's plus a list of state abbreviations, let's see how the message would be forwarded. The first thing the software does is attempt to find a match between the items in the forward file and the left-most item in the address field. In our case, it would not find W3IWI. If there isn't a match, it then moves to the next section to the right. It would find MD and that match would allow the next message to be forwarded. If it had found the call W3IWI, that entry would take precedence (because it is more left in the field than MD) and would of course also ensure delivery.

Here are some comments from the ones who devised the hierarchical addressing:

" There is another added benifit to this scheme. It involves Gatewaying between the BBS world and other networks, such as TCP/IP via SMTP. Much of the pioneer work in setting up the gatewaying protocols has been done by NN2Z, N3EUA, and PAOGRI, amongst others. The WORLI BBS package allows for the forwarding of mail between the BBS world and the SMTP world. Of note is in fact that the WA7MBL package has allowed exporting and importing for some time now. This means that we can take advantage of the TCP/IP host-names and their domain or hierarchical format for forwarding. Thus it is possible to send mail from the BBS to VE3BTZ as [email protected] or from SMTP to [email protected] and not have any ambiguity."

" The authors hope that this paper will serve as a starting place for improved message routing by means of implicit routing. Low-level (VHF) BBSs need only maintain state or province or country codes for distant BBSs, and route such traffic to their nearest HF Gateway. In turn, the HF station routes it to the desired state, where the receiving Gateway station would have a detailed list of the BBSs it serves."

This part of the series discusses, in detail, the various parts of the packet message. The following is an example of what you see when listing messages on a BBS. On some systems the information is displayed in a different order, but the same information is given.

4732 P 1084 WD5TLQ WA6XYZ N5SLE 0604/1240 Software working great!

4731 BI 771 PACKET WB9LOZ ALLUSW 0604/1154 Introduction to packet

4730 BF 2387 EXAMS W6NLG ALLCAN 0604/1020 Fcc Rules

The MESSAGE NUMBER is assigned by the BBS program when the message is received and it cannot be changed. The numbers are assigned sequentially.

The STATUS of the message includes several different bits of information. The first letter of the STATUS indicates the TYPE of message: B for Bulletin, P for Personal, or T for Traffic for the National Traffic System. Bulletins are messages of general interest to all users, and are available to be read by everyone using the system. Personal messages are listed only for the sender and the addressee, and they're the only ones that can read them. (Anyone in monitor mode could see a personal message as it's being sent over the air, of coarse.) The list above would have to have been requested by WA6XYZ since it lists an outgoing personal message. Traffic messages, type T, are messages used for handling traffic on the NTS. (Refere to part 12 of this series for information on NTS.)

STATUS also shows if the message has been read, has already been forwarded to all designated stations, is in the process of being forwarded, or is an "old" message. You might see one of these letters: Y - yes, it has been read, F - it has been forwarded, I - it's in the process of bein forwarded right now on another port, or O - the message has been on the BBS long enough to become an "old" message. "Old" can be anywhere from 2 days for an NTS message to 3 weeks for bulletins. The time frame for each message is specified by the local sysop. The "o" is mainly used to catch the attention of the sysop.

The SIZE indicates the combined total of characters, including punctuation in the message

TO is who the message is addressed to or it can be a message category. The call of the addressee is entered for a personal message, and for bulletins it could be ALL, EBARC, USERS,ect. TO is also used to categorized bulletins by particular topics. You might find a message addressed TO AMSAT, TO PACKET or TO SWOP, when it is actually a message about AMSAT, about PACKET or about equipment for SWOP. For NTS messages TO is the zip code of the addressee.

FROM shows the callsign of the station originating the message.

@BBS is used if you want a message to be forwarded to someone at another BBS or for general distribution using a forwarding designator. In the list shown above, the personal message would automatically be forwarded to WD5TLQ at the N5SLE BBS. By entering a special designator, such as ALLCAN, in the " @ BBS" column a message can be forwarded to a specific area. ( See Part 6 and 7 of this series for details on addressing messages and using forwarding designators.)

INTRODUCTION TO PACKET RADIO - PART 8 PAGE 16

Next is the DATE and TIME when the message was received at the BBS you're using. (If the message was originating at another BBS, the date and time when the message was originating entered will be shown in the forwarding headers, as explained below, and at the top of the message when you read it.) Keep in mind that the date and time indicated can be iether local time or GMT (Zulu Time) depending on the time used by the BBS.

The SUBJECT (or TITLE) is a short linetelling what the message is all about. It should be brief, but informative. For bulletin type messages, this is the information that determines whether or not a person is going to read your message when he sees it in the message list.

The parts of the message mentioned so far are all included in the header of the message, and are seen when listing messages. The hierarchical address and the message ID are not shown in the normal listing. On some systems, such as those using WORLI software, entering a semicolon after the list command give you this information. ( Example: LL 15 ;)

If the message has been forwarded from another BBS, forwarding headers are added at the top of the actual message text. This is information added by each BBS that was used to get the message from it's origination point to the destination. Each BBS adds one line showing the time the message was received by that particular BBS, its call sign, and usually the QTH, zip code, and message number. Other information is often added, at the discretion of the sysop there. If you use the RH command, rather than just R, when reading a message, such as RH 7823, you'll receive complete headers. With just the R, headers are reduced to a list of the BBS callsigns. Complete headers are useful if you want details on the path the message took to reach you or how long it took to be forwarded from system to system from the source to destination.

