Single Op, Two Radios (SO2R) What…..Why…….When Where… And….How By: Jim Jordan, K4QPL

PREFACE TO SO2R POWER POINT PRESENTATION   This power point presentation is designed for a live group, with questions, comments, asides, and all the other things that keep something from being just dry reading. Even the original presentation suffered from Murphy’s Law when our regular meeting place had double booked our room and I had to shout over the noise from the regular bar patrons. Remember, this is an outline. If you have questions, comments, different opinions, or would like more info on a specific topic, please don’t hesitate to contact me. Email is the best way, K4QPL@NC.RR.COM Using a second radio is not something that you “can” or “can’t” do. It’s probably easier, and definitely less dangerous, than driving a car while talking on a cell phone. And the analogy is a good one for other reasons. While you may be OK having a casual conversation on the cell phone while driving in light traffic, a serious conversation in heavy traffic should  

prompt you to either hang up the phone or pull off the road prompt you to either hang up the phone or pull off the road. The same rules apply to using a second radio in a contesting situation. As you become more confident in your skills, you may increase your workload and use the second radio more often in a contest. But there’s nothing that says you have to. Many contesters, who are very good operators, do not do SO2R. For some, they’ve reached a point where they are comfortable with what they are doing and couldn’t be bothered with it. Sort of the “old dogs, new tricks” idea. Others have tried it and found that for various reasons it doesn’t work for them, or maybe theway they process information makes it more difficult. (This is a real factor—I recently took a course in which the instructor outlined these differences which have nothing whatsoever to do with intelligence.) Others simply fear that they will make a mistake and sound “liddish”. Well, that can happen. Who never fell off their bicycle while learning? And the very nature of SO2R operations sometimes causes inconvenience and sounds like you’ve gone to sleep,  

or your keyer is cutting out when heard from the perspective of the ham on one band only.   Overload does happen. No matter how slow your run is before, the moment you commit to a qso on the other radio your run frequency will be attacked by QSB, QRN, a 4 call pileup and a poacher trying to take your spot! The only response is to realize that if that’s the worst thing to happen in your life, just praise your favorite god or saint and do the best you can. Another thing to remember is that SO2R is NOT the greatest thing since sliced bread. It is just one more tool in your contesting kit for use under certain conditions. It’s mostly used to best advantage to pick up multipliers without stopping a good run.  So my challenge is, even if you say that SO2R is not for you, go through the presentation, make a few adjustments in your station, and then, in the privacy of your own shack, when a contest gets slow, sneak out and drop your call on another run station with your second radio. See if the rush and the satisfaction doesn’t make you come back for more!

  In choosing from available equipment for SO2R, the preferred S&P radio should be: your QRP radio to avoid overload your separate tx and rx for easier tuning your better LP transceiver your not as good LP transceiver. WHAT….. Contesting setup with capability to listen on two frequencies simultaneously and rapidly switch between them for transmitting. Contacts are logged in sequence regardless of radio used. Two radios do NOT transmit at the same time. Casual observer may think otherwise. Not the same as dual receiver or two VFO radio. (Second Rx can’t listen while transmitting). Can be set up for cw or ssb

WHY….. Gathering info on other bands while keeping a run going. Easier with second radio than dual receive/VFO radio. Maintaining a run while finding and working multipliers. Increasing overall rate by S&P when run rate is below max capability. Probable SO2R points increase best for LP where separate run and S&P rates are slower. QRP run is problem Running two slow bands (Dueling CQ’s) MORE FUN, MORE POINTS!

WHEN…… ONLY when you have spare time. Normally not at beginning of test. If you are working stations at a good rate, don’t be distracted by trying to do SO2R. When the band you can run on is unlikely to have the multipliers you need. 20 may be your best run/rate band, but you suspect VY1JA is on 10. When the run rate slows, but there’s nowhere else to go. (End of contest doldrums)

WHERE…… NOT on your run band. Major QRM problems ….and you may fry your second receiver. It can be done, but risky, especially HP. OK for QRP. Avoid harmonics. If you expect to S&P a higher band than your run radio, choose a higher run frequency. Example: S&P 40. Run 3512 (7024) Bad; Run >3540 (7080+) Good. Preview. Run 20, preview 40 as 20M skip goes out. 40M SO2R S&P. Cleanup. Move run to 40, S&P 20 until it dies. Then preview 80. Use preview and cleanup to establish run on a band BEFORE the mob arrives and without losing QSO’s.

