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Glossary: Q codes, abbreviations and terms

The abbreviations that all hit you at once in your first QSO, and the terms you look up while putting up your first antenna. Kept short, for looking things up rather than reading through.

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Q codes

Three letters that replace a whole sentence in telegraphy. With a question mark they are a question, without one a statement. The most common ones are used in voice operation too.

QRA
name of my station
QRB
distance between two stations
QRG
exact frequency
QRL
I am busy, the frequency is in use
QRM
interference from other transmitters
QRN
atmospheric noise, static crashes
QRO
increase power, high power
QRP
reduce power, operating with low power
QRQ
send faster
QRS
send more slowly
QRT
stop operating, closing down
QRU
I have nothing for you
QRV
I am ready
QRX
please wait
QRZ
Who is calling me?
QSA
signal strength, scale 1 to 5
QSB
varying signal strength, fading
QSL
acknowledge receipt, also the confirmation card
QSO
radio contact
QSP
relay a message
QSY
change frequency
QTC
I have a message
QTH
Location
QTR
exact time

Abbreviations in telegraphy

What goes over the air all the time in CW and digital modes. Many abbreviations come from English maritime radio.

CQ
general call to all stations
DE
from, this is
K
end of transmission, over to you
KN
end, but only the station called should answer
AR
end of message
AS
wait a moment
BK
break in mid-transmission
SK
end of contact
CL
closing down the station
R
all received
RST
report: readability, strength, tone
OM
old man, male radio amateur
YL
young lady, female radio amateur
XYL
wife
ES
and
HR
here
UR
your
PSE
please
TNX
thanks
FB
fine business, good, great
HW?
How do you copy me?
WX
weather
ANT
antenna
PWR
power
RIG
radio, transceiver
AGN
again
CFM
confirm
CUL
see you later
GA / GE / GM
good afternoon, good evening, good morning
HI
laughter
73
best regards
88
love and kisses, customary towards a YL
55
good luck, common in contests
Abkürzungszahlen
Shortened digits in contests: T for 0, N for 9, A for 1, E for 5. 5NN means 599, 1T7 means 107
Rauschsperre (CW)
A CW decoder only starts writing when several strong tones arrive with real gaps between them. With no signal the text stays empty instead of guessing characters out of the noise

RST report

The report describes how a station is coming in. In SSB only the first two digits are given, in CW all three.

R1 bis R5
Readability: 1 unreadable, 3 readable with difficulty, 5 perfectly readable
S1 bis S9
Signal strength: 1 barely perceptible, 5 fair, 9 very strong
T1 bis T9
Tone in CW: 9 pure tone, lower values hum or sound rough
59 / 599
standard report, in contests often regardless of the actual signal
S9 + 20 dB
above S9 the count continues in decibels, one S unit is 6 dB

Phonetic alphabet

The ITU alphabet is used in radio everywhere, within Germany too. Callsigns are always spelled out when they might not come across clearly.

A B C D
Alfa, Bravo, Charlie, Delta
E F G H
Echo, Foxtrot, Golf, Hotel
I J K L
India, Juliett, Kilo, Lima
M N O P
Mike, November, Oscar, Papa
Q R S T
Quebec, Romeo, Sierra, Tango
U V W X
Uniform, Victor, Whiskey, X-ray
Y Z
Yankee, Zulu
Zahlen
Nadazero, Unaone, Bissotwo, Terrathree, Kartefour, Pantafive, Soxisix, Setteseven, Oktoeight, Novenine (rare in amateur radio, digits are usually just said normally)

Callsigns in Germany

Prefix and digit tell you the purpose and licence class, as laid down in the callsign plan of the Bundesnetzagentur (BNetzA, German regulator), valid from 1 April 2025. Which series are open to you is shown by the finder at /rufzeichenplan.