The TEXT of the message contains the information you want to convey to the reader. It can be of any length. When entering a message into a BBS, use carriage returns at the ends of your lines, as if you were using a typewriter. The normal screen width is 80 characters, so you should enter a carriage return prior to the 80th character on each line. Don't allow the automatic wrapping of lines to occur. A message entered without carriage returns is very difficult to read, as words are cut at improper points, lines vary drastically in length, and blank lines are often inserted.

You should include your name, call and packet address at the end of the text so that the person reading your message will be able to send a return message to you if he/she wishes to do so.

You complete the text with either a Ctrl C or these three characters: the "slash" (/) plus the letters "EX". These characters must be on a line by themselves. On some systems only the Ctrl Z will work. This tells the system that you've finished entering the message.

Messages that are going to be forwarded to several BBS's or across a long distance should be limited in size. Extremely long messages can tie up the forwarding system unnecessarily, so users are advised to break up long messages into parts, keeping them to a length of 2 - 3 K each

In this part we're going to look at the WHITE PAGES. No, not your local telephone directory, but the packet radio directory known as the "White Pages". You help supply the information for "WP", and you can also use it to find the home BBS, QTH, and zip code of your friends on packet.

"White Pages" was initially designed by Erich Williams, WD6CMU, of Richmond, California. Hank Oredson, WORDI, later added a WP database to his packet bulletin board software. It's a database of packet users showing their name, home BBS, QTH and zip code. It's updated and queried by packet message, allowing stations from all over the world to take advantage of it. As users enter their name, home BBS, QTH and zip code into the BBS user file, the software automatically assembles a message once a day containing all of the latest user information and sends it to AD8I in Ohio, now the national White Pages Server. Systems in Northern California also exchange this information. As a result, you can easily find the name, home BBS, QTH and zip code of other stations on packet all across the country using the White Pages database.

If your BBS is operating with its own WP database, you may make inquiries of it using the "I" command. Simply enter I followed by the callsign you'd like information about. If you wanted information on ZL1RAH, for example, you would enter: I ZL1RAH

Information from the WD8CMU or AD8I White Pages is obtained by sending a message to "WP @ AD8I.OH". Since the messages are read and answered by the WP software, not a person, you must use the correct format: <callsign> QTH? You may include as many requests as you wish in one message, but each request must be on a separate line. the last line of the message should be : DE <your_callsign> @ <Home_BBS> so that the response is returned to you at your home BBS. If the return address line is not given, the WP program will attempt to determine the originating station and BBS from the message headers. If the requested information is not available from the WP database, the return message will tell you so. Here's an example of a message sent to the WD6CMU or AD8I White Page Database:

(Your BBS prompt) W6BBS> SP WP @ WD6CMU.CA (SP WP @ AD8I.OH would be

Enter subject of message: Query used for the AD8I database)

Enter Text:

K9AT QTH?

WA6DDM QTH?

KC3XC QTH?

K3AKK QTH?

DE N6XYZ @ W6BBS

(Control Z)

Capital or lower case letters may both be used within the message.

Just like all other packet messages, messages addressed to WP are forwarded from BBS toward their destination. If a BBS operating with the WORLI WP Server handles a query message, it will respond with any pertinent information that it has available. As a result, you might receive more than one one response to your WP query. The WP program also collects data from any WP responses it sees, as well as from the headers of every message that passes through. The information on each call in a WP database is usually deleted in 60 to 90 days if it's not updated. This is determined by local sysops.

INTRODUCTION TO PACKET RADIO - PART 9 PAGE 18

It is important to note here that you should choose ONE BBS as your home BBS, the one where you want all your messages delivered. You should also make sure that it is a full service BBS, not a personal mailbox. Always enter that callsign when you are asked to enter your home BBS, even if you are using another system at the time. When a message arrives at the BBS destination given in the "@BBS column, some of the latest software will check the White Pages information to make sure that the message has been delivered to the right place. If it finds that a different BBS is listed as the addressee's home BBS, it will insert that BBS callsign in the message and send it on it's way. If you enter diferent home BBS calls on several BBSs, your mail could easily end up being sent fom BBS to BBS and never reach you. If you move or change your home BBS, you should then make sure that you update the information for your call in the White Pages database. Use the NH, NQ and NZ commands to update the information. Making sure that the information in the White Pages is correct will help to get your messages delivered to the correct BBS.

In this and the next part of the series we're going to take an in depth look at the packet node network. In part 4 of this series we explained how to use the network for connecting to another station. Now we'll look at the other features a node offers.

A packet node, in most cases, is still set up for digipeater operation, so you can still use it as a regular digipeater, but for most of your connections you'll want to use the node features. When using a string of digipeaters, your packets have to reach their destination parity correct, and the receiving TNC has to return an acknowledgement (ack) to your TNC for each packet cycle to be completed. As you add more digipaeters to the string, the chances of this happening become less and less. Other stations on the frequency and noise can be the cause of many retries. When using a node, however, your packets no longer have to reach their destination before acknowledgements are returned to your TNC. Each node acknowledges your packet as its sent along the way toward its destination.

