Improvements in RTTY Reception and Decoding Larry Gauthier K8UT May 18, 2013
2 Hamvention RTTY Forum Agenda 2Tone Adaptive RX Using Both in a Contest Short video (time permitting)
3 Introduction - About K8UT Licensed since 1968 Operating RTTY since 2001 Awards - DXCC - WAS - WAZ RTTY operation - FSK - Typically SO1V / SO2V Software Prejudices - DX4Win for DXing - N1MM Logger for Contesting - MMTTY and 2Tone Major RTTY Contest Achievements - Participated in many - 1 st Place in none Station Configuration - One transceiver, one amplifier, one tower a little pistol Antennas - Vertical and dipole on 80 meters - Dipole on 40 meters - 2 element quad on 20 10 meters Other stuff - Member of the N1MM Logger Dev Team - Webmaster for N1MM Logger website - Operated W8SH at MSU with Dave Sumner
4 What is 2Tone? Just another RTTY software program Many others - MMTTY, Fldigi, WinWarbler, MMVari Only decodes RTTY signals (like MMTTY) Only a RTTY Demodulator Not a stand-alone RTTY application like MMTTY Must run beneath a logging program Supported programs include: N1MM Logger, Write Log, DXLabs WinWarbler, Logger32 Freely available from many sites (www.rttycontesting.com) Still undergoing active development Updated often by David, G3YYD
5 K8UT s Quick Comparison MMTTY 119 Controls (approximately) 2Tone 8 Controls And besides it doesn t operate FSK, which for me was a non-starter
6 But - Hams Started Using 2Tone With Rave Reviews 2Tone is now my main decoder. I used it with WriteLog this weekend with great success. EA RTTY (AA5AU) I setup six decoder windows, three on each receiver... 2Tone was superior. NA Sprint (W0YK) Used 2Tone for the first time in a second cloned window... Was very impressed. EA RTTY (8P6SH) Found 2Tone to work great on the tough ones. EA RTTY (K5ND) 2Tone worked really well and saved a lot of AGN? request. NAQP RTTY (AI9T) Time to start drinking the 2Tone Kool-Aid!
7 A Scientific Comparison What would the testing protocol be? Multiply MMTTY s 119 controls Times 2Tone s x 8 controls ==== 952 combinations + strong / weak signals + QRM / no QRM + normal / flutter conditions 952 combinations combinations Not gonna happen
8 A More Practical Approach Conducted an On-Line 2Tone Adoption Survey Ran from April 11 to April 30, 2013 with 150 responses Good mix of Avid, Average, and Infrequent contesters One-third of the respondents Had never heard of 2Tone or, Had not tried 2Tone yet or, Had not made a decision Number of RTTY contests per year Thanks to those who completed the survey!
9 A More Practical Approach Build a Grid with the Key Differentiators No QRM Heavy QRM Strong Signal?? Weak Signal?? Make recommendations that hams can duplicate in their shacks
10 A More Practical Approach Build a Grid with the Key Differentiators Who cares? No QRM Heavy QRM Contesters DXPeditions Strong Signal?? Weak Signal?? Everybody Make DXers recommendations that hams can duplicate in their shacks
11 A More Practical Approach Survey Question: Under what conditions is MMTTY better? 2Tone better? Both are equal? Strong Signal No QRM? Heavy QRM? Weak Signal??
12 A More Practical Approach Survey Question: Compare Features. When is MMTTY better? 2Tone better? Both are equal? AFC Squelch
