1 PSK31 – A Popular Digital Mode Presentation to the Ole Virginia Hams Amateur Radio Class by Karl W4KRL March 18, 2006

2 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

3 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 90s 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.

4 Typical PSK31 Station Simple Antenna HF Transceiver Soundcard Interface Personal Computer PSK31 Software

5 Commercial Hardware RigBlaster – RASCAL – MFJ1273/6/9 – DigiMaster (USB & rig control) – Donners - home.att.net/~n8st/home.att.net/~n8st/ EZ-PSK – RigExpert – PSKMeter - PSK-series Transceivers -

6 Homebrew Interface

7 PSK31 Software Freeware DigiPan – HamScope - Ham Radio Deluxe – hrd.ham-radio.chhrd.ham-radio.ch Commercial MixW – TrueTTY – RCKRtty –

8 Where to find PKS31: HF (High Frequency) PSK frequencies: 160 meters meters meters meters meters The place to start! 17 meters meters meters meters meters 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.

9 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 youve got it – use it

10 More Digital Modes Hellschreiber AMTOR, Throb, Clover… AMTOR Slow Scan Television (SSTV) PACTOR and WinLink Digital Radio Mondiale HF Digital Handbook ARRL ARRL HF Digital Communications Course (EC-005) ARRL HF Digital Communications

11 PSK31 in Action

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