Using the packet node network can make your operation time on the packet more enjoyable and it can greatly expand the area that you can reach. The network of NET/ROM, TheNet, G8BPQ and KAM nodes is expanding very quickly and now covers most of the country. The nodes are showing up almost daily. Thanks to all of these stations and the interconnecting links, you can now connect to stations in many far distant places using a low cost powered 2 meter rig. Some nodes are set up for cross-banding, and with the introduction of nodes on 10 meter fm, there's the possiblity of working a station just about anywhere.

If you've been monitoring lately, you might have seen the nodes in action. You might have wondered why they were sending all of those weird symbols like @fx/<~|. What you're seeing is the nodes communicating with each other and updating their node lists. You might also have noted callsigns with high numbered SSIDs, such as WB9LOZ-14, WA6DDM-15, W6PW-12, ect. The nodes change the SSID of all stations so that the packets sent via the network are not the same as those sent directly. If you were to use a node to connect to another station in the local area, there's the possiblity of your packets being received by this station both from you directly and from the node. If the call through the node wasn't changed, the TNCs involved would be totally confussed as it would appear that two stations were connecting using the same callsign. The node automatically changes the SSID using the formula 15-N, where N is your usual SSID. A call with -0 becomes -15, a-1 becomes -14, a -2 becomes a -13, ect.

The node network is very simple to use. As explained in part 4, to use the node network, you first connect to a local node. it should be one where you can connect direct with good signal strength. Once you've connected, you then have several options -- connect to another station within range of the node, connect to another node, connect to an associated BBS, obtain a list of nodes that are avialable, or check route and user status. On NET/ROM and TheNet nodes you can also answer or call CQ.

There are several comands available on your local node. All have CONNCT, NODES, ROUTES and USERS, and depending on the type of node you're using, you might also find BBS, BYE, CQ, INFO, PARMS or PORTS commands available.

TOP

CONNECT: The connect command (which can be abbreviated as C) is used just like you use the CONNECT command with your TNC. To connect to another local station using the node, simply enter C followed by the callsign. To connect to another node you can use either the callsign or the alias. For example, you can connect to W6AMT or you can connect to the alias SFO. Either will work.There's a special consideration when making connection from a node using the G8BPQ Packet Switch software. Since these nodes are capable of having several different frequencies connected to the one node, you have to indicate which frequency port you want to make your connection to. The PORTS command, abbreviated P, will give you a list of the ports availlable, such as this:

SF:WB9LOZ-2} PORTS

1 144.99 Mhz

2 223.52 Mhz

3 443.15 Mhz

You then insert the port number between the C and the callsign, such as C 1 W6RFN, to indicate which frequency you want to use, in this case the port 1 frequency of 144.99 Mhz.

NODES: The NODES command has another feature that gives you a simple way to find out if another node is accessible and, if it is, the best route to use to reach it. It's easy to make a quick check of the route quality to any other node. All you need to do is enter N followed by either the alias or callsign of the node that you want to reach, such as:

N FRESNO or N W6ZFN-2

You'll receive a report showing up to three routes to the node you asked about, how good these routes are and how up to date the information is. If there is no information available, you will receive either "Not Found" or the complete node list, depending on the type of node or switch you're using.

Let's take a look at a typical report you would receive after entering N FRESNO. If you were connected to a NET/ROM or TheNet node the report would look like this:

SFW:W6PW-1} Routes To: FRESNO:W6ZFN-2

105 6 0 WB9LOZ-2

78 6 0 WW6L-1

61 5 0 WA8DRZ-7

If you were connected to a G8BPQ packet switch you would see one less column in the report and it would look like this:

SF:WB9LOZ-2} Routes To: FRESNO:W6ZFN-2

> 126 6 W6PQ-10

61 3 WW6L-1

60 4 W6PW-1

Each line is a route to the node you asked about. The symbol > indicates a route that's in use. The first number is the quality of the route. 255 is the best possible quality and means a direct connect via hard wire to a co-existing node at the same site; zero is the worst, and means that the route is locked out. 192 is aboute the best over the air quality you'll find, and it usually means that the node is only one hop away. If you see a quality of less than 80, you'll probably have a difficult time getting any information through via that route. The second number is the obsolescence count. This number is a 6 when the information for this route is less than an hour old. For each hour that an update on the route is not received, this number is decreased by one. A 5 means the informations is an hour old, a 4 means thats it's two hours old, and so on. The next number, shown only on NET /ROM and TheNet nodes, indicates the type of port. A 0 is an HDLC port; a 1 is an RS232 port. you don't need to pay any attention to this figure. The callsign is that of the neighboring node that's next in line on the route. Digipeaters are shown if any used to reach this neighboring node.

