In amateur radio, QRP operation means transmitting at reduced power levels while aiming to maximize one's effective range while doing so. The term QRP derives from the standard Q code used in radio communications, where "QRP" and "QRP?" are used to request, "Reduce power," and ask "Should I reduce power?" respectively. The opposite of QRP is QRO, or high-power operation. Amateur radio station with modern solid-state transceiver featuring LCD and DSP capabilities Amateur radio, often called ham radio, is both a hobby and a service that uses various types of radio communications equipment to communicate with other radio amateurs for public service, recreation and self-training. ... The Q code is a standardized collection of three-letter message encodings, all starting with the letter Q, initially developed for commercial radiotelegraph communication, and later adopted by other radio services, especially amateur radio. ... QRO In amateur radio, a Q code meaning increase power level. The opposite of QRP. In modern ham radio use, QRO is synonymous with high power. The typical station transmitter for high frequency use has 100 watts output. ...

Philosophy

Most amateur radio operators use between 50 and 150 watts of power. QRP enthusiasts contend that this isn't always necessary, and doing so wastes power, increases the likelihood of causing interference to nearby televisions, radios, and telephones and, for United States' amateurs, violates an FCC Part 97 rule, which states that one must use "the minimum power necessary to carry out the desired communications." Electromagnetic interference (or EMI, also called radio frequency interference or RFI) is a (usually undesirable) disturbance caused in a radio receiver or other electrical circuit by electromagnetic radiation emitted from an external source. ... A telephone handset A touch-tone telephone dial Telephone The telephone or phone (Greek: tele = far away and phone = voice) is a telecommunications device that transmits speech by means of electric signals. ... FCC redirects here. ...

Practice

There is not complete agreement on what constitutes QRP power. While most QRP enthusiasts agree that for CW, AM, FM, and data modes, the transmitter output power should be 5 watts (or less), the maximum output power for SSB (single sideband) is not always agreed upon. Some believe that the power should be no more than 10 watts peak envelope power (PEP), while others strongly hold that the power limit should be 5 watts. QRPers are known to use even less than five watts, sometimes operating with as little as 100 milliwatts or even less. Extremely low power – 1 watt and below – is often referred to by hobbyists as QRPp. 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting telegraphic information, using standardized sequences of short and long elements to represent the letters, numerals, punctuation and special characters of a message. ... Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. ... In telecommunications, frequency modulation (FM) conveys information over a carrier wave by varying its frequency. ... For other uses, see Data (disambiguation). ... In telecommunications, modulation is the process of varying a periodic waveform, i. ... Antenna tower of Crystal Palace transmitter, London A transmitter (sometimes abbreviated XMTR) is an electronic device which with the aid of an antenna propagates an electromagnetic signal such as radio, television, or other telecommunications. ... Transmitter power output (TPO) is the actual amount of power (in watts) of RF energy that a transmitter produces at its output. ... For other uses, see Watt (disambiguation). ... Single-sideband modulation (SSB) is a refinement of the technique of amplitude modulation designed to be more efficient in its use of electrical power and bandwidth. ... Peak envelope power is the average power supplied to the antenna transmission line by a transmitter during one radio frequency cycle at the crest of the modulation envelope, under normal operating conditions. ...

Communicating using QRP can be difficult since the QRPer must face the same challenges of radio propagation faced by amateurs using higher power levels, but with the inherent disadvantages associated with having a weaker signal on the receiving end, all other things being equal. QRP aficionados try to make up for this through more efficient antenna systems and enhanced operating skills. Radio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. ... A Yagi-Uda beam antenna Short Wave Curtain Antenna (Moosbrunn, Austria) A building rooftop supporting numerous dish and sectored mobile telecommunications antennas (Doncaster, Victoria, Australia) An antenna is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. ...

QRP is especially popular with CW operators and those using the newer digital modes. PSK31 is a highly efficient, narrow-band mode that is very suitable to QRP operation.^[1][2] 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting telegraphic information, using standardized sequences of short and long elements to represent the letters, numerals, punctuation and special characters of a message. ... PSK31 or Phase Shift Keying, 31 Baud is a digital radio modulation mode, used primarily in the amateur radio field. ...