DB, DC, DD, DF, DG, DH, DJ, DK, DL, DM mit Ziffer 1 bis 9
personal callsigns for class A, plus DA1 and DA2
DO1 bis DO9
personal callsigns for class E, plus DA6; around 8,900 licences (list of 14 September 2026)
DN9
the only series for personal callsigns of class N
DN1 bis DN8
training callsigns: none issued since 24 June 2025, valid until 31 December 2028
DB0, DM0, DO0
repeaters and beacons (DO0 for class E)
DA0, DF0, DK0, DL0
club stations with 2 or 3 letters in the suffix
Suffix mit 1 Buchstaben
club stations only, roughly DQ0A to DR9Z, for up to 5 years
Sonderrufzeichen
club station with 4 to 7 characters in the suffix for a special occasion, one year at most
DP
club stations, repeaters and studies at an extraterritorial location (DP0 to DP2), DP8 also without
DR1 bis DR3 (KSB)
club stations for members of the emergency services (BOS), only for emergencies, disasters and exercises
DR4 bis DR6 (KSO)
club stations of emergency communication groups; no contests, /Ueb during exercises
PZ, KS
personal assignment, assignment for a club station
/p
portable: a handheld or temporarily fixed station
/m, /mm, /am
mobile in a land vehicle or on inland waters, maritime mobile at sea, aeronautical mobile
/T
training operation (trainee), mandatory; goes before /p or /r, so /Tp, /Tr
/r
remote operation, optional
DL/… und DO/…
short-term licence for foreign radio amateurs not resident in Germany, class A or E, for up to three months

Law and administration

The terms that come up in the licence exam and afterwards in letters from the authorities.

AFuG
Amateurfunkgesetz (German Amateur Radio Act), covers purpose, licensing and supervision
AFuV
Amateurfunkverordnung (AFuV, German amateur radio regulations), covers the details: classes, frequencies, power
BEMFV
German ordinance on the verification procedure for protection against electromagnetic fields
26. BImSchV
sets the limits for electromagnetic fields
Anzeige
Anyone transmitting more than 10 W EIRP has to notify the Bundesnetzagentur of the station
Rufzeichenzuteilung
certificate with callsign and class, issued after you pass the exam
Klasse N
entry-level class since 2024: 10 m, 2 m and 70 cm with low power
Klasse E
intermediate class: 160 m, 80 m, 15 m, 10 m and the VHF/UHF bands
Klasse A
full privileges on all amateur bands
EMV-Beitrag
annual fee charged by the Bundesnetzagentur
Selbsterklärung
proof under the BEMFV that the limits are met at your location

Regulation and radio policy

Who allocates frequencies, approves equipment and sets limits: the bodies and abbreviations that turn up in the cases under /funkpolitik, from the world radio treaty to the federal law gazette.

ITU
International Telecommunication Union of the United Nations in Geneva, divides the spectrum into services worldwide
WRC
World Radiocommunication Conference of the ITU, meets roughly every four years and amends the Radio Regulations; the next one is in 2027
CEPT
European Conference of Postal and Telecommunications Administrations, 46 countries, coordinates frequency use in Europe
ECC
Electronic Communications Committee of the CEPT, adopts decisions and recommendations and invites comments
CPG
preparatory group of the CEPT for the World Radiocommunication Conference, sets the common European positions
IARU
International Amateur Radio Union, umbrella body of the national amateur radio societies, represents amateur radio at the ITU and CEPT
BNetzA
Bundesnetzagentur, the German regulator: assigns frequencies and callsigns, runs the exams and investigates interference
DIP
documentation and information system for parliamentary material of the Bundestag and Bundesrat: printed papers, minutes, proceedings
BGBl
Bundesgesetzblatt (federal law gazette), where laws and ordinances are promulgated; only then do they apply
RED
Radio Equipment Directive of the EU (2014/53/EU), governs which radio equipment may be placed on the market; home-built amateur equipment is exempt
SRD
short range devices such as remote keys and sensors, often on 433 MHz and 868 MHz, partly inside the amateur bands
PLC
data transmission over mains wiring (powerline), radiates on HF and spoils reception
CISPR
special committee of the IEC on radio interference, writes the standards with the limits for emissions from equipment
EMVU
environmental compatibility of electromagnetic fields: protecting people from fields, for radio amateurs covered by the BEMFV
KRITIS
critical infrastructure such as power, water and telecoms; in civil protection it is often about radio as a fallback
Konsultation
an authority or body asks the public for comments on a draft, with a deadline; that is where you can have your say

DARC, DOK and awards

If you are active in the society or collect awards, you will run into these abbreviations.

