Title: The Internet Radio Linking Project
1The Internet Radio Linking Project
I.R.L.P
- Presented by K1IMD
- For the Peconic Amateur Radio Club
- 1 June 2001 Meeting
Portions of this presentation are reproduced by
written permission of David Cameron VE7LTD
2Topics of Discussion
- Jon K1IMD
- IRLP System Designer
- Introduction
- History of Linked Repeaters
- How it Started
- IRLP Node Equipment
- Hardware
- Pictures of Node 449
- Pictures of Node 448
- Pictures of a typical IRLP Node Installation
- Modes of Operation
- Reflector Mode
- Point to Point Mode
- What does it (Voice over IP) sound like?
- What does a QSO Sound like
- IRLP Node Status
- IRLP Operation
- How To IRLP
- Non-Amateur Uses of IRLP
- The END!!
3Jon Andrews K1IMD
- Jon Andrews was first licensed as an amateur in
1971 where he was issued a novice license WN2CBX.
A year after his novice license expired he
retook the exam and was again issued a novice
license with the call WN2YVL, shortly after that
in 1974 he took the Technician exam and was given
the callsign WA2YVL. In 1995 Jon passed his
Advance class license exam and soon changed his
callsign to K1IMD. - Jon has experimented with many facets of the
hobby, Fixed Station and Mobile operation. VHF,
UHF and Microwave and modes including CW, AX.25
Packet, TCP/IP Packet, FM FM Repeaters, AM,
SSB, AMTOR, RTTY, SSTV, and Fast Scan ATV.
However, of most interest over the years has been
in linking FM voice repeaters. In his basement
he has a shop where he likes to tinker with
projects in his limited spare time. - Jon stays busy with his family and work but does
still find time to experiment, build some
projects and maintain some equipment of others.
Jons latest experiment is the Internet Repeater
Linking Project pioneered and designed by David
Cameron VE7LTD. - Jon is the Chairman of the Board of the Peconic
Amateur Radio Club and an active participant in
the local ARES unit where he serves as an AEC.
4IRLP System Designer
Note! Important Point David is NOT an ole
Buzzard Ham
- Callsign VE7LTD Codes E CANADA
- Name David Cameron
- Addr1 4708 CAULFIELD DRIVE
- Addr2 WEST VANCOUVER, BC V7W1G2,
- Country CANADA
- Lookups 130
- Birthday 06 Aug 1975
- Email ve7ltd_at_irlp.net
- Home Page http//www.irlp.net
- The above courtesy of http//www.qrz.com
5Introduction
- The aim of the Internet Radio Linking Project
(IRLP) is to provide a simple and easy system to
link radio systems together using the Internet as
the communications backbone. - Similar linking options exist, but they use
expensive leased telephone lines or satellite
equipment. It is not the goal of this project to
compete, but to work along with other networks to
improve the technology and improve radio linking
for all involved parties. The people who benefit
most from the IRLP are its users. - The software and hardware requirements are
minimal, and the cost to set up a node is low.
This brings the opportunity for smaller more
remote locations, or small clubs, to experience
national linking without the large capital cost
of a satellite node or leased line.
This and the next 4 slides are taken from the
IRLP website and as spoken by VE7LTD
6History of Internet Linking
- Back in December of 1996, I was flipping through
the many magazines at the UBC club. I came across
the December 1996 issue of the QST Amateur Radio
magazine that had the words "Link your repeater
to the Internet" written on it. I had a quick
read through the issue and found a well written
article by James Millner, WB2REM entitled 'A New
"Band" for Your Radio'. At first glance, I was
hooked. What more could I ask for? It was a
combination of the two hobbies that I love the
most. - My first connection used VocalTec's Iphone. The
original article by WB2REM used Iphone to send
the voice over the internet. I did have some
problems with the software, mainly in the fact
that Iphone is not very stable nor is it
controllable. After running Iphone for close to 6
months on active connections to Vernon BC and St.
John NB, I decided that the stability and control
were key. That is when I started getting into
using LINUX as an operating system and Speak
Freely as a client/server. - Speak Freely is a voice over IP client/server
package that transmits live audio (i.e. speech)
over the internet with surprising clarity and
quality. This program basically allows any two
parties anywhere on the internet to have a voice
conversation with each other in real time. My
objective, and the objective was to use this
program to link to radio equipment so that voice
connections can be made without the operator
being tied to a computer. This will allow hams
from all around the world to talk to one another
without relying on radio conditions.
7History Continued
- Many amateurs have raised a very important
question regarding this kind of system What if
non-ham users start connecting to ham repeaters?
With all the experienced "hackers" out there, I
can not say that this system is totally
bullet-proof. I have designed safeguards into my
software to reject calls from "non-hams". - The main hurdle I had to overcome was the
interface between the computer and the radio.
From my experience with VOX circuits under
Iphone, I decided that I HAD to find an alternate
way to start sending audio and to key the radio
when audio came in (from the internet side).