How…..(Equipment) Basic Intro: Low Power. Second radio, separate antenna, software for SO2R mode, mono/stereo “Y” and stereo headset. NR type great. 2 paddles/mikes or switches (unless you use software and keyboard). Run with best radio/ants. Basic competitive: Add SO2R antenna switching (SixPak or equivalent) If tribander, add dipoles. Voice keyer or .wav files for SSB. Serious: Add better second radio; both interfaced; a “box” for audio and other switching functions. May need filters or stubs for some bands. Pro: High Power. Filtering (Band pass or Stubs). Monoband gain antennas for 20-10. Consider same band mult hunting (CAUTION).

How….(Software) Most contesting software is SO2R capable. Learn about yours. (Can’t compare or train in this program) General rules: Keep it short, simple, clear Use differential speed in exchanges. CW: Fast: 5NN Slow N C SSB DVK: “Fyny [clearly] November Charlie.” Experiment with length of CQ’s. Try to match with average exchange receive time. If Assisted mode, packet interfaced band map on second radio is GREAT. Just click on the spots. LISTEN to confirm. There are a lot of busted calls out there.

How……(Operating) Practice listening in stereo (two rag chews) Learn the keystrokes. Label the “F” keys and have a short “cheat sheet.” Searching the Help manual during the QSO is not an option! See “Making the First One” below. Keep on doing it. “Practice makes perfect” is a good slogan for SO2R. Use the highest level of equipment (excluding HP) you can afford. The enhancements make SO2R easier, not harder. Go HP only when your station is ready and you’ve minimized the “lid” factor!

How….Making the First One. Choose your opportunity: Run is slow on your radio. No pileups. Mult is strong but doesn’t have pileups. Not too fast. Good op, doesn’t ask for a lot of fills. Pre-logging reduces stress, errors and fills: Write down his call, non-variable info and also pre-enter that into SO2R program if it lets you. Write down time and his number sequence. Update as needed. Rehearse in your mind including fills if needed Mind the store while you plan: Don’t lose run qso’s or lose your frequency

Making the First One, Page 2 Ready, set, GO: Wait for an alignment (your CQ ends just before his and you have no response. This will give you a few extra seconds) Drop your call (Initiate the software SO2R sequence) When he comes back, block everything else out of your mind and ENTER HIS EXCHANGE. Send his exchange and wait for acknowledgment. Send fills if necessary. ONLY THEN listen to run radio and see what’s happening there. HOOOOOOOOO AHHHHHH!

Resources 1 SO2R operating position at K4QPL. No, not left handed. Many CW operators tune radios with their left hand. Leaves right hand free for paddle, etc. Good for SO2R.

Resources 2 Six Pak SO2R Remote Antenna Switch Ameritron Remote (Daisychain 2x40M) K4QPL homebrew interface, audio, and signaling SO2R box.

Resources 3 Screen during NC QSO Party using TR-Log in SO2R mode. Note clear radio identification—band in black box, frequency highlighted, and red “Radio B” marker. When other radio is active all ID’s change and the radio box turns green. Also note “Dueling CQ” warning and alternating 40M and 20M QSO’s in log.

Resources 4 VISUALIZE TWO QSO’S IN CW SO2R. BOLD = your transmissions Underline = other stations Run Radio                                S&P Radio CQ TEST K4QPL                 Tuning for new ones Listen to Run radio                                   F5IN     F5IN 5NN NC                            Listen to Run radio 5NN 300 TU K4QPL                         Tuning (you come across TM0A CQ TEST K4QPL                 K4QPL  (when he stands by) CQ Test K4QPL optional               K4QPL 5NN100 interrupt CQ if necessary           TU 5NN NC when he is done CQ Test K4QPL                 TU TMOA QRZ                 Listen to Run radio              Tuning (Suggestions for this screen courtesy N4ZR)

Resources 5 ICE Band pass Filter www.iceradioproducts.com/ Array Solutions Six Pak www.arraysolutions.com W1GEE interface cable at www.sarrio.com USB to 4 serial ports by www.cooldrives.com Single USB CAT interface from www.westmountainradio.com W3NQN single band filters From Array Solutions.