PSK-31 explained

I have an email asking to explain PSK31. I will do my best but let me know if I forget something. Please note that there are limited abilities to have fun in common PSK31 frequency locations if you have a Technician license. What to do? Upgrade your license to General or Extra, of course 🙂

You can still find it on Tech privilege bands but simply less common.

What is PSK31?

PSK31 is a highly-efficient data mode that lets you work long distances, even when you can barely hear the signal. The “PSK” stands for Phase Shift Keying, the modulation method that is used to generate the signal; “31” is the bit rate.  Unlike RTTY (radio teletype) the characters are formed by changing the phase of the sound wave, not by using different tones.

What are standard PSK31 FREQUENCIES?

The plan for PSK31 activity has always been (since PSK31 started) to concentrate activity starting from the bottom edge of the IARU RTTY bandplan, expanding upwards as activity increased. The exception is in the 10 mts band in order to give non full privileges ham to meet. It was defined as 150 Hz above it. Keep in mind that all you need is about 100 Hz as channel separation.

These recommended frequencies are in accordance with the IARU bandplan for region 1. There may be differences for regions 2 and 3

7035.15 for region 1 and region 3, and 7080.15 for region 2 *
21080.150 (although most activity can be found 10 kHz lower)

(Thank you to to ARRL and ac6v  for partial info)

So now that you know where to find the signal… what do you decode or encode with:

  • MultiPSK
  • DigiPan
    DigiPan provides a panoramic display of the frequency spectrum in the form of an active dial scale extending the full width of the computer screen. DigiPan is the result of a joint effort between myself and Nick Fedoseev, UT2UZ, the author of MIXW32, and is intended to make PSK31 operation easier and more enjoyable for everyone.
  • PSK31 Deluxe
    PSK31 Deluxe is a PSK31 and PSK63 program for novices and power users. It has been replaced by Digital Master 780 and is now a legacy product. The last version of PSK31 Deluxe was shipped with the HRD 4.0 SP4 kit and is no longer available and supported.
  • Fldigi – Fldigi Freeware Digital multi mode program for Linux, Free-BSD, MacOS X and MS Windows . Support CW and several digital modes like PSK31, MFSK, RTTY, Olivia, WeFax, Hell and others and is a fully multi platform application
  • Ham RadioDeluxe – Ham Radio Deluxe. This is a windows based application containing many popular tools all in a single application. This is however not free.
  • Multimode download – This is an OSx based digital mode application. This is also not free but very popular.
  • Cocoa Modem 2.0  – Digital mode software is for Macs that supports RTTY, PSK, MFSK, Hellschreiber, CW, and ASCII transmission along with SITOR-B, HF Fax and Synchronous AM reception. Developed by W7AY.
  • Multimode  – This Mac software called MultiMode allows you to decode and transmit morse code, RTTY, FAX, SSTV, SITOR-B, NAVTEX, PACKET, ACARS, PSK31, ALE, and more without any extra hardware.Tips:

Ask for an RSQ report. (readability, strength, quality)

Get a good contrast setting for your waterfall. Trust me, you will thank me for this. You have to see it to find it. (This will do nothing for reception but tons for visibility)

When transmitting, keep your ALC reading low to make sure your signal is clean.

Attenuate the RF signal and raise the volume and you may see signal readability improve (AGC, Automatic Gain Control, does nothing for a weak signal; it only levels the louder ones.)

Have fun,

Let me know what questions you want me to address. My email is

About K0FEY

I am a member of the Eden Prairie Radio club. This is a Minnesota Ham Radio Enthusiast club and we promote experimentation and learning through the Amateur Radio hobby. Come check into a net on Sunday with us or better yet meet us in person on the 3rd Thursday of the month.
This entry was posted in Digital Modes, Experiments, Ham Radio, Net Topics. Bookmark the permalink.

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