INTRODUCTION TO PACKET RADIO - PART 11 PAGE 21

This quick check on a node that you want to reach can save you a lot of time. You'll know immediately whether or not the node is available, and if it is, how good the available routes are to it. You then won't have to spend time trying to connect to a node that isn't available or is of poor quality. If you find that there's a decent route to the node or switch you want to reach, it's normally best to let the network make the connection for you. Simply enter a connect to the alias or callsign you want rather than connecting to each individual node along the route yourself.

If a route exists but the quality is not very good, you might want to connect to the neighboring node shown for the best route, then do another quality check, repeating this procedure until you find a route with decent quality. You can actually get through some distant nodes using this method if you have the time and patience to work on it.

ROUTES: The ROUTES command (abbreviated as R) will give you a list of the direct routes available from the node you're using to the other nodes. These are the nodes seen directly by the node you're using. The quality of each route is shown along with obsolescence count, as explained above. Any route marked with an exclamation point (!) means that the route values have been entered manually by the owner of the node and usually means that the route is not reliable for regular use.

USERS: The USERS command (which can be abbreviated as U) will show you the calls of all the stations using the node you're connected to. There are five descriptions used by the node to describe how users are connected:

UPLINK: The station indicated is connected directly to the node.

DOWNLINK: The node has made a connection from the first station to the second station. Example: DOWNLINK (K9AT-15 N6UWK) would mean that the node connected to N6UWK at the request of K9AT.

CIRCUIT: Indicates that the station has connected from another node. It shows the alias and call of the other node prior to the user's call. Example: (SFW:W6PW-1 WA6DDM) would mean that WA6DDM is using this node, but he connected to it from the SFW:W6PW-1 node.

CQ: See "CQ" below

HOST: The user is connected directly from the node terminal. This is seen when the owner of the node is a user, or the BBS associated with the node is using it to forward messages.

CQ : The CQ command (which cannot be abbreviated) is used for calling CQ, and it also can be used for replying to the CQ of another station. The CQ command is available only in the latest version of NET/ROM and TheNet.

Using the CQ Command: The CQ command is used to transmit a short text message from a node, and is also to enable stations that receive the transmission to connect to the station that originated it. The command is entered as: CQ [textmessage]

The "textmessage" is optional and can be any string up to 77 characters long (blanks and punctuation are allowed). in response to a CQ command, the node transmits the specified textmessage in "unproto" mode, using the callsign of the originating user with a translated SSID as the source and "CQ" as the destination. For example, if the user station W6XYZ connects to a node and issues the command: "CQ Anybody around tonight?", the node would then transmit "W6XYZ-15>CQ: Anybody around tonight?"

After making the transmission in response to the CQ command, the node "arms" a mechanism to permit other stations to reply to the CQ. A station wishing to reply may do so simply by connecting to the originating callsign shown in the transmission (W6XYZ-15 in the example above). A CQ command remains "armed" to accept replies for 15 minutes, or until the originating user issues another command or disconnects from the node.

INTRODUCTION TO PACKET RADIO - PART 11 PAGE 22

Any station connected to a node may determine if there are any other stations awaiting a reply to a CQ by issuing a USERS command. An "armed" CQ channel appears in the USERS display as: (Circuit, Host, or Uplink) <~~>CQ(usercall).

The user may reply to such a pending CQ by issuing a CONNECT to the user callsign specified in the CQ(...) portion of the USERS display -- it is not necessary for the station to disconnect from the node and reconnect.

Here's a typical transmission would look like: (* = entered by user)

* cmd: c KA6YZL-1

cmd: ***Connected to KA6YZL-1

* USERS

501sjc:KA6XYZ-1} NET/ROM 1.3 (669)

Uplink(WB9LOZ)

Uplink(K1HTV-1) <~~> CQ(K1HTV-14)

Circuit(LAS:K7WS-1 W1XYZ) <~~> CQ(W1XYZ-15)

Uplink(N4HY)

* CONNECT W1XYZ-15

501SJC:KA6YZS-1} Connected to W1XYZ

* Hello! This is George in San Jose

Hi George! Tanks for answering my CQ. ect.

Users of the CQ command are cautioned to be patient in waiting for a response. your CQ will remain"armed" for 15 minutes, and will be visible to any user who issues a USER command at the node during that time. Wait at least five minutes before issuing another CQ to give other stations a chance to reply to your first one!

BBS: The BBS command is available on nodes using G8BPQ software where an associated packet bulletin board system is operational. Entering BBS will connect you to the associated BBS.

BYE: The BYE command is available on G8BPQ nodes and is used for disconnecting from the node. It does the same thing as disconnecting.

IDENT: The IDENT command, found on NET/ROM nodes, will give you the identifcation of the node you're using.

INFO: The INFO command, found on TheNet and G8BPQ nodes, will give you information about the node, usually the alias, callsign and location.

PARMS: The PARMS (Parameters) command, found on NET/ROM nodes, is for the owner's use in determining how his station is working.

TOP

The National Traffic System, known as NTS, is the ARRL sponsored Amateur Radio message handling network. Packet radio is now playing a very important part in the network. Packet Radio is now playing a very important part in the network, so let's take a look at the system and give you some tips on handling NTS traffic by packet.