13 A More Practical Approach Survey Question: What was your decision?
14 Recommendations 2Tone and MMTTY are excellent RTTY programs But that does not mean that they are identical If you can only operate one RTTY decoder 2Tone is the best choice If you can operate two (or more) interfaces Operate with both 2Tone and MMTTY Exploit the advantages of each program Based on band/signal conditions Need for AFC, Squelch, complex filters
15 2Tone Summary 2Tone Is an excellent RTTY demodulator Should definitely be in your RTTY contest toolbox Best when used in concert with MMTTY Bottom line: If you aren t already, you should be drinking that 2Tone Kool-Aid
Improvements in RTTY Reception and Decoding Larry Gauthier K8UT But wait! There s more
17 Hamvention RTTY Forum Agenda 2Tone Adaptive RX Using Both in a Contest Short video (time permitting)
18 Introduction About K8UT Station Configuration One transceiver, one amp, one tower, one multi-band antenna Just a Little Pistol in the Big Gun versus Little Pistol battle As such, I operate a lot of Search and Pounce in contests
19 ARRL RTTY Contest 2013 Experienced an Epiphany during the contest With each S&P QSO, I was turning the Icom s TPF filter On, then Off
20 ARRL RTTY January 2013 Experienced an Epiphany during the contest and On, then Off and On, then Off and On, then Off
21 ARRL RTTY January 2013 Duh! Couldn t the computer be doing this for me?
22 Adaptive RX Design seemed obvious and easy Develop software to Monitor VFO traffic from the radio Detect when the VFO frequency is changing Toggle between wide and narrow filters when VFO=static versus VFO=tuning It s just a SMOP!* *SMOP = Small Matter of Programming
23 Adaptive RX Implementation was a little more complicated Select different filters for RTTY versus CW Control both the IF filters and the APF/TPF filters Ignore minor QSY changes when fine-tuning a station Adjust the delay when deciding if the VFO is stationary Some software terminology Tuning and Stationary states QSY Sensitivity for fine-tuning, in Hz QSY Dwell Time for filter transitions, in tenths of seconds
24 Adaptive RX Is this a Concept or a Product? well it s both! If you are an Icom owner, it s a product Works with HRD, DXLabs, DX4Win, N1MM Logger, WinTest Documentation and free download from www.k8ut.com Filename: CI-Vfilter.zip Perhaps a couple of dozen hams have installed it (?) I use it constantly for both DXing and Contesting
25 CI-Vfilter.EXE Config screenshot
26 CI-Vfilter.EXE But CI-Vfilter is still Rough Around the Edges Crashes when com ports are misconfigured Requires an additional serial port Polling rate defined by your logging software Likely fixes / enhancements Eliminate the need for a second serial port (act like a router) Change from protocol injection to protocol routing Extend the program beyond Icom s CI-V protocol Elecraft, Yaesu, Kenwood If you try it, comments and suggestions are welcome
27 Hamvention RTTY Forum Agenda 2Tone Adaptive RX Using Both in a Contest Short video (time permitting)
28 Using Both of These Tools Screenshot from ARI RTTY Contest, May 2013 S&P in SO1V/2d Single Op 1 VFO with Diversity in VFO-B Left side of monitor N1MM Logger s VFO-A Entry and Bandmap Windows 2Tone and MMTTY graphics and text displays Narrow RTTY filters via CI-Vfilter.exe (stationary) Right side of monitor N1MM Logger s VFO-B Entry and Bandmap Windows 2Tone and MMTTY graphics and text displays Wide RTTY filters no CI-Vfilter.exe involvement CI-Vfilter Diversity enabled VFO-B tracking VFO-A
Using Both of These Tools 29
30 Using Both of These Tools Moderate (S5) signals, with no QRM All of the decoders printed the exchange correctly
31 Using Both of These Tools Very weak (S0) signals, with adjacent frequency QRM None of the decoders printed the entire exchange correctly
32 In Summary 2Tone and CI-Vfilter are just tools, but they could Increase QSO rates Minimize busted calls/exchanges Avoid those AGN? AGN? repeat requests Eliminate unnecessary repetitive tasks Reduce operator fatigue, increase enjoyment Improve your contest score and operating experience
33 Short Video Screencast Video RTTY SO1V, MMTTY decoder (30 seconds) RTTY SO1V/2d, MMTTY and 2Tone decoders (60 seconds) CW SO1V (30 seconds)