George Zafiropoulos

KJ6VU

George Zafiropoulos

KJ6VU

Personal Background

• KJ6VU

• Licensed in 1972

• Building repeaters since the ‘70s

• Cactus Intertie Nor Cal – Board of Directors

• Bay-Net – Board of Directors

• Builder / trustee of D-Star repeater WW6BAY

Content taken from various

presentations from…

John Hays K7VE

Debbie Fligor, N9DN

Dan Smith, KK7DS

… thanks !

Agenda

• Introduction to D-Star technology

– What is it?

– How does it work?

– What can you do with it?

• Building a D-Star & analog repeater system

• Summary

– Digital vs analog FM – pros and cons

– Using D-Star for emergency communications

What is D-Star ?

• Digital – Smart Technology for Amateur Radio

• ICOM’s implementation of JARL open standard for

UHF/VHF digital voice and data communications

• Equipment on 2 Meters, 440 MHz and 1.2 GHz

• Gaussian Minimum Shift Keying (GMSK) with forward

error correction

Why Should You Care ?

• Digital technologies applied to ham radio

• Spectrum efficiency

• Voice & data provides new options

• Audio quality does not degrade over multiple hops

• Eliminates noise on marginal signals

• World wide digital backbone

• Leverage the internet for backhaul

• It’s fun !

Fun Facts…

• > 16,000 registered D-Star users world wide

• > 680 internet gateways

• ~2,200 active users per day

Conventional wisdom

Proprietary Icom System

Crummy audio

Expensive radios

Very expensive repeaters

6 KHz bandwidth

D-Star First Impressions

Conventional wisdom

Proprietary Icom System

Crummy audio

Expensive radios

Very expensive repeaters

6 KHz bandwidth

My impression now

Open standard (mostly)

Pretty good audio

50% premium

New low cost alternatives

Not quite

Lots of new cool technology

New use models

Great user community

D-Star First Impressions

Conventional wisdom

Proprietary Icom System

Crummy audio

Expensive radios

Very expensive repeaters

6 KHz bandwidth

My impression now

Open standard (mostly)