Handling third party traffic is the oldest tradition in amateur radio. Nationwide, the National Traffic System has hundreds of local and section nets meeting dialy in order to facilitate the delivery and origination of such messages. More and more of this traffic is being originated, relayed, and delivered on packet. I you enjoy traffic handling, you can easily get involved in NTS via packet. If you're on packet but know nothing about NTS, this part of the series will get you off to a good start. At the end you'll also find some references for further information on NTS.

Local packet BBSs have to be checked daily for traffic that needs to be delivered or relayed. When you check into your local BBS, enter the LT command, meaning "List Traffic". The BBS will sort and display a list of all NTS traffic awaiting delivery. It'll look similar to this example:

7893 T 486 60625 KB6ZYZ NTSIL 1227/0712 QTC1 CHICAGO, IL 312-267

7802 T 320 06234 K6TP NTSCT 1227/0655 QTC1 NEW HAVEN, CT

7854 T 588 93432 KA4YEA 1227/0311 QTC1 CRESTON, CA 93432

7739 T 412 94114 KK3K 1227/0311 QTC1 San Francisco 415-821

7781 T 298 94015 W1KPL 1226/2356 QTC1 DALY CITY, CA 415-992

You might see traffic that is being relayed by your local BBS to some other part of the country as well as traffic for your local area. The "Subject" or "Title" column of the listing will show the destination of the traffic. If you see a message that is within your local area, help out and deliver it.

RECEIVING A MESSAGE: To take a message off of the Bulletin Board for telephone delivery, or for relay to a local NTS net, enter R followed by the message number. Using the listing above, R 7839 would send you the message from KK3K for San Francisco. You'll find the message in a special NTS RADIOGRAM format, with a preamble, address, telephone number, text and signature, ready for delivery. After the message has been saved to your printer or disk, the message should erase from the BBS. you use the KT command, which means "KILL TRAFFIC", followed by the message number. In this case you would enter KT 7839 to erase the message you took from the BBS. This prevents the message from being delivered again to someone else.

DELIVERING OR RELAYING A MESSAGE: Once you have received the NTS Radiogram, it should, of course, be handled expeditiously. If it's for your immediate area, you should deliver the message by telephone. if you took the message for delivery to the local traffic net, you should make an effort to see that it gets relayed as quickly as possible.

SENDING MESSAGES: Any amateur can originate a message on behalf of another individual, whether the person is a licenced amateur or not. It is the responsiblity of the originating amateur, however, to see that the message is in proper form before it's transmitted. A special format is used for NTS traffic so that the messages are compatible across the entire network. Each message should contain the following components in the order given:

number, precedence, handling instructions (optional), the station of origin, check, place of origin, time filed,date, address, telephone number, text and signature.

When the message is ready to be entered into your local BBS, you must use the ST command, which means "Send Traffic", followed by the zip code of the destination city, then @ NTS followed by the two letter state abbreviation.The form used is:

ST ZIPCODE @ NTSxx.

INTRODUCTION TO PACKET RADIO - PART 12 PAGE 24

In this part of the series we'll take a look at many of the TNC commands available to you that we haven't in previous articles. We will be discussing the commands used in the TAPR, TNC2 and TNC2 clones. You might find that some of the commands are not available in your particular TNC or that they're used in a slightly different manner than the one explained here. Please refer to your owners operating manual for specific details on how to use these commands in your TNC.

8BITCONV: This command enables the transmission of 8-bit data in converse mode. Used with AWLEN - see below. For normal packet operation, such as keyboard to keyboard transmissions, use of bulletin boards, and transmission of ASCII files, 8BITCONV should be OFF. If you need to transmit 8-bit data, set 8BITCONV ON and set AWLEN to 8. Make sure that the TNC at the receiving end is also set up this way. This procedure is normally used for transmission of executable files or a special non-ASCII data set.

AWLEN: This parameter defines the word length used by the serial input/output port of your TNC. For normal packet operation, as described above, AWLEN should be set to 7. Set to 8 only if you're going to send 8-bit data.

AX25L2V2: This command determines which level of AX.25 protocol you're going to use. If OFF, the TNC will use AX.25 Level 2, Version 1.0. If ON, the TNC will use AX.25 Level 2, Version 2.0. NOTE: Some early TNCs will not digipeat Version 2.0 packets. With AX25L2V2 OFF, if your TNC sends a packet and the packet doesn't get acknowledged the first time it was sent, it will send it again and again, until an "ack" is received or the TNC retries out. With AX25 ON, if your TNC sends a packet and doesn't receive an "ack" the first time, it will send a poll frame to see if the other TNC received the packet. If yes, then it will continue, if not then it would send the last packet again. The advantage here is that short poll frames are sent, rather than long packets containing data. This can greatly reduce channel congestion. For VHF/UHF operation, it is almost essential that every TNC have AX25L2V2 ON. Many operators have suggested that Version 2.0 NOT be used on the HF bands as it tends to clutter the frequency with poll frames. See the CHECK command below for related information.

BEACON: Used with EVER or AFTER to enable beacon transmissions.

BEACON EVERY n - send a beacon at regular intervals specified by n.

