1. Introduction to Digital Radio & PSK31
Josh KD8SLQ
Chris AB3YS

2. Agenda What is Digital Radio? Advantages of Digital Radio
Hardware Requirements
Software Requirements
Digital Calling Frequencies
Operating Procedures
Control Interface Features
Comparing Operating Modes
Other Features
Notable Contacts
Conclusion

3. What is digital radio? Radio communication via computer.
PSK31 is one of the most popular methods
PSK31 stands for Phase Shift Keying and will transmit a signal 31 Hz wide.

4. Advantages of digital radio
Fast data exchange
Messages can be sent in a matter of seconds
High degree of error correction
Small bandwidth
Exchanges can be automated using macros for fast response.
Lower power requirements compared to voice
Resistant to interference
Can be done with desktop computers and base station radios or with laptops and mobile radios for portable operation.
Does not require listening. Good for the hard of hearing or places with noise constraints.

5. Hardware Requirements
TNC to Radio Connection
Dedicated DATA port
Custom interface
RX audio from speaker or headphones
TX audio from computer soundcard
PTT control
Recommend isolation transformers and audio limiters to protect equipment.
Radio Controller (Optional)
RT Systems
Direct Connection via USB or Serial Port
Computer
Must have sound card or ports for external sound card
Radio
Interface
Radio Sound Interface
SignaLink
Terminal Node Controller (TNC)
West Mountain Radio
MFJ TNC’s

6. Hardware Setup Signalink USB
Popular radio interface.
~$100 new with interface cable of your choice. Specify when ordering.
Powered by computer’s USB, no external power needed.
Wide variety of radio interface cables available (~$20), or make your own.
Easy setup in Windows computers.

7. Hardware Setup System setup With Signalink USB
Radio Control Cable (Optional)
USB Cable
Transmit Audio
Receive Audio
PTT Control
Feedline to antenna
Commonly one cable.

8. Software Requirements
Windows
DigiPan
FLDigi
Free & Open Source
Ham Radio Deluxe with Digital Master 780
Version 5.24 free to download.
Later versions must be purchased.
Packet Engine Pro
Linux
FLDigi
Mac
cocoaModel
Multimode

9. Operating Procedures Select base frequency via VFO.
PSK31 requires USB, even below 10 MHz.
Multiple stations are clustered around one frequency, with varying modulation to separate signals.
Once tuned, do not change VFO. Suggest locking VFO, if possible, to prevent bumping.
Setup your call sign in software. Used as part of communication packet.
Set output power to max 50% of radio or amp. Digital radio is 100% usage and may damage the radio if used at higher power.
Select modulation on the waterfall display.
Will decode any messages on that modulation.
Type in message or select macro. Hit send/Auto.
Call sign is included at the start of each message sent, so regular ID’ing is not required, only when you end a conversation.

10. Popular Digital Calling Frequencies
160 meters: MHz
80 meters: MHz
40 meters: MHz
30 meters: MHz
20 meters: MHz
Most popular PSK31 location
17 meters: MHz
15 meters: MHz
12 meters: MHz
10 meters: MHz
6 meters: MHz
2 meters: or MHz
Normally horizontally polarized
160 to 12 meters require General or Extra
10, 6, & 2 meters allow Technician license

11. Operating procedures Calling CQ audio in various modes
PSK31
PSK63
OLIVIA
RTTY

12. Operating Interface Features Overview
Logging Info
Macro Menu
Text Interface
Waterfall

13. Operating Interface Features Text Interface
Received data window
Send, leaves PTT closed until canceled.
Auto, opens PTT when finished with text in window
Macro Quick Keys
Transmission text window

14. Operating Interface Features Waterfall

15. Operator Interface Features Transmitting
Progress of transmission. Text being sent struck-through as transmitted.
Audio being transmitted shown on waterfall.

16. Operator Interface Features Other Functions

17. Operator Interface Features Supersweeper
Vertical waterfall
Decodes multiple signals simultaneously.
Allows you to pick which signal you want to interact with.

18. Operator Interface Features Software
Most software can decode multiple types of digital signals
PSK63
RTTY
Contestia CW
Some software can decode SSTV (Slow scan TV)

19. Comparing operating modes
PSK31
Very popular
Narrow bandwidth
Effective
Good for contests, rag chewing, etc.
PSK63
Faster than PSK31
Larger bandwidth
Not as popular

20. Comparing operating modes, Con’t.
JT-65
Created by Nobel Prize winner Joe Taylor, K1JT.
Very accurate because of error correction built in.
Can sometimes work even if not audible to the ear.
Popular
Olivia
Good during bad band conditions.
Wider Bandwidth.
Not very popular.

21. Comparing operating modes, Con’t.
RTTY (Radio TeleTYpe)
Old mode, created in 1922.
Popular, especially in Europe.
Popular with Contests.
Slower than PSK31
Very regimented contacts. Watch a lot of QSOs to learn expected procedures. CW
People tend to have mixed feeling about computer generated CW.
Computer decoding not always accurate.
Other modes
Hellschreiber
Domino

22. Operator Interface Features Radio Control via HRD

23. Other Features HRD Remote Radio Control
HRD enables radio computer control of your radio via CAT interface.
Depending on the radio, this can allow for full radio control by computer.
Remote operation of a radio via two computers connected over a network.

24. Other Features PSK Reporter
Stations heard on DM780 & FLDigi can be sent to share what stations are heard with an online tracking system.
See real time digital activity
Track your receiving and transmission capability.
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25. Other Features PSK Reporter
See all stations that you hear
See all stations that can hear you
See details on individual contacts.

26. Notable contacts by Chris AB3YS

27. Conclusion
Thank you for attending.
Questions?
Live Demo