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Digital Communications

PSK31

Bob Wilton – KF5TPQ

Digital Communications – PSK31

Digital Communications Overview

PSK31 – What is it?

Hardware Considerations

Software Considerations

Ham Radio Deluxe – DM780

Configuring

Lets look at a QSO

Other Resources

Questions (Ask questions anytime)

Digital Communications

Computers and digital data

Text data

1’s and 0’s, bits, bytes, characters, variable character sets

Transmission modes – AFSK, PSK (frequency vs phase shifting)

Bandwidth

Signal to noise ratio

So many Operating modes

RTTY, PSK31, JT65, JT9, Winlink2K, Olivia, Opera, Hell, and more

PSK31 and Winlink2K (Georgia ARES)

Digital Bands

PSK31

Why PSK31 ?

Widely used and just a good place to start

BPSK (Binary Phase Shift Keying – 180 degrees)

Low power: 5 – 40 watts (lower the better)

100% duty cycle

ALC and IMD considerations

Bandwidth approximately 31 hz

Throughput – up to about 50 words per minute

Varicode character set

Variable length, e = 11, E = 1110111

Works well in poor noise and poor propagation conditions

PSK63 and PSK125

PSK31 Frequencies

10 Meters – 28,120

12 Meters – 24,920

15 Meters – 21,080

17 Meters – 18,100

20 Meters – 14,070

40 Meters – 7,080

80 Meters – 3,580

Hardware Considerations

HF Transceiver

Computer (or laptop or even a tablet)

Interface

Audio and ptt

Line out

Sound card

Line in

Mic Audio out

Hardware Considerations

Homebrew

Line out

Sound card

Line in

Audio out

100k 1k

Mic

22k

2N2222

1N4148PTT

Serial

RTS

PTT via serial port

(RTS, DSR, or similar

signal line)

Hardware Considerations

Mic

Audio out

Sound

Card

Interface

West Mountain Radio RIGblaster

(about 5 types)

MFJ make a few

MicroHAM

RigExpert

SignaLink USB Interface

Many more, inc many homebrew

designs starting at about $10

Software Considerations

Windows, Mac, Linux, IPAD, Android

Multiple “FREE” software programs available

Ham Radio Deluxe – DM780

Digipan

Fldigi

Hamscope

WinWarbler

And more………….

Ham Radio Deluxe version 5 - Free

Ham Radio Deluxe - HRD

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

Ham Radio Deluxe – DM780

PSK63

PSK125

Ham Radio Deluxe – DM780

Additional Resources - PSKReporter

Additional Resources – HDRlog.net

Additional Resources – QRZ.com

Additional Resources - Google

Digital Communications – JT65

Digital Communications - JT65

CQ N0RQ EM13 (I CQ)

N0RQ W1AW FN31 (he answers with his grid)

W1AW N0RQ -06 (I send signal report)

N0RQ W1AW R-13 (he sends Roger and my signal report)

W1AW N0RQ RRR (I acknowledge receipt of his report)

N0RQ W1AW 73 (he sends a standard or freeform 73)

10W DIPOLE 73 (I send a freeform or standard 73 – contact

is over)

Digital Communications – JT9

Questions

Anytime

bmwilton@live.com

706-896-8990

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