Single operator two radios (SO2R) is an operating practice employed by some competitors in the sport of
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
contesting
Contesting (also known as '' radiosport'') is a competitive activity pursued by amateur radio operators. In a contest, an amateur radio station, which may be operated by an individual or a team, seeks to contact as many other amateur radio stati ...
. By using two
transceiver
In radio communication, a transceiver is an electronic device which is a combination of a radio ''trans''mitter and a re''ceiver'', hence the name. It can both transmit and receive radio waves using an antenna, for communication purposes. The ...
s attached to separate
antennas
In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies a ...
, competitors can listen to one
amateur radio band
Amateur radio frequency allocation is done by national telecommunication authorities. Globally, the International Telecommunication Union (ITU) oversees how much radio spectrum is set aside for amateur radio transmissions. Individual amateur st ...
while transmitting on another. This capability enables the operator to more efficiently locate other
amateur radio station
An amateur radio station is a radio station designed to provide radiocommunications in the amateur radio service for an amateur radio operator. Radio amateurs build and operate several types of amateur radio stations, including fixed ground sta ...
s participating in the competition with which to make contact and score points.
Description
Radio contests typically have different operator categories for Single or Multiple people using a single station in the contest. SO2R is an operating technique used by some competitors in the single-operator categories in contesting. While single-operator means that only one transmitter can be active at any time, in SO2R, a single station operator uses two radios to listen simultaneously to two different
radio frequencies
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper ...
. When the two radios are on different radio bands, an operator can be listening to one radio while the other is transmitting. This can result in increased operating efficiency, as the operator can always be looking for new contacts to increase his or her score. SO2R operation can be a challenge to learn and requires practice to achieve proficiency.
While SO2R offers the advantage of listening to the second radio while the first is transmitting, this added activity can also become a challenge to the operator. There are some that consider SO2R use in
HF contests to be controversial. The critics feel that the extra expense, complexity, and improved performance that can be achieved from SO2R operation merits the separation of SO2R operations into a distinct competitive entry class from other single operators. While no major contests have yet done this, some will list individual scores in contest results with an SO2R designation where the station self-reports that SO2R was used.
SO2R has now been in use for over ten years, becoming a widely accepted practice. While SO2R formalizes the practice of using multiple receivers during a contest, this has always been accepted in the rules of radio contests. Several manufacturers now offer hardware and software specifically aimed at the SO2R operator.
Callsign
SO2R is also a valid amateur radio
callsign
In broadcasting and radio communications, a call sign (also known as a call name or call letters—and historically as a call signal—or abbreviated as a call) is a unique identifier for a transmitter station. A call sign can be formally assigne ...
issued to an active contest station in
Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...
.
[SO2R call sign listing on QRZ.com](_blank)
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References
{{reflist
*Healy, Rus K2UA (2001).
"Single-Operator Contesting with Two Radios"
Retrieved Dec. 7, 2005.
*Tyree, Tree N6TR (2000).
"TR LOG Two Radio Contesting Tutorial"
Retrieved Dec. 7, 2005.
*Nunes, José CT1BOH (2006)
Retrieved Jul. 5, 2006.
Radiosport