Pretty good audio

30% premium

New low cost alternatives

Not quite

Lots of new cool technology

Enables new use models

Great user community

D-Star First Impressions

A Brief History of D-Star

JARL defines

D-Star spec

• Icom rolls out first D-Star products

• Early adopters install systems

• Call sign routing

• US usage starts to ramp up

• Popular with emcomm groups

• G1 and D-Plus gateways

• Many new technologies

DV dongle, GMSK Modem, DVAR, Reflectors

2001 2004 2006 2008 2011

• >16,000 users

• >600 repeaters

• DV Access Points

• Non-Icom repeaters

D-Star Infrastructure

Growth of Non-Icom Equipment & Software

2001 2004 2006 2008 2011

DV Dongle DVAP

Radios

D-RATS

DVAR

Hot

Spot

StarGate

Repeater

Repeater Bands

K6ACS Santa Rosa 2m UHF

W6CO Mt. Veeder UHF

KS6HRP Folsom 2m

KD6SAC Citrus Heights 1.2

K6HDD Mt. Bullion 2m UHF 1.2

W6DHS Volcano 2m UHF 1.2

K6PIT Pittsburg 2m

K6MDD Mt. Diablo 2m UHF 1.2

W6YYY Oakland UHF

W6UUU Pleasanton UHF

K6LRG Mt. Alison UHF 1.2

WW6BAY Palo Alto UHF

KI6JUL San Jose 1.2

Available at www.bay-net.org

OUTPUT INPUT CALL LOCATION SPONSOR

144.9600 144.5600 W6DHS Volcano N6RDE

145.0400 144.6400 K6ACS Santa Rosa KD6RC

145.1300 144.5300 W6HHD Mariposa W6HHD

145.4500 144.8500 K6VIS Visalia TCARC

146.5800 147.5850 K6MDD Concord K6MDD

146.8950 146.2950 K6CHO Chico AREA 147.2400 147.8400 K6PIT Pittsburg K6PIT

147.6750 147.0750 KS6HRP Folsom SHARP

440.0375 445.0375 W6YYY Oakland N6LDJ

440.0500 445.0500 K6VIS Visalia TCARC

440.6000 445.6000 W6DHS Volcano N6RDE

442.1125 447.1125 K6ACS Santa Rosa K6ACS

443.8500 448.8500 WD6SJV Dunlap DCTS

444.0750 449.0750 WW6BAY Palo Alto BAY NET

444.1375 449.1375 K6MDD Concord K6MDD

444.6875 449.6875 K6LRG Fremont K6LRG

444.8000 449.8000 W6HHD Mariposa W6HHD

>24 DV Repeaters and >7 DD Nodes

In Northern California

OUTPUT INPUT CALL LOCATION SPONSOR 1284.1000 1272.1000 W6HHD Mariposa W6HHD 1284.2000 1272.2000 K6MDD Concord K6MDD 1284.5000 1272.5000 KD6SAC Folsom K6HLE 1285.3000 1273.3000 WD6SJV Dunlap DCTS 1286.3250 1274.3250 K6VIS Visalia TCARC 1286.5250 1274.5250 K6CHO Chico AREA 1286.5250 1274.5250 KI6JUL San Jose AREA 1286.6250 1274.6250 K6LRG Fremont K6LRG

1249.0750 1249.0750 K6MDD Concord K6MDD1249.2250 1249.2250 W6HHD Mariposa W6HHD1250.0000 1250.0000 WD6SJV Dunlap DCTS1255.0000 1255.0000 K6VIS Visalia TCARC1299.3500 1299.3500 K6CHO Chico AREA1299.3500 1249.3500 KI6JUL San Jose AREA1299.5000 1299.5000 KD6SAC Folsom K6HLE

Digital Voice

Digital Voice

Digital Voice

Digital Data

Repeater Status

D-Plus Dashboard – Reflector Status

User Registrationhttps://dstargateway.dcara.net/Dstar.do

• You can listen but not

access a repeater

until you register

• Centralized

registration system

• Free

• Allows you to use any

D-Star repeater

Using D-Star Simplex

WW6BAY G

TALKING TO K1XYZ

K1XYZ

VK8RAD G

Boston, MA

San Jose

W6ABC = MyCall

UrCall =

RPT2 =

CQCQCQ

WW6BAY BRPT1 =

K6DEF

UR = CQCQCQ

RPT1=

RPT2=

MY = W6ABC

Using D-Star for On a Local Repeater

WW6BAY G

TALKING TO K1XYZ

K1XYZ

VK8RAD G

Boston, MA

San Jose

W6ABC = MyCall

UrCall =

RPT2 =

CQCQCQ

WW6BAY BRPT1 =

K6DEF

UR = CQCQCQ

RPT1= WW6BAY B

RPT2=

MY = W6ABC

Using D-Star

Repeater to Repeater Linking

WW6BAY B

WW6BAY G

TALKING TO K1XYZ

K1XYZ

VK8RAD G

Boston, MA

San Jose

W6ABC = MyCall

UrCall =

RPT1 =

RPT2 =

CQCQCQ

UR = CQCQCQ

RPT1= WW6BAY B

RPT2= WW6BAY G

MY = W6ABC

Using D-Star Reflectors

WW6BAY B

WW6BAY G

TALKING TO K1XYZ

K1XYZ

Boston, MA

San Jose

W6ABC = MyCall

UrCall =

RPT1 =

RPT2 =

CQCQCQ

Reflector

Gateway

Gateway

UR = REF014CL

RPT1= WW6BAY B

RPT2= WW6BAY G

MY = W6ABC

Cool Stuff…

D-VAP – Digital Voice Access Point

• 1 mw 2m simplex data radio

• USB connection to the PC

• Provides portable RF access

to the D-Star network

• All you need is an internet

connection

• Take the network with you

Cool Stuff…

DV Dongle

• Turns your computer into

a D-Star “radio”

• Built in DVSI CODEC

• Simple PC program

controls the dongle

• Windows, MAC, Linux

The Cost of D-Star

$530$290

$479$329

Conventional Conventional & D-Star

the cost of

1-2 CW Filters

D-Star is…

What’s Inside D-Star?

• Data rates

• CODEC

• Data format

• Bandwidth

• Modulation

Data Rates & Bandwidth For DV Mode

(What you use on 2m & UHF)

2400 bps AMBE encoded voice

1200 bps Forward Error Correction (FEC) for voice

1200 bps data (text messages, GPS, etc…)

4800 b

ps

“Slow speed data mode”

DVSI = Digital Voice Systems Inc

“World leader in low-bit-rate speech compression technology”

