Using Repeaters

 

What is a repeater? And why use it?

The most basic form of repeater receives communication on one frequency and re-transmits at a different frequency. This is known as duplex communication.

Why is this useful?

  • You can greatly increase the range of your handheld or mobile radio. Repeaters are usually set up at high locations with good quality antennas and higher transmit power than your device.
  • Repeaters can be physically or remotely linked to other repeaters. With different kinds of links, you can reach an entire metropolitain area, or even across the world through repeater-to-repeater Internet links.

Repeaters are generally set up to operate with FM modulation on the amateur bands within  the  VHF (30 MHZ – 300 MHZ) and UHF frequencies (300 MHZ – 3 GHz). These are generally the frequencies used by handheld and mobile devices.

Who’s allowed to set up a repeater?

In Canada, there is one legal and one practical requirement.

  • You must have your amateur radio advanced license
  • There must be an available repeater frequency within the band.

Each repeater has a unique call sign and transmit frequency assigned.

How and why is access controlled?

Access to repeaters is controlled by an inaudible tone called a CTCSS or PL tone.

A repeater only repeats if it detects the tone. This prevents the receiver from constantly transmitting background noise that may be at a high enough level to trigger transmission. Constantly transmitting on a frequency is illegal, so this saves everyone a lot of grief and unnecessary power usage.

Most repeaters are configured to time out after a reasonable amount of talk time. 3 minutes is pretty common. This is to stop someone from yabbering on. Repeaters are meant to be shared.

Configuring a radio for repeater usage

Most UHF/VHF radios can be configured or pre-programmed for repeater usage.

There are three things you need to know:

  • The repeaters’s transmit frequency. Any time a repeater’s frequency is documented, it is invariably the frequency at which the repeater transmits. You always listen first so you know if anyone else is transmitting.
  • The repeater’s receive frequency offset. This could be a specific frequency, but is generally expressed as an offset. Typical values are:
    • VHF: – 600 KHZ. Sometimes shown as 0.6 MHz
    • UHF: + 5 MHZ
  • CTCSS Tone: The CTCSS tone (also referred to as PL tone) required to enable retransmission. Sometimes shown
  • Modulation. This is generally FM, but can be SSB for repeaters operating in the HF range (3 to 30 MHz)

When your radio is properly configured for the repeater, it will:

  • (1) listen on the repeater’s transmit frequency
  • (2) automatically shift to the repeater’s receive frequency when you transmit
  • (3) automatically add the CTSS tone when you transmit.

Consult your radio documentation for how to configure it for repeater operation. On most modern radios, you can program in presets for multiple repeaters. We have examples in our Baofeng UB-B6 user guide  for how to do it manually , and how to do it with radio programming software.

Linked Repeaters

Some clubs have multiple repeaters linked together. Whatever is transmitted to one repeater is sent out from all the other repeaters.  The repeaters are usually linked by radio using directional antennas, but other connection types like Internet are possible. For emergency preparedness and disaster planning purposes, radio links are preferred.

The London, Ontario Southern Ontario Repeater Team has a great site with a diagram of how it’s done.  They also list different “Net” times where groups meet on the repeater for different purposes.

York Region Amateur Radio Club’s  Repeater Page  lists their linked repeaters. They are included in our radio programming sample file.

Finding  repeaters in your area

A simple google search where you specify your geographic area with  will usually turn up several options.

Web site Repeater Book is a great example where you can search for repeaters around the world. It’s well documented, and if you click on the frequency link for a repeater, it will list information like:

  • Repeater status
  • Web site for the repeater
  • Linked repeater information

Talking on a repeater

Repeater basic protocol and manners

  • Avoid radio jargon and code words. Proper etiquette for repeaters is to not use Q codes (or even worse, 10-codes) or other jargon.
  • Identify yourself as required by ham radio rules – at start at end of the conversation, and at least every 30 minutes in between.
  • Remember that your communication may be going a long way and *everyone* can hear you. If repeaters are linked, you could be covering
  • Don’t be afraid to identify yourself as a beginner. Ham operators are generally very courteous and love to help.
    • In the examples below, we use:
      • callsign VA3NUB (newbie!). You should use your own.
      • frequency 123.456. Identify the frequency and/or call sign of the repeater before you start. It’s good to know and to inject into your intro because in the case of linked repeaters, it identifies which one you are on.
  • Verify that you are allowed on the frequency. If you have a Basic license (in Canada),  you are not allowed to transmit below 30 MHz or to use a repeater or set of linked repeaters that transmit below 29.5  MHz. The exception to 29.5 MHz for repeaters is because you may be listening at 30 MHz (or just above), and the standard frequency offset for repeaters in the VHF 2m band is -600 KHz.
  • Keep it short. Don’t blabber on. Give other people a chance to join in or respond.
  • Don’t kerchunk the repeater. Many repeaters will transmit a beep when you finish transmitting. Some users will hit the transmit button as a test just to hear the beep. That’s called kerchunking, and it’s bad behaviour. Always state your call sign, with something like  “VA3NUB testing”
  • There’s lots more on this page and others.

