Repeaters and Linking Presented by Rob Ewert VE1KS Repeaters and - PowerPoint PPT Presentation

Repeaters and Linking Presented by Rob Ewert VE1KS

Repeaters and Linking \ Introduction /  My Background  Repeaters • What are they? • Why do we need them? • How do they work? • How are they controlled • What kinds are there? • Where are they? • What do I need to know to use them • Digital Voice Modes  Linking Repeaters • Why do we do it? • How do we link repeaters? • How are links controlled • Linking in NS (MAVCOM, IRLP, Echolink)  Operating Etiquette • Repeater usage etiquette • Linking etiquette

Repeaters and Linking \ Repeaters /  What are they? • They re-transmit, in real time, any signal received • Antenna, duplexer, receiver, transmitter & controller • Some times multiplexers are used instead of duplexers • Coverage is usually circular in pattern • Range can be 250 Km or more, station to station • Repeater transmit power is typically 20W to 100W • 28, 50, 220, 146, 440, 1200 Mhz or cross-band • Can be open or closed

Repeaters and Linking This is VE1PAR in the Parrsboro area

Repeaters and Linking \ Repeaters /  Why do we need them? • Mobile radio range is 20 Km to 40 Km • HT range is 2 Km to 5 Km • Repeaters extend the usable range of our mobiles, HT’s • They can be a common gathering place for hams that are spread out, geographically • They can provide important club announcements • They can provide time, date, weather info • They can provide reliable emergency communications

Repeaters and Linking \ Repeaters /  How do they work? • A signal, on Freq A, is received in the repeater antenna • The signal goes down the feed line to the receive port of the duplexer • From the receive port of the duplexer, the signal feeds the receiver radio tuned to Freq A • Freq A is demodulated and the audio is fed to a repeater controller on Port 1 interface card • The audio is routed back out Port 1 to a transmit radio where it is modulated and transmitted on Freq B. • The transmitted RF is sent to the transmit port of the duplexer where it is combined with the receive signal and fed on to the repeater antenna • Both receiving Freq A and transmitting Freq B, usually use the same antenna

Repeaters and Linking Controller Receiver RX COS RX Audio Port 1 Transmitter TX PTT TX Audio

Repeaters and Linking \ Repeaters /  How are they controlled? • A repeater controller device is used • Consists of micro-processor board and interface cards • DTMF tones allow users to control certain functions • RS-232 port allows for programming • Inserts ID’s, hangtimes, decode/encode CTCSS tones, announcements on top of repeated audio • They route the control signals required to key and unkey the transmitter • They time and time limit the received and re- transmitted signals. • They interconnect audio and control signals between I/F cards for the purposes of linking • They can read external sensors like temp and door alarms • They can interface with the phone system

Repeaters and Linking \ Repeaters /  How are they powered? - AC (Hydro/Utility) - AC (Utility w/ backup generator and/or UPS) - Solar powered with 12V battery banks - Wind turbine powered with 12V battery banks  What kinds are there? - Commercially built (Motorola, GE, Yaesu) - Mixture of components (Motorola, GE, Link) - Homebrew (power supply and controller )

Repeaters and Linking \ Repeaters /  Where are they located? • Spread out geographically • Often located on high ground • Often located at commercial sites with other radio systems • Can be found on Repeater lists, MAVCOM codes, etc • ARRL Repeater Handbook • URL: ve1cra.net (under repeater linking) • Google maps • Ask local hams

Maritime VHF Repeaters

Maritime UHF Repeaters

Repeaters and Linking \ Repeaters /  What do I need to know to use them? • What is the rough coverage area of the repeater • What is the frequency I should listen on • What is the offset frequency between RX and TX • What are Sub-audible tones • CTCSS (Continuous Tone-Coded Squelch System) • Superimposes a sub-audible freq on the signal • DCS (Digital Coded Squelch) • Superimposes a continuous stream of FSK digital data, at about 131 baud, on the TX signal • 1750 Hz tone burst (European, but being phased out) • Identifiers (CW, Artificial Voice or DVR) • Different courtesy tones used depending on status • DTMF user codes (Dual Tone Multi Frequency) • DTMF muting and falsing