Designer of the AMBE CODEC algorithm and chips

Used on satellite phones and land mobile applications

Anyone can buy the chips for about $20

DVSI AMBE 2020 CODEC chip

DVSI AMBE 2020 CODEC chip

Digital Voice Data Format – Header Section

CQCQCQ WW6BAY B WW6BAY G W6ABC BOB

Digital Voice Data Format – Data Section

D-Star Bandwidth

Better Than Traditional Narrow Band FM

40 db down @ 6 Khz away 20 db down @ 6 Khz away

D-Star uses GMSK modulation

Gaussian Minimum Shift Keying

• D-RATS

• DStarlet

• d*Chat

• Dstarusers.org

• D-PRS interface/javAPRSSrvr

• uSmartDigi D-Gate D-STAR Gateway D-STAR/APRS

Interface

• D-STAR query

• Opendstar.org Applications

Other D-Star Applications

D-RATS

Slow speed digital mode application

• All-in-one tool for D-STAR data

• Real uses for the data channel

• Oriented at EmComm applications

• No dependence on infrastructure

• Works on simplex

• Works on a gateway network

Features• Email

• ICS & Radiogram forms

• Messaging

• Chat

• File transfer

• Position reporting

Runs on…• Windows

• MAC OS

• Linux

D-RATS

Chat

Email

Traffic Forms

Position

reporting

Agenda

• Introduction to D-Star technology

– What is it?

– How does it work?

– What can you do with it?

• Building a D-Star & analog repeater system

• Summary

– Digital vs analog FM – pros and cons

– Using D-Star for emergency communications

Intro to Bay-Net

• History

– 1999 ARC State Lead Unit & Cactus sign Statement of Understanding

– 2005 Bay-Net created by NCCRA - First NCCRA “open repeater” system

– 2006 Started working with ARCBA and Orinda ARES

• Goal

– Open repeater system covering the bay area

– Supporting public service organizations including

American Red Cross Bay Area chapters

Orinda ARES

• Financial and technical support by

– System owners

– Northern Cal Cactus Radio Association

– Sierra Radio Systems Bay-Net

South Bay

East Bay

Bay-Net System

San Bruno Fire

6:20 Burlingame Red Cross comm team

alerted to check in to Bay-Net

6:25 Emergency net activation

Cell phone system was unreliable

– Network overload

- Equipment failure at fire site

Bay-Net was the main communications link

between…

• Burlingame Red Cross

• San Bruno EOC

• ICP

• Evacuation Center

Nets running for more than one week

Bay-Net

145.390

Repeater

443.225

Repeater

927.8625

Repeater

IRLP / EchoLink

ComputerLink

Radio

145.390

Repeater

Control System

443.975

Repeater

Link

Radio

Control System

Link

Radio

Black Mountain East Bay Hills

Internet

444.075

Repeater

Computer

Modem

Internet

Black Mountain

2800’ Above Silicon Valley

444.350 Duplexer

444.075 Duplexer

GaAs FET Preamp

& Cavities

444.350 Repeater

444.075 Repeater

Cactus 420 Link Radio

Control System

Site Controller

D-Star Computer

Site Controller Computer

WW6BAY D-STAR Block Diagram

Celwave 526 Duplexer

Angle Linear GaAs FET

preamp and filter

Maxtrac Rx Maxtrac Tx

Satoshi modem board

Intel ATOM mobo

Centos 5.4

G4ULF NI-Star SW

USB

InternetEthernet

1U Mini-ITX ATOM Motherboard

Centos 5.4 Linux OSDavid Lake’s “NI-Star” Software

1U Mini-ITX ATOM Motherboard

30 GB SSD Intel Atom Motherboard DC / DC converter Power control relay

WW6BAY Hubs on Reflector 14C

www.bay-net.org

Agenda

• Introduction to D-Star technology

– What is it?

– How does it work?

– What can you do with it?

• Building a D-Star & analog repeater system

• Summary

– Digital vs analog FM – pros and cons

– Using D-Star for emergency communications

Digital vs Analog

Analog

Digital

Solid copy

Solid copy

Increasingly noisy

“R2D2”

No

Signal

No

Signal

Not intelligible

Many claim one has better range than the other

Too close to tell

However, D-STAR hangs in longer without noise

Both Have Downsides…

Analog

– Gets noisy

– Squelch tails

D-Star

– Disruption in the header (first 600 bits)

will cause the whole transmission to fail

– More complicated setup and operation

D-Star for Emergency Communications

For voice comms - conventional FM is generally better

– Universally interoperable

– Easy to use

– Cheap

How can D-Star be used?

– D-Star can be ideal if you have internet access

using a D-VAP

– Excellent secondary support system

– Use data channel for position and messaging

– Callsign routing can be very handy

– Wide area / out of area comms

Summary

• D-Star is an exciting mode

• Lots of potential

• Excellent secondary mode

for EmComm

• Give it a try

• Jump on in !