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. 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!
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 2010. 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
CQ TEST K4QPL
Listen to Run radio
F5IN
F5IN 5NN NC
Listen to Run radio
5NN 300
TU K4QPL
CQ TEST K4QPL
CQ Test K4QPL optional
interrupt CQ if necessary
CQ Test K4QPL
Listen to Run radio
S&P Radio
Tuning for new ones
Tuning (you come across TM0A
K4QPL (when he stands by)
K4QPL 5NN100
TU 5NN NC when he is done
TU TMOA QRZ
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
W3NQN single band filters
From Array Solutions.
USB to 4 serial ports by
www.cooldrives.com
Single USB CAT interface from
www.westmountainradio.com