BEACON AFTER n - send a beacon once after a time interval specified by n having no packet activity.

n = 0 to 250 - specifies beacon timing in ten second intervals.

1 = 10 sec's; 2 = 20 sec's; 30 = 300 sec's or 5 minutes

For example, if you set BEACON EVERY 180 (BE 180), the TNC will transmit a beacon every 30 minutes. If you set BEACON AFTER 180 (BA 180), the TNC will transmit a beacon after it hears no activity on the frequency for 30 minutes. BE 0 will turn the beacon off. The text of the beacon is specified by BTEXT and can contain up to 120 characters. The path used for the beacon transmssion is specified by the UNPROTO command. YOU SHOULD USE BEACONS INTELLIGENTLY! Beacons are often a point of controversy in the packet community because they tend to clutter the frequency if used too frequently. You should keep your beacons short and frequent, and they should only be used for meaningful data. Bulletin boards use the beacon for advising the community of who has mail waiting for them, clubs use beacons for meeting announcements, beacons are used for weather warnings, ect.

INTRODUCTION TO PACKET RADIO - PART 13 PAGE 26

CHECK n: Sets a timeout value for a packet connection. Operation depends on the setting of AX25L2V2. The value of CHECK (n) determines the timing. Value may be 0 to 250. Check set to 0 disables the command. If a connection between your station and another exists and the other station seems to "disappear" due to changing propagation or loss of an intermediate digipeater, your TNC could remain in the connected state indefinitely. If the CHECK command is set to a value other than 0, the TNC will attempt to recover. The setting of AX25L2V2 will determine what action is taken. If AX25L2V2 is ON, the TNC will send a "check packet" to varify the presence of the other station if no packets have been heard for n * 10 seconds. If a response is received, the connection will remain. If no response is received, the TNC will begin the disconnect sequence, just as if the DISCONNECT command had been sent. If AX25L2V2 IS OFF , after no packets are heard for n * 10 seconds, the TNC will not send a check packet, but will begin the disconnect sequence.

CMSG: Enables the automatic sending of a connect message when ever a station connects to your TNC. If CMSG is ON, the TNC will send the message contained in CTEXT as the first packet of the connection. CTEXT can contain up to 120 characters. This feature is often used when the station is on but the operator is not present. The connect message is used to advise the other station of that fact, and often says to leave a message in the TNC buffer. If CMSG is OFF, the text message is not transmitted.

KISS: KISS enables the TNC to act as a modem for a host computer, allowing programs such as TCP/IP, the G8BPQ Packet Switch, various BBS programs, and other programs using the Serial Link Interface Protocal (SLIP) to be run. Before turning KISS on, set the radio baud rate and terminal baud rate to the desired values. Set KISS ON and then issue a RESTART command.

MAXFRAME: Sets the upper limit on the number of unacknowledged packets the TC can have outstanding at any time. (The outstanding packets are those that have been sent but have not been acknowledged.) It also determines the maximum number of contiguous packets that can be sent during one transmission. Value can be set from 1 to 7. The best value of MAXFRAME depends on the frequency conditions. The better the conditions are, the higher the value you can use. If conditions are poor due to the amout of traffic on the frequency, noise,or other variables, (shown by lots of retries) MAXFRAME should be reduced to improve throughput. The best value of maxframe can be determined through experimentation. MAXFRAME of 1 should be used for best results on HF packet.

MFILTER: This command allows you to enter up to four ASCII character codes, 0 - $7F, for the control characters that you want eliminated from your monitored packets. Codes may be entered either Hex or Decimal. Here are the ASCII codes for some of the more troublesome control characters found in monitored packets:

HEX DEC FUNCTION POSSIBLE RESULT

$07 07 Control G Rings your bell or "beep" your speaker

$0C 12 Control L Form Feed - could clear your screen

$13 19 Control S Can cause your screen to stop scrolling

$1A 26 Control Z Can clear your screen

$1B 27 Escape Can cause your cursor to move to a random point on your screen and can raise havoc with the printer control.

AEA has added a new code, $80, that will not allow ANY control characters to be displayed on the user's screen from monitored packets.

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Here are some tips to help make your packet operating more enjoyable. Whether it's while making local QSO's, checking into a BBS or mailbox, or working DX, there are a few things you should take into consideration that will help eliminate problems and waiting time and will increase your throughput. ("Thoughput" is a word that has come into use by packet operators that means the amount of usable packet information received by the distant station.)

When connecting to another station, don't use a digipeater or a node unless you have to. Each digipeater you add to the path increases the time required to get your signal to its destination and get an acknowledgement returned. It also increases the chance for interference and for collisions with other packets. You'll be amazed at the difference in throughput when comparing a direct connect to one with just one digipeater in the path.

The packet node network, as we discussed in previous articles in this series, does a great deal to help you get your packets through, but you must remember that throughput there, too, is affected by the number of nodes and the conditions between you and the destination station. The big adantage of the nodes is that the acknowledgements do not have to return all the way from the destination station. Packets are acknowledged from node to node, so that eliminates a large part of the problems encountered. Getting the original packet through, however, remains to be much of a problem for the nodes as it is for when using digipeaters. It can take several minutes to get a packet through when you're working a station some distance away.