DARC
Deutscher Amateur-Radio-Club, the largest society in Germany
Distrikt
regional level within the DARC, identified by a letter
OV
local club, the local group
DOK
DARC district/club code, for example B37 for the Haßberge local club
Sonder-DOK
identifier for a limited time for a special occasion
QSL-Karte
written confirmation of a contact, traditionally a postcard
QSL-Büro
collects and distributes cards between the societies, cheaper than sending direct
DXCC
award programme of the ARRL, counting entities on its own list
IOTA
Islands on the Air, island groups to collect
WAG
Worked All Germany, contest and award
LoTW
Logbook of the World, electronic confirmation via the ARRL
eQSL, Clublog, QRZ-Logbuch
other electronic confirmation services

Portable programmes

Operating outdoors with a reference as the goal. All programmes work in a similar way: the activator announces themselves, chasers work them, both get points.

POTA
Parks on the Air, national parks and protected areas
SOTA
Summits on the Air, summits with altitude points
WWFF
World Wide Flora and Fauna, protected areas worldwide
GMA
German Mountain Award, mountains and more in German-speaking countries
COTA, LOTA
castles and lighthouses
Aktivierung
operating from a reference, usually with a minimum number of contacts
Spot
online notice that a station is active on a frequency right now
Chaser, Hunter
whoever works the activators

Repeater operation

What has to be set on your radio for a repeater to open, and how to read the details in the lists.

Relais
Automatic station that receives on one frequency and retransmits on another at the same time. With it a handheld covers the whole region.
Ausgabe
The frequency the repeater transmits on, so the one you listen on.
Eingabe
The frequency the repeater listens on, so the one you transmit on.
Ablage
Difference between input and output. Usually −0.6 MHz on 2 m and −7.6 MHz on 70 cm. On the radio it is called shift or duplex.
Simplex
Transmitting and receiving on the same frequency, with no repeater in between.
CTCSS
Quiet continuous tone below the speech that opens the repeater. Common values are 67.0, 77.0 and 88.5 Hz.
TSQL
The radio also checks for the tone on receive and stays silent otherwise. The lists show this as RX/TX.
DCS
Digital version of the tone squelch, given as a three-digit code, for example DCS 023.
1750-Hz-Rufton
Short whistle tone that opens older repeaters. Often a separate button on the radio, sometimes called Call or Tone Call.
Locator
Maidenhead identifier of the location, for example JO50HB. Four characters describe a square of about 111 by 70 km, six characters about 4.6 by 2.8 km.
Talkgroup
Talk group in digital networks such as DMR, comparable to a channel.
Hotspot
Small box at home that connects a digital mode over the internet when no repeater is in range.
Echolink
Linking repeaters and individual stations over the internet.
Bake
Transmitter that sends its identifier continuously. Used to judge propagation.

Modes

From classic voice contacts to methods that still get a contact through when all you hear in the speaker is noise.

CW
telegraphy, a carrier is keyed, goes a long way with very little power
SSB
single sideband, the standard for voice on HF
AM
amplitude modulation: a carrier with two sidebands, twice as wide as the audio, broadcasting on short and medium wave
FM
frequency modulation, common on 2 m and 70 cm and through repeaters
FT8
digital mode with a 15-second cycle, very sensitive, short standard messages
FT4
faster variant of FT8, popular in contests
JS8
derived from FT8, allows free text and relaying
PSK31
narrowband keyboard-to-keyboard mode
RTTY
radioteletype, the oldest digital mode in amateur radio
SSTV
slow image transmission over the voice channel
WSPR
beacon mode with the lowest power, used to observe propagation
C4FM, DMR, D-STAR
digital voice modes, each with its own repeater and network system
POCSAG
paging to pagers, in amateur radio for example DAPNET on 439.9875 MHz; two tones about 9 kHz apart, in short bursts
APRS
position reports and short messages over radio, mostly on 144.800 MHz
Packet Radio
older data transmission with AX.25, partly still running for mailboxes
Winlink
email over radio, often used in emergency communication
EME
Earth-Moon-Earth, the moon as reflector
ATV, DATV
television in amateur radio, analogue or digital

