Walk And Chew Gum At The Same Time

Now I think that I’m a fairly coordinated guy. I can play guitar and know my way around a piano keyboard. It’s no problem for me to pat my head and rub my stomach at the same time and I can even make the Spock “Live Long and Prosper” sign…with both hands. But this takes it to a whole new level…

From Wikipedia …

“Single operator two radios (SO2R) is an operating practice employed by some competitors in the sport of amateur radio contesting. By using two transceivers attached to separate antennas, competitors can listen to one amateur radio band while transmitting on another. This capability enables the operator to more efficiently locate other amateur radio stations participating in the competition with which to make contact and score points.”

While operating the 2012 SSB Sweepstakes, I often thought how nice it would be to have a second radio to use for searching bands that I wasn’t Cqing on. When the opportunity came to upgrade to a Yaesu FDX-5000 last March, I made the decision to keep my Icom IC-746Pro as a second radio for an SO2R setup. Over the past year I’ve accumulated, mostly from the used market, the other equipment needed.

Array Solutions SixPak Antenna Switch - This allows any antenna (up to 6) to be fed to either of 2 radios. There is protection built in that prevents both radios from selecting the same antenna.

TopTen Devices DX Doubler - The device takes inputs from the microphone, keyer and footswitch. The outputs go to each of the 2 radios. Control of receiving and transmitting is done either manually or through the logging software

Dunestar 600 Bandpass Filters - These 6 band units are installed between each radio and the incoming antenna lines. Control is either manual or through Band Decoders. They are designed to prevent overloads to each radio’s front end from the other radio’s transmitted signal.

I spent a couple of days getting all the required cables made and the equipment in the right place. A dummy load on each radio made sure I wasn’t sending RF from and to places unknown. All the testing was successful. Manual operation was pretty straight forward. The DX Doubler has a Receive side and a Transmit side. When the switches are set to Radio 1, Rcve and Xmit are Radio 1. Switches set to Radio 2. Rcve/Xmit on Radio 2. In addition, the Receive side has a Both position. When set there you hear Radio 1 in the Left Ear and Radio 2 in the Right Ear. Piece of cake…

Auto operation gets a little more complicated. The N1MM Contest Logger fully supports the hardware. And although there are a lot of keystrokes and Macros available for SO2R operation, there were just a handful that I absolutely would need to memorize.

Tilde ~ Toggles receive audio from one radio in each ear to the transmit radio in both ears

Back Slash \ Moves keyboard focus between each radio’s logging window without changing the Transmit state. This allows you to pre-enter a call for the S & P radio

Control Right Arrow/Left Arrow Moves Transmit between the 2 radios

So here is how it works…in theory…

From the N1MM website…

“Single Operator 2 Radio (aka SO2R) is an operating technique that when done properly, can add many extra QSOs and multipliers to your log. This is accomplished by increasing your efficiency during slow times, for example, when you are CQing on one radio, but getting few answers. Efficiency is increased by listening on a 2nd radio while you are transmitting on the 1st radio. On the 2nd radio you are scanning the bands for needed QSOs and multipliers. If you find a new station to work on the 2nd radio, you leave it staged on the 2nd Entry Window until you get a free moment to work this station. Even adding a few QSOs an hour will greatly boost your score. “

And step - by - step…

1) Each radio set to a different band/antenna

2) Radio 1 audio in left ear. Radio 2 audio in Right

3) Transmit on Radio 1 and Cqing (preferably with an automated CQ message)

4) Keyboard focus is on Radio 1 logging window

4) Tuning the Radio 2 VFO looking for needed stations/multipliers

5) You get an answer to your CQ. Log call, exchange and continue Cqing

6) A needed call is found on Radio 2. Back slash to enter call in Radio 2 logging window

7) Another answer to your CQ. Back Slash moves keyboard back to Radio 1 logging. Log call. Call CQ

8) No one answers CQ. Needed station is still on Radio 2. Control Right Arrow moves Rcve/Xmit to Radio 2. Call station, complete exchange and log it.

9) Control Left Arrow moves Transmit back to Radio 1. Hit F1 key to begin calling CQ again

10) Back to Number 3 and do it all again.

Since everything nowadays comes with a disclaimer…here are some caveats.

Don’t try this when your run rate is high. There is just not enough time.

Don’t spend too much time on the S & P radio and risk losing your CQ frequency.

Your mileage may vary. Side effects include…

I operated SO2R during the NAQP SSB contest. Although I only made 15 2nd radio Qs, I gained a lot of experience and also a lot of respect for the guys who do this so well.

This is going to take a LOT of practice...

Below are pictures of the equipment and software setup that I used.


Radio 1 Left - FTDX-5000 Radio 2 Right IC-746Pro SO2R Interface Center TopTen DX Doubler
Antenna and Bandpass Filter Switches on Right (Out of frame)


Bottom Monitor - N1MM Setup showing Radio 1 and 2 Logging windows and band maps.
Super Check window and Log window


Top Monitor - N1MM Setup showing Multiplier and Score Summary windows

Doug - K1ZO