Dr. Tom Clark, W3IWI, has determined that for each HOP in a packet path the loss of packets can vary from 5% to 50% depending on the amount of traffic. Remember, each node adds a hop, so multiply those percentages by the number of hops, then multiply by 2 to account for the acknowledgement, and you can see how quickly the path deteriorates as traffic increases and digipeaters and nodes are added to it.If you have a choice, use a frequency that doesn't have a lot of other traffic on it. It makes sense that more stations there are on frequency, the more chances there are for collisions and retries. A path that will work perfectly without a lot of traffic, can become totally useless under heavy traffic conditions. Just one additional station on the frquency can decrease throughput by about half in many cases. Another consideration, especially if working over a long distance, is atmospheric conditions. You might not have experienced this before on VHF, but with packet's high sensitivity to noise, a slight change in signal strength can mean the difference between getting your packets through or not getting them through. An example of one path that is very vunerable to conditions due to its distance is from W6AK-1 on Mt. Vaca to WB6AIE-1 on Bald Mountain in Yosemite National Park on 145.05 Mhz. Most of the time, packets go between these two nodes without any problem, but there are times, especially when it's a hot summer day in the Sacramento Valley, when it's impossible to get a packet from one to the other. In the Bay Area, the fog has a drastic affect on VHF signals. When a fog bank is moving in off the Pacific, it can act as an excellent reflector. Signals that are not normally heard can reach signal strengths of 40 and S9.

Multipath is another problem that can greatly affect your packet signal. Multipath is the term used to describe the receipt of multiple signals from one source due to reflections off of buildings, hills, or mountains. The "ghost" in a television picture is a form of multipath. A station with a very strong signal into a digipeater or node often cannot use that path if multipath causes the signal to be destorted. Each packet is checked for 100% accuracy and is not acknowledged unless it is. Multipath reflection can cause occasional bits to be lost so you end up with multiple retries and a poor path even with strong signals.

To sum up, for best results on VHF use the least number of digipeaters and nodes as possible, use a frequency with low activity, and be aware of atmospheric conditions and multipath problems.If you use packet on HF, remember to change your transmit baud rate to 300 and to use a short PACLEN (a value of 40 seems to work quite well) and a MAXFRAME of 1. The chances of getting a short packet through the noise and QRM are much better than for a long one.

In this article, lets do some reviewing. I'm going to present a short quiz on packet, covering the basics that I've presented in the past 15 parts. Let's see how well you can answer the following questions without looking back at the past articles. In part 17 I'll discuss each question and give you the correct answers.

1. What are the three TNC modes of communication?

a) Connect, Converse, Terminal

b) Command, Converse, Terminal

c) Command, Converse, Transparent

d) Command, Connect, Transparent

2. What TNC command is used to set the transmit path for beacons and CQ's?

3. What is the TNC command CHECK used for?

4. While you're connected to another station, what command is used to monitor other traffic on the frequency?

5. If you saw one of the following lines on your screen when in monitor mode, what would the asterisk indicate?

ZS1RAH>ZS0STB,ZS1IT*:HI GERT

6. Why does the packet node network improve communications?

7. If you're connected to a station in New Mexico using the node network, how do you disconnect?

8. If N6ZYX-2 connected to you via a node, what would the SSID of the station become at your end of the connection?

9. When you're connected to another station, what are the two most probable causes for packets not to be received by the other station?

10. There are several basic commands used on a packet bulletin board system. Indicate what you would enter to perform the following:

a) Receive a list of messages.

b) Download a file in the General (ID G) directory called FCCEXAMS.89

c) Enter a private message to JIM, WA6DDM, who uses the W6PW BBS in San Francisco, California.

d) Read message 7134 with complete forwarding headers.

e) Find out what stations have been have been heard by the BBS on port B.

11. To send an NTS message via packet addressed to Tom Smith, 123 Main Street, Keene, NH 034311, telephone (603) 555-4321, what would you enter at the BBS prompt?

12. If a message has a STATUS of BF, what does that indicate?

13. If you received a message from a friend in Chicago that had been forwarded to your home BBS through four other BBS's and the message had a Date/Time of 0316/2245 when you listed it, which of the following is a TRUE statement?

a) The message was written at 2:45pm on March 16.

b) The message was entered into the BBS by your friend at 22:45 on March 16.

c) The message was forwarded by your friends BBS in Chicago at 22:45 on March 16.

d) The message was received at your home BBS at 22:45 on March 16.

14. If you wanted to send a message to your friend John,W4IP, but you didn't know what the call of his home BBS was, what could you do to try and find out what the call is?

15. What is the maximum value for Maxframe? If you're working a station on 30 meters and are sending a lot of retries, should you increase or decrease Maxframe?

Well, how did you think you did? We'll take a look at the answers to these questions and more in part 17.

How did you do in the review quiz in the previous part of this series? If you haven't taken it, you might want to read part 16 and take the quiz now before reading any further.

Here are the correct answers and the series part numbers where you can read more about the subject.