Since the source code for Iphone was not
available, I had to look for an alternative. I
was told about Speak Freely by a friend of mine,
and I decided to give it a try. - I played around with modifying the source code
for several weeks and finally came up with some
code that works. The software starts the link
radio transmitting once packets have been
received over the internet and unkeys once they
stop coming in. The software starts sending audio
once a signal is received and continues to send
it until the signal is removed. This logic
control is performed using the parallel port of
the computer and all the computer chips are on a
separate interface controller board. I have
designed this board, and I am building them and
selling them at cost to promote the project.
8History - Conclusion
- The whole system is DTMF controllable. The
control codes lie imbedded in a separate program
that reads the DTMF tones from the decoder chip
(located on the interface controller board) and
activates various parts of the software. DTMF
codes are used to enable/disable linking,
open/close links and set identifiers. Every site
will have the ability to connect direct to any
other site(s), either using direct connections or
reflector sites. - So in a period of 8 months, I switched from a
piece of software and hardware that someone else
built, to my own creation which solved all the
previous problems I was experiencing! Ever since
the IRLP started, I have never again looked to
Iphone or Windows for an option in the system. - This history section is taken by permission
from http//www.irlp.net website and is in
VE7LTDs words of his Project History
9How IRLP Started
- The Internet Radio Linking Project was started
back in November of 1997 as an attempt to use the
internet to link radio systems across Canada. The
first full time link that was established ran
from Vancouver, BC to Saint John, NB. The link
had many problems and was shut down in March of
1998 due to the numerous computer crashes and
repeater lockups it was causing, and the lack of
user control over the system. - I set out to design a better way to use the same
technology to perform the same task, while
improving usability, user control, and sound
quality. My first breakthrough was to replace the
existing operating system, Windows, with a more
stable and versatile language. I chose Linux, an
open source form of the operating system UNIX
designed by Linus Torvolds, because of its
superior networking characteristics, its
reliability, and its ease of programming. P.S
Thanks to those on SLASHDOT for clarifying this! - I designed my own interface board to interface
the radio to the computer. This allowed a large
amount of delay to be removed from the system
because two VOX circuits were no longer being
used . I also wrote my own custom control
software, and modified an existing voice-over-IP
software package to accommodate the project. - The final product was a combination of hardware
and software that created a nearly seamless radio
link between two remote sites on the internet.
The product works so well that many people can
not believe that they are talking through a link
at all!
10ILRP Node Equipment
- IBM Clone Computer 80486DX4-100, 80586-75 or
faster - VGA Monitor
- Keyboard no mouse is used
- Functional Printer Port on LPT1
- Red Hat LINUX Ver 6.2 running in text mode
- IRLP files which is on the Custom RH LINUX CD-ROM
- Creative Sound Blaster Sound Card
- IRLP Ver 2.0 Interface Board
- Internet Connection that supports at least
8K/s-64K/s - With 7 ports mapped from a router or directly
connected - Link Radio or Direct Connection to a Repeater
- Installation Instructions downloaded from the
IRLP website
11Hardware
- The Custom Red Hat CD-ROM
- Red Hat Boot Floppy Diskette
- Custom PCB by VE2LTD
- PCB Does COR, PTT DTMF
- DB9 IRLP to Repeater Interface
- LPT1 to IRLP Jumper Cable
12Pictures of Node 449
Rear View of CPU with IRLP board installed
13Pictures of Node 449
CPU side view with IRLP Board installed
14Pictures of Node 449
CPU with Software Hardware installed in a
small case ready to go
15Pictures of Node 448
Node 448 installed in K1IMD Repeater Rack
16Pictures of Node 448
The K1IMD Repeaters System Rack Dont ask where
the Red Wire Goes!!!!
17Typical Node Setup No.1
8-64Kb Internet connection To another IRLP Node
RF Link
CATV/xDSL MODEM
10Mb Ethernet Connection
Repeater or Remote Base
PTT COR Audio
Router
RF Link
10/100Mb Ethernet Connection
Repeater Controller Link Port
Link Xcvr
Link Xcvr
PTT COR Audio
PTT COR Audio
IRLP Computer w/ Custom Red Hat 6.2 O/S
18Typical Node Setup No.2
8-64Kb Internet connection To another IRLP Node
RF Link
CATV/xDSL MODEM
10Mb Ethernet Connection
Repeater or Remote Base
RF Link with CTCSS gating COS
PTT COR Audio
Router
10/100Mb Ethernet Connection
Repeater Controller Link Port
PTT COR Audio
Link Xcvr
IRLP Computer w/ Custom Red Hat 6.2 O/S
19Node 448 K1IMD
8-64Kb Internet connection To another IRLP Node
RF Link
CATV MODEM
Micor UHF Repeater
10Mb Ethernet Connection
PTT COR Audio
ACC RC-850 Repeater Controller On Link Port 3
NetGear RT314 Router
PTT COR DTMF Audio
10/100Mb Ethernet Connection
IRLP Computer P-166MMX w/ Custom Red Hat 6.2 O/S
20Modes of Operation
- There are two modes of IRLP operation
- Reflector Mode Streaming Multiple Audio Streams
- Much like a party line everyone hears everyone
else - Point to Point Mode Only two repeaters are
linked - This mode is much like linking two repeaters
together via a link radio or remote base
21Reflector Mode
RPTR
RPTR
RPTR
RPTR
RPTR
IRLP Reflector
RPTR
RPTR
22Point to Point Mode
RPTR
IRLP Server
RPTR
23What does it sound like?