Propagation

Why a frequency gives a different result at midday than at night.

Bodenwelle
follows the earth's surface, carries far on long wave and 160 m
Raumwelle
is refracted in the ionosphere and comes back down far away
D-Schicht
lowest layer at 60 to 90 km altitude, only present by day, mainly absorbs the low bands
E-Schicht
lower layer, present by day, attenuates low frequencies
F2-Schicht
the decisive layer for long-distance contacts on HF
Sporadic E
short-lived clouds in the E layer, open up 6 m and 2 m for long distances in summer
MUF
highest usable frequency for a path
LUF
lowest usable frequency, below it absorption eats the signal
Skip-Zone
dead zone between the end of the ground wave and the first hop
Grayline
twilight line, along which contacts work particularly well
Sonnenfleckenzahl
rough measure of solar activity, a high value helps the high bands
Solarflux, A- und K-Index
indices for solar radiation and disturbances of the earth's magnetic field
Aurora
reflection off the aurora, distorts the audio heavily
Ionosonde
transmitter that sends straight up and measures the height and critical frequency of the layers from the echoes
foF2
critical frequency of the F2 layer at vertical incidence, measured by the ionosonde
MUF(3000)
MUF for a 3000 km hop, roughly three times foF2
hmF2
height of the densest part of the F2 layer, usually 250 to 400 km; the higher it is, the longer the hop
Sprungweite
distance after which a ray reaches the ground again after one reflection; via the F2 layer at most about 4000 km
Abstrahlwinkel
angle above the horizon at which an antenna radiates; low angles hop far, steep ones short
Sekantengesetz
at oblique incidence a ray still turns back at a higher frequency than at vertical incidence: f = foF2 / cos of the angle of incidence
foEs
critical frequency of a sporadic E cloud at vertical incidence; from about 10 MHz 6 m opens over about 2000 km
Kp-Index
disturbance of the earth's magnetic field per three hours, averaged worldwide, 0 to 9; from 5 it counts as a storm
Bz
north-south component of the magnetic field in the solar wind; if it points south (negative) for a long time, it couples to the earth's magnetic field and things get unsettled
Sonnenwind
stream of charged particles from the sun, normally around 400 km/s; fast and dense it disturbs the earth's magnetic field
Flare-Klasse
strength of a solar X-ray flare: A, B, C, M, X, each letter ten times stronger; from M upwards HF drops out briefly on the daylight side
D-RAP
NOAA map showing up to which frequency the D layer currently absorbs 1 dB
Tropo
extended range on VHF/UHF due to temperature inversions

Shack technology

Terms you hear while setting up and while hunting faults.

SWR
standing wave ratio, measure of the match between feed line and antenna
Rückflussdämpfung
how much weaker the reflected wave is, in dB (return loss); 9.5 dB corresponds to SWR 2, 14 dB to SWR 1.5
Smith-Diagramm
circle chart where every impedance has its place: centre = matched, edge = everything reflected, top inductive, bottom capacitive; try it out at /smith
Güte
ratio of reactance to loss resistance of a component or circuit (Q); a coil with 700 Ω and Q 50 has 14 Ω loss, the higher Q, the narrower a tuned circuit
Bode-Diagramm
curve of attenuation (and phase) against frequency, with frequency on a log scale; shows where a filter passes and how steeply it rolls off
Tiefpassfilter
passes everything below the cut-off frequency and attenuates above it; between power amplifier