Equipment

Many of the larger, more powerful commercial transceivers permit the operator to lower their output level to QRP levels. Commercial transceivers specially designed to operate at or near QRP power levels have been commercially available since the late 1960s. In 1969, American manufacturer, Ten-Tec, produced the Powermite-1 (PM-1). This radio was one of Ten-Tec's first assembled transceivers. (The MR-1 was available, and it was essentially the same radio, albeit in kit form.) This radio featured modular construction (all stages of the transceiver were on individual circuit boards): the transmitter was capable of about one or two watts of RF, and the receiver was a direct-conversion unit, similar to that found in the Heathkit HW-7 and HW-8 lines. Many amateurs became quite adept at QRP'ing through their use of these early, trend-setting radios. As QRP has become more popular in recent years, radio manufacturers have introduced radios specifically intended for the QRP enthusiast. Popular US models include Elecraft K2 and K1, the Yaesu FT-817, the Icom IC-703, and the Argonaut V from TenTec.^[3] Popular German QRP transceiver kits include the Moskita, Sparrow, Hegau, Hohentwiel, Tramp-8 CW and others.^[4] HFPack enthusiasts operate QRP radios on the HF bands in portable modes, usually carrying the radios in backpacks, with whip antennas. Motorola HT1000 hand-held two-way radio A two-way radio is a radio that can both transmit and receive (a transceiver), unlike a broadcast receiver which only receives content one way. ... Part of a 1983 Sinclair ZX Spectrum computer board. ... In telecommunication, a direct-conversion receiver (DCR), also known as homodyne, synchrodyne, or zero-IF receiver, is a radio receiver design that demodulates incoming signals by mixing it with a local oscillator signal synchronized in frequency to the carrier of the wanted signal. ... Heathkits were products of the Heath Company, Benton Harbor, Michigan. ... It has been suggested that Yaesu FRG-7, Yaesu ft-107m, Yaesu FT-847, Yaesu VX-7R, and others be merged into this article or section. ... ICOM Incorporated ) (TYO: 6820 ) is an international manufacturer of radio transmitting and receiving equipment, founded in 1954 by Tokuzo Inoue. ... High frequency (HF) radio frequencies are between 3 and 30 MHz. ... A band is a small section of the spectrum of radio communication frequencies, in which channels are usually used or set aside for the same purpose. ... An amateur radio station is a facility equipped with the apparatus necessary for carrying on radiocommunications in the Amateur Radio Service. ... The simplest form of backpack (also rucksack or knapsack) is a cloth sack carried on ones back and secured with two straps that go over the shoulders and below the armpits. ... A whip antenna is an antenna with a single driven element and a ground plane. ...

Some QRPers prefer to construct their equipment from kits or homebrew it from scratch. Homebrew is an Amateur radio slang term for home-built, noncommercial radio equipment. ...

Contests and awards

There are specific operating awards, contests, clubs, and conventions devoted to QRP enthusiasts. An award is something given to a person or group of people to recognize excellence in a certain field. ... Champions of the 2002 World Radiosport Team Championship (WRTC), Helsinki, Finland. ... Clubs (♣) is one of the four suits found in playing cards, marked with a black trefoil; the term is translated from the Spanish basto. ... Metro Toronto Convention Centre, late 2004. ...

In the USA, the November Sweepstakes, June and September VHF QSO Parties, January VHF Sweepstakes, and the ARRL International DX Contest, as well as many major international contests have designated special QRP categories. For example, during the annual ARRL's Field Day contest, making a QSO (ham-to-ham contact) using "QRP battery power" is worth five times as many points as a contact made by conventional means. The American Radio Relay League (ARRL) was founded in May 1914 by Hiram Percy Maxim. ... The American Radio Relay League (ARRL) was founded in May 1914 by Hiram Percy Maxim. ... Field Day is the name of several different amateur radio contests. ...

Typical awards include the QRP ARCI club's "thousand-miles-per-watt" award, available to anyone presenting evidence of a qualifying contact. QRP ARCI also offers special awards for achieving the ARRL's Worked All States, Worked All Continents, and DX Century Club awards under QRP conditions. Other QRP clubs also offer similar versions of these awards, as well as general QRP operating achievement awards.^[5] Worked All States, or WAS, is an Amateur Radio award given to those who successfully complete two-way amateur radio communications with each of the 50 United States of America. ... Worked All Continents, or WAC, is an Amateur Radio award given to those who successfully complete two-way amateur radio communications with each of the 6 continental areas of the world. ... The DX Century Club, or DXCC, is an award (and registered trademark) granted by the ARRL, given for contacting by means of amateur radio with other operators in at least 100 entities and confirming those contacts by way of a QSL card, or via the ARRLs Logbook of the...

See also

• Amateur radio homebrew

Homebrew is an Amateur radio slang term for home-built, noncommercial radio equipment. ...

Notes

1. ^ http://www.njqrp.org/whyqrp/whyqrp.htm
2. ^ http://www.nsradio.org/QRP.ppt
3. ^ http://www.nsradio.org/QRP.ppt
4. ^ http://www.qrpproject.de/UK/GermanKits.html
5. ^ http://www.arrl.org/tis/info/qrpwhtwy.html

External links

• QRP WebRing Home
• QRPedia wiki
• American QRP Club
• Four State QRP Group
• GQRP Club
• New Jersey QRP Club
• North Georgia QRP Club
• Flying Pigs QRP Club International
• North American QRP CW Club
• Northern California QRP Club
• QRP Amateur Radio Club International
• The Eastern PA QRP Club