Voice over IP (VoIP) must sound Weak, Buzzy,
Crummy Digital Sounding Voice NOT!!
- The underlying VoIP software is a program called
Speak Freely it is digital and sounds GREAT! - In fact, unless you knew you where connected to a
data link, you would never know! - Everyone sounds like locals!!
24What a QSO Sound Like?
Reflector Mode
- This is an actual connection and QSO on the IRLP
Reflector 2 Denver, Colorado on 5/10/2001 at
about 1830 EDT - Sounds pretty good huh?
- (This audio was captured via the microphone on my
PC and accessing the system with my HT)
25What a QSO Sound Like?
Direct - Point to Point Mode
- This is an actual connection and QSO to the
VE1NSG Node in Halifax, NS on 5/17/2001 at about
2010 EDT - Sounds GREAT huh?
- (This audio was captured via the microphone on my
PC and accessing the system with my HT)
26IRLP System Node Status
- To see an active update of the IRLP network and
nodes activity go to - http//www.irlp.net/15-status/body.html
- Many nodes have a single page webpage that gives
local information about the node, repeater or
location at - http//www.irlp.net/05-nodes/body.html
27IRLP - Eastern Long Island, New York - Node K1IMD
28IRLP Operation
- IRLP is very much similar to other linked
repeater systems. The only difference is that
the link is done via the Internet utilizing VoIP
(wire) v.s. a telephone pair or a RF link via
radio or microwave. - What this means is that in when you push your
Push To Talk (PTT) button you are actually keying
ALL repeaters in the network PTT as well. - This could be only one Repeater in a Point to
Point Connection or many many repeaters virtually
all over the world in the Reflector Mode - You quite literally have worldwide access to
other IRLP nodes around the world that you can
link to via DTMF commands
29How To IRLP
- Have a basic understanding how the system works.
- Contact your local Node Op for his/her Rules on
use of his/her repeater, link system and the IRLP
system interconnect. - In general, some node ops leave the system
connected on a Reflector. The most active and
common reflector is Reflector 2 in Denver
Colorado. Other node ops leave the system
disabled but available to be connected on DTMF
commands. - Once the local repeater is connected to the IRLP
network, you can commence with a normal QSO as
you would with a local.
30How To IRLP
- However, there are some courtesy's and protocols
that you must follow - As mentioned on previous slides, you are keying
up one to many transmitters around the world.
This takes TIME!! Before you speak Press your
PTT Button and pause for 2-3 seconds to allow all
the systems to key-up. - When a person comes back to you WAIT for 3-4
seconds before responding this allows others to
join in the QSO and more importantly, allows node
control ops to disconnect from the IRLP Network.
Only one node can talk at a time and that
includes controlling!! - When you sign on the custom is to ID and give
your geographic location or node you are coming
in on. - REMEMBER Like other Amateur Radio modes it
is a GLOBAL medium and your actions are a
reflection of you, the node owner, hams in your
area and the citizens of the country you are
from!!
31Non-Amateur Radio Uses of IRLP
- We would also like to add that this project does
not only cover the scope of amateur radio, but
also includes several commercial applications as
well. A couple of commercial uses include - Replacing leased lines used by national carrier
companies. - IRLP designed and implemented a central homed
system for dispatch of multiple vehicles across
the province of British Columbia using internet
links, mountain-top repeaters, and remote base
radios. The IRLP system was interfaced directly
into an existing console, and the dispatchers did
not notice a difference in functionality. - Replacing older technology paging equipment.
- IRLP designed and implemented a multi-cast voice
paging network (4 transmitters) for a remote
school district in British Columbia without the
use of RF based links between sites. This saved
the school district thousands of dollars in RF
gear and reduced the operating cost of their
paging system by 75. - Monitoring of remote areas for security reasons.
- Connecting people from remote offices together.
- The above information is by David Cameron - VE7LTD
32For More Information
- For more information on NODE 448 contact
- k1imd_at_arrl.net
- For General Information about IRLP, on the WWW
see - http//www.irlp.net
- For Node Activity and connection Status, on the
WWW see - http//www.irlp.net/15-status/body.html
- For Node Information Web Pages, on the WWW see
- http//www.irlp.net/05-nodes/body.html
33THE END!
- If youre really serious about expanding your
Repeater Coverage think IRLP! - Thank you for your interest tonight
- 73 de K1IMD