1- Answer C is correct. The three TNC modes of communication are Command, Converse and Transparent. Command mode is for communicating with the TNC. The Converse mode is for QSO's, connects to a BBS or mailbox, etc. and Transparent mode is used for binary file transfer. (Parts 2, 3 and 14)

2- The UNPROTO command is used for setting the transmit path for both beacons and CQs. (Parts 3 and 13)

3- The CHECK command is used for setting a timeout value in your TNC.If set to a value other than zero, the TNC will attempt to recover a connection after a certain specified time if nothing is received from the other station. This command is used in combination with the AX25L2V2 command. (Part 13)

4-The MCON command (Monitor while CONnected) is used to monitor other traffic on the frequency while you're connected to another station. (Part 3)

5- When monitoring, the asterick indicates the station that you actually hear the packet from. The MRPT command must be ON for the monitor display to show digipeaters. (Part 2 and 3)

6- The packet node network improves communications because packets are acknowledged from your station to the first node, and then node to node to the destination. A packet doesn't have to reach the destination before an ack is returned. (Parts 4, 10 and 11)

7- When using the node network (no matter who you're connected to) you disconnect by going to command mode on your TNC and entering a "D", just like at other times. The fact that you're using several nodes or are connected to a distant station makes no difference. The network will take care of disconnecting all stations and links. (Parts 4, 10 and 11)

8- N6ZYX-2 would appear as N6ZYX-13 if he connects to you using a node. The nodes change the SSID using the formula 15-N. (Part 10)

9- The two most probable causes for a packet not to get through are collisions with other packets on the frequency and noise due to weak signals. (Part 15)

10- BBS commands:

a) To receive a list of messages: enter L

b) To download a file in the General (G) dir called FCCEXAMS.89, you'd enter: DG FCCEXAMS.89

c) To enter a private message to Jim, WA6DDM : SP WA6DDM @ W6PW.CA

(The @ W6PW would not be needed if you were using the W6PW BBS.)

d) To read message 7134 with headers: RH 7134

e) To find out what stations were heard on port B of the BBS: enter JB

(Parts 5, 6, 7 and 8)

INTRODUCTION TO PACKET RADIO - PART 17 PAGE 31

11 - If you wanted to send an NTS message to Tom Smith, 123 Main St, in Keene, NH 03431, you would enter the following at the BBS prompt > st 03431 @ NTSNH (Parts 6 and 12)

12 - A message with a STATUS of BF means that the message is a bulletin and that it has been forwarded to all stations that are supposed to receive it from the BBS you're using. (Part 8)

13 - Answer D is correct. The date/time shown on a message when it's listed is the time the message was received at the BBS you're using. Please note that the date/time of a message indicates whatever time the BBS you're using, is set to, and that could be local time or zulu time, UTC, GMT, or whatever. Most BBSs are now set to zulu time (UTC, GMT), but a few still use local time. When you read a message, you should be able to read the date and time the message was written from the message header. (Part 8)

14 - To find the call of the home BBS of your friends, use the White Pages Directory. If the BBS you're using has the WP feature enabled, you will find the I command to be useful, otherwise send an inquiry to WP. (Part 9)

15 - The maximum value for MAXFRAME is 7. Maxframe is the number of packets transmitted by your TNC contiguously, and the number of unacknowledged packets the TNC can have outstanding. You decrease Maxframe when the conditions are poor. Your TNC will send fewer packets at one time, so there will be less information to collide with other packets on the frequency and less chance of information being wiped out by noise. (Part 14)

There is no passing grade on the quiz. It was designed for you to check your general packet knowledge, and you'll have to be your own judge of that. I hope you did well on it!!

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In the previous 17 parts of this series, I have attempted to cover all of the basics of packet radio - from setting up your TNC and making your first QSO, to using digipaters, the packet node network, bulletin board systems and mailboxes. Many of the TNC commands have been explained, including the best settings for normal packet use, and I've offered suggestions that should make it easier and more enjoyable for you to use packet radio.

Changes in packet are made quite frequently as new versions of the software for the TNC, node network and bulletin boards are released. Try to be aware of these changes so that you can take advantage of the latest information.

Now you might want to investigate some of the newer developments in packet radio. There are several programs available for making special use of packet, such as the Packet Cluster software used by the DX Spotting Networks, TCP-IP, Tex-Net, Conference Bridging, etc. Pac-Sat, the packet satellite program, is growing in popularity as more satellites carrying packet radio equipment are released. High speed modems running at speeds of up to 56 kilobaud are just around the corner for general use. You'll find a wide variety of special interests avialable to you.

I'd like to thank the following for help in preparing this series:

Don Simon, NI6A

Bill Choisser, K9AT

Don Fay, K4CEF

Scott Cronk, N7FSP and

Hank Oredson, WORLI

If you have any comments on this "Introduction to Packet", or if you have any questions on the topics discussed, want to suggest new topics for inclusion in future articles, or want to correct or update any of the information contained in the series, please send a packet message to me. Your comments will be appreciated. I hope that you've found the series to be informative and helpful in making packet more enjoyable for you.

73, Larry Kenney, WB9LOZ @ W6PW.#NOCAL.CA.USA.NA