Repeaters and Linking \ Repeaters /  Digital Voice Modes • DMR (Digital Mobile Radio Standard) – Mototrbo (Motorola) (Springhill) • D-Star (Icom) (Church Lake & Antigonish) • Wires/Fusion (Yaesu) (Southampton, Truro, Antigonish and Yarmouth) • Proprietary in nature • Many systems can autosense and operate in both FM analog and digital modes • Encodes and decodes audio as a digital bit stream • http://www.maritimeamateur.ca/digitalradio.htm

Repeaters and Linking \ Linking Repeaters /  Why do we link repeaters? • To increase the geographical range of repeaters • To be able to communicate to others in other provinces and countries • To be able to pass emergency or relevant communications between regions • To link together hams with common interests

Repeaters and Linking \ Linking Repeaters /  How do we link repeaters? • Terrestrial RF (MAVCOM) • Microwave RF (NB IRG System) • Telephone company leased circuits (TMRS) • Internet (IRLP or Echolink)

Repeaters and Linking \ Linking Repeaters /  How are links controlled? • Repeater controllers control the link radios • Linking uses DTMF on and off codes • 3 or 4 digit codes with an asterisk or pound • Some systems use just numbers • Off codes can sometimes be one unique code (73) or a regular link code • Repeater controllers are programmed to respond to DTMF commands that connect or disconnect that repeater to the link system

Repeaters and Linking \ Linking Repeaters /  What do I need to know to use the linking system? • Where are you right now? • Where do I want to link to? • What are the DTMF codes that are needed to link? • Entering DTMF codes, listening for the right audio responses • Timeout timers on links to be aware of • Network propagation delays • OCTD (One Code To Destination) • DTMF regeneration over links

Repeaters and Linking \ Linking Repeaters /  MAVCOM • Maritime Amateur Voice Communications System • Terrestrial Repeater RF linking over UHF frequencies • Consists of UHF hubs and UHF trunked sites • Link sites are rarely over 60 miles apart • 60% of MAVCOM is half duplex, 40% is full duplex • Uses 4 digit DTMF on and off codes • Link codes are executed when you unkey (Enter) • Audio, voice or CW link status messages are sent to indicate link status • Different courtesy tones can be used when linked • Link inactivity timer is generally 5 minutes • Link activity timer is generally 3 minutes • More than one repeater can be linked at a time • New links always being added (Work in progress) • Link codes follow the Coordinated Dialing Plan (106* on, 107* off)

Repeaters and Linking Controller Port 1 VE1HNS Port 2 Basic Link Between 2 Repeaters Controller Port 1 VE1PSR Port 2

Repeaters and Linking TRUNK LINK SITE MAVCOM UHF BACKBONE VE1HNS VE1MHR Port 2 Port 3 Port 1 Controller VE1PSR

Repeaters and Linking HUB LINK SITE MAVCOM UHF BACKBONE VE1VO VE1KEJ VE1BO Controller Port 1 VE1LCA HUB Port 2 VE1LCA RPTR

Repeaters and Linking \ Linking Repeaters /  IRLP (www.irlp.net) • Uses the Internet for linking repeater systems • Creates a secure, full duplex audio stream between repeater systems using VOiP and PGP keys • The connection point between repeater and the Internet is called a “Node” • Many nodes can be joined together on the internet using a “Reflector” (party line) • There are 2900 nodes and 31 reflectors • Uses a 4 digit on code and a common off code (73) • Node software runs on the Linux operating system • Requires any old computer and the IRLP interface board (installs inside computer) • Node 2050 (VE1NSG/VE1HNS) configuration • Node locations and status can be found online at: http://status.irlp.net • You can add custom codes and features

Repeaters and Linking Halifax, Canada – VE1HNS Controller Port 1 Port 2 Basel, Switzerland - HB9TVW Internet Controller Port 1 Port 2

Repeaters and Linking \ Linking Repeaters /  Echolink • Uses the Internet for linking repeaters and PCs • Security is through a validation process and then username/password • Windows based, but packages available on Linux and MAC • Hard to get an exact number of nodes • Uses a 4, 5 or 6 digit on code and a common off code • Interface uses WB2REM, VA3TO or Rigblaster • EchoIRLP nodes (not able to cross-connect)