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PSK31 – A Popular Digital Mode

Presentation to the

Ole Virginia HamsAmateur Radio Class

by

Karl W4KRLMarch 18, 2006

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What is PSK31?

It is a digital mode using a computer keyboard It is “real time” – other stations see your typing

immediately Enables live contacts between two or more

hams It works great with low power, simple

antennas, and bad conditions It is cheap and easy to connect your rig to a

computer - great software is cheap or free It is a fun way to make contacts around the

world at practically any time of the day

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PSK31 Details

“PSK” Phase Shift Keying modulates the phase of a carrier. ''31'' is the baud rate of the PSK31 signal.

Developed by Peter Martinez G3PLX in the 90’s Initially required expensive, complex hardware. Took off in the spring of 1999 with soundcard

software. Another boost with panoramic tuning. Uses ‘varicode’ to speed up transmission: Frequently

used characters are shorter than others. 50 words per minute is normal typing speed.

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Typical PSK31 Station

14.070

Simple Antenna

HF Transceiver

SoundcardInterface

PersonalComputer

PSK31 Software

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Commercial Hardware

RigBlaster – www.westmountainradio.com RASCAL – www.buxcomm.com MFJ1273/6/9 – www.mfjenterprises.com DigiMaster (USB & rig control) – http://g4zlp.co.uk Donner’s - home.att.net/~n8st/ EZ-PSK – www.hamstop.com RigExpert – www.mixw.net/hardcon.htm PSKMeter - www.ssiserver.com/info/pskmeter PSK-series Transceivers -

www.smallwonderlabs.com

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Homebrew Interface

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PSK31 Software

FreewareDigiPan – www.digipan.netHamScope - www.qsl.net/hamscopeHam Radio Deluxe – hrd.ham-radio.ch

CommercialMixW – www.mixw.netTrueTTY – www.dxsoft.comRCKRtty – www.rckrtty.de

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Where to find PKS31:

HF (High Frequency) PSK frequencies: 160 meters - 1.838 80 meters - 3.580 40 meters - 7.035 30 meters - 10.140 20 meters - 14.070 The place to start! 17 meters - 18.100 15 meters - 21.080 10 meters - 28.120 6 meters - 50.290 2 meters - 144.144

Operation is typically Upper Side Band (USB) mode. Frequencies range from the lower frequency, upward by three (3) kHz.  In theory, a hundred PSK31 signals fit into the same spectrum as one

SSB signal might occupy.

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Other Digital Modes

Morse Code (CW) – When All Else Fails The first digital mode Very simple equipment Can be read by ear

Radio Teletype (RTTY) Hardcore hardware – now much easier Difficult to tune, no lower case letters

Packet – Not dead yet Store and forward – no live contacts APRS – Automatic Position Reporting System

Soundcard Digital Signal Processing (DSP) Revolution A simple path to nearly all digital modes If you’ve got it – use it

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More Digital Modes

HellschreiberAMTOR, Throb, Clover…Slow Scan Television (SSTV)PACTOR and WinLinkDigital Radio Mondiale“HF Digital Handbook” ARRLARRL HF Digital Communications

Course (EC-005)

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PSK31 in Action

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Thank You!

Good luck with your course.See you on the air!