A simple repeater session

  1. Listen to see if anyone is else is talking. There may be a net or other conversations already happening.
  2. Start with
    • “VA3NUB listening”
    • Better: “VA3NUB listening on 123.456″. Because you could be on one of a set of linked repeaters.
    • Best: user the repeater call sign and frequency
      • “VA3NUB listening on YRARC 123.456”
  3. If nothing back, wait 10 seconds and repeat step 2
  4. If someone answers, acknowledge it.
    • If you didn’t hear their call sign, ask them to repeat
      • “This is VA3NUB. Can you repeat your call sign?”
        • The other person will usually acknowledge your call sign and repeate his.
    • When you hear their call sign, acknowledge it
      • VA3HAM, this is VA3NUB. My name is George
  5. Simple conversation starters:
    • I’m testing my radio and repeater connection. How are you receiving me?
    • I’m new to this. I would appreciate any feedback on my radio usage.
    • I’m located in Thornhill. What’s your location? (Note: ham operators will use QTH for location. Be polite, but try to avoid jargon/Qcodes)
    • What equipment are you using?
  6. Closing up the conversation.
    • “VA3NUB  clear”. Or “VA3NUB out”

Long range repeater links: IRLP

The Internet Radio Linking Project (IRLP) allows you to create temporary links between IRLP repeaters around the world. Repeater operators connect the necessary hardware between their repeater and the Internet and obtain a unique IRLP code for their repeater. It was started in Vancouver, Canada and the first node number 1000 is still active.

You can set up and drop an IRLP connection between repeaters by sending DTMF (dual-tone multi-frequency) signals. DTMF is the fancy technical name for the  tones generated by a touch tone telephone.  Most UHF/VHF radios and handhelds have tone generating capability from their keypad. One of our radio user guide pages on DTMF has an example of how this works. There are also smartphone apps that will play the tone into your radio’s microphone.

Finding IRLP repeaters and checking status

The  best place to look for repeaters is on the IRLP repeater search page.

  1. Start by finding a repeater close to you, searching by country and province, and then down to city. Check it’s status to ensure it is available.
YRARC Repeater IRLP Status from IRLP.net

Note the Node ID and call sign, and the status of IDLE.

Remember that only one IRLP connection is active at a time from a repeater. If the IRLP connection is active, you will see a node number instead of IDLE.

IMPORTANT: Not all repeaters on a set of linked repeaters are IRLP repeaters! As an example, YRARC’s repeater page shows multiple linked repeaters, but only VE3YRC is configured for IRLP. That’s why it’s the only one that shows up on the IRLP search page.

2. Find a repeater to connect to.

Same search as above. Look for an IDLE repeater and note the call sign and node number.

A simple IRLP link session.

All the same protocol and etiquette of a simple repeater session apply – and more. Remember that you are now linking all the traffic from the two repeater sites. Everything on one side will be repeated on the other, and that includes any linked repeaters at each site.

The following example is for a session:

  • From: repeater VE3YRC, IRLP node 2920 in Aurora, Ontario
    • Make sure you set up the repeater on your radio with the appropriate frequency, offset and CTCSS tone.
  • To: repeater VE7RHS, IRLP node 1000 in Vancouver, BC
  1. Listen to see if anyone is else is talking. There may be a net or other conversations already happening.
  2. Start with
    • “VA3NUB listening”
    • Better: “VA3NUB listening on 123.456″. Because you could be on one of a set of linked repeaters.
    • Best: user the repeater call sign and frequency
      • “VA3NUB listening on YRARC 123.456”
  3. If nothing back, wait 10 seconds and repeat step 2
  4. If someone answers, acknowledge it and request permission to run the link. If nobody answers, jump to step 5.
    • If you didn’t hear their call sign, ask them to repeat
      • “This is VA3NUB. Can you repeat your call sign?”
        • The other person will usually acknowledge your call sign and repeate his.
    • When you hear their call sign, acknowledge it – and
      • VA3HAM, this is VA3NUB. My name is George. I want to test an IRLP link. Do you mind if I do this for a few minutes?
  5. Announce what you are doing
    • “This is VA3NUB testing IRLP connection to VE7RHS node 1000 in Vancouver, Canada:”
  6. Enter the DTMF tones for the connection – in this example, 1000.
  7. Listen for an acknowledgement from the remote connection. Most IRLP repeaters will automatically play an announcement when connected or disconnected.
  8. You can also check the IRLP repeater search page for the connection status. Check it both on your local repeater connection and the remote repeater. You may need to wait a minute or two and refresh the page.
  9. Announce the connection
    • “This is VA3NUB listening. Testing IRLP connection from node 2920 in Ontario Canada to VE3RHS node 1000 in Vancouver, Canada.”
    • If nobody answers, wait 10 seconds and repeat
    • If someone answers, carry on a conversation.
    • If your conversation carries on for more than 30 minutes, remember to repeat your call sign.
      • “This is VA3NUB on IRLP connection from IRLP node 2920 in Ontario Canada to VE3RHS node 1000 in Vancouver Canada
  10. Closing up the connection
    • Announce it.
      • “This is VA3NUB closing IRLP connection to VE3RHS node 1000. Clear.”
    • Close the connection by entering DTMF tones 73
    • Listen for the connection closing announcement. If you don’t hear it:
      • Check the web site for status and repeat the 73 if necessary.
      • If you don’t have access to the web site, enter the 73 a second time as a precaution.
    • If you are done:
      • “VA3NUB  clear”. Or “VA3NUB out

 

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