31 Flavors Sprint – Heads Up !

stan robinson

The Ø7Ø Club 31 Flavors Sprint is just 1 week away -

Saturday, April 4 -  1000 UTC   - Saturday     6:00 a.m. EDT

to Sunday, April 5 – 0400 UTC – Saturday  11:59 p.m. EDT


This is an 18 hour event –Saturday 6:00 a.m. EDT to 11:59 p.m. EDT Saturday in US.

This is a chance to try 6 different PSK modes.  Check your software - most will do all PSK Modes.  6 mode variants in play:

·         BPSK 31 [Narrow bandwidth]

·         QPSK 31 [Narrow bandwidth]

·         BPSK 63 [Wide bandwidth]

·         QPSK 63 [Wide bandwidth]

·         BPSK 125 [Very wide bandwidth]

·         QPSK 125 [Very wide bandwidth]

Sprint Rules – Work a 6 hour block of your choice. For Scoring, your 6 hour block will start with the hour you select on the Upload Link page and continue for the next 6 hours


Work each station once per mode. (Same station, same mode, is a dupe!)


Open to all licensed radio amateurs.

Frequencies: - 20 Meters only
- Normal PSK sub-band for narrow mode variants,
- Sub-band 14072.5 - 14080 kHz suggested for wide bandwidth mode variants.

3 Power Categories:

QRP < 5 W
Low < 25 W
Medium < 50 W


- Members: State/Province/Country (SPC) + 070 Member Number   eg: “FL  1611”

- Non-Members: State/Province/Country (SPC) + First Name  eg. “FL  Stan”



All entry logs
 must be received within 1 week after the event ends. A 31 Flavors Uploader link will be available on the PODXS 070 Home Page.


For Rules and detailsClick Here: 31 Flavors Sprint Rules

This is one of our most interesting contests.
If you have never tried these different PSK modes, don't be shy.  Jump in and give it a go! 


Take your time and be patient.  You’ll be an expert in no time!


Last year, 22 logs were submitted. Lee, N5SLY, won Top Dawg honors and First Place in the 50W category with a spectacular 79 QSOs utilizing all 6 modes, and a score triple that of his closest competitor.


Let’s see if we can give Lee some competition this year ! 

Hope to work you in all 6 modes




W9SMR - 070  #1611

PODXS 070 - PR Director

Mike W4BZM

For 31 Flavors, there are lots of good suggestions embedded in the contest rules.

One statement that " It may be useful to call CQ in BPSK 31, indicating which mode variant will follow..." might be amplified with the following additional statement:

"If your software supports RSID (Reed Soloman Identifier), you might want to ensure that is enabled for this sprint.  To identify the mode being transmitted the RSID can be transmitted before (and after) the data. Using this identifier the receiving software can automatically switch to the proper mode for decoding. The assigning of these identifiers to new modes is coordinated to ensure inter-operation between programs.  At least seven sound card-digital-modem programs support this standard.

  • PocketDigi
  • DM780
  • Multipsk
  • Fldigi
  • AndFlmsg


RSID operates by sending a short burst of a specific modulation before the data signal, which can be used to automatically identify over 272 digital modes. This burst consists of a 10.766 baud 16-tone MFSK modulation where 15 tones/symbols are sent. The burst occupies 172 Hz of bandwidth and lasts for 1.4 seconds.

Enabling RSID might save you manually cycling through various modes guessing which one is in use!  Some programs, like Fldigi, allow you to select which modes you would like to transmit RSID for.  This allow you to inhibit RSID on BPSK-31 (which is pretty obvious on the waterfall) but enable it on other modes (such as BPSK-63) if desired."

Just a suggestion to make life easier.

Mike W4BZM



Using the RSID is a great  idea.  Just make sure if you make a contact to turn the RXID off during the contact because if another RSID is received while you're in the contact your rig might switch to a different mode and you'll loose the contact..

Bill Williams

That will not happen in DM780.  You must click the little notice box for the software to change frequency and mode.