Advanced Digital Modes:Winlink 2000 & Automatic

Link Establishment

Ken Heitner AFA3PB / AFD3AL

NE Division Conference

September 2013

Why Digital Messaging?

• Allows Emergency Traffic to be Handled Quickly and Automatically

• Works with Existing E-mail Systems when They are Available

• Uses Available Internet Resources

• Messaging Mode is Familiar to Most Users

• Can Effectively Utilize Available HF Channels

Winlink 2000 – WinmorHow Does It Work?

• Goal is Low Cost with Robust Performance

• Uses Standard Personal Computer components:– Soundcards, and– USB or Serial (COM) Ports

• All Critical Features are Built into a Virtual Terminal Mode Controller (as software)

• Software Can Also Control the Frequency Setting of the HF Radio Being Used

Winlink 2000 – WinmorVirtual Terminal Node

Controller Handles:• Digital Modulation & Demodulation

• Automatic Retry Requests (ARQ)

• Digital Signal Processing (DSP)

• Forward Error Correction (FEC), and

• Radio Tuning & Soundcard Time Base Errors

• PC Sets Radio Frequency for Best Link to Target Station

Winlink 2000 – WinmorAnd the Bottom Line Is:

• Most Critical Functions of Digital Message Transfer are Handled in Software

• Operator Sets:– Radio mode (and maybe frequency)– Transmit power levels (for radio & amp), and– Choice of initial operating bandwidth

• Most Soundcards Seem to Work Acceptably

• Local and System Software Automatically Route Message to the Addressee

WinLink 2000 - Winmor Network is for All MARS

• Software Package is RMS Express:– Available from: http://www.winlink.org/

• There is Yahoo Tech Group MARS_WL2K

• Setup Uses MARS Service Code (See me!)

• Connects Automatically with WL2K Stations via HF or VHF links or Telnet

• Most Popular Low Cost HF Mode is Winmor Based on Soundcard Interface

Automatic Link Establishment• ALE is Based on a Network of HF Radios Using

the Same Channels & Parameters• AF & Navy MC MARS has 10 Channels 2 – 28

MHz for its ALE Network• Army MARS has Separate ALE Network• Each ALE Station Scans All Channels for

Soundings to Build Link Quality Analysis (LQA)• Each Station Sends One Sounding per Hour on

Each Channel to Establish Link Quality• LQA is Used to Choose Best Channel for Next

Link Automatically

Automatic Link Establishment 2• When a Link is Needed for Voice or Data

Communications are Automatically Established on the Best LQA HF Channel

• Equipment Requirements:– Controllable HF Transceiver (CAT Protocol)– Fast (1 GHz+) Pentium Computer (Win XP)– Wide Dynamic Range Soundcard (16-24 Bits)– Soundcard: Stable Timebase & Low Jitter– Wide Band Antenna or Fast Antenna Tuner

ALE MIL-STD 141-110A Data Modem Terminal

• Military Stations Use MIL-STD Data Terminals – Not Amateur Digital Modes

• Operation with Military Stations After LINK is Either Voice or MIL-STD Data

• M110A DMT is a Separate Software Package That Operates in Modes Compatible with Military Data Terminals

• It is Available at: http://www.n2ckh.com/ MARS_ALE_FORUM/MSDMT.html

ALE MIL-STD 141-110A Data Modem Terminal 2

• M110A DMT Operates Either Independently or With ALE in Follow On Mode

• In Receive: M110A DMT provide Autobaud for Data Rate and Interleave

• Autobaud Eliminates Need to Agree on Settings Before Transmission

• In Transmit: Operator Sets Data Rates and Interleave Based on Experience

Automatic Link Establishment 3• Software for ALE from:

– http://groups.yahoo.com/group/MARS-ALE/

• License File for Transmit–Contact AFD3AL

• This is Cutting Edge Technology for MARS– Enables Joint Operations with Government– MARS Stations in SHARES Get Six Additional

Channels (MARS & SHARES Network!)

• Need More Folks to Try This Out !!!

For Additional Information• Contact Ken AFD3AL

– E-mail to: kenheitner@hotmail.com– WL2K Message to: AFA3PB– TPN Message to: AFA3PB@AFE3MC– Phone: 703-538-4747Phone: 703-538-4747

• Join The Digital Revolution in MARS Today !!!

• You Might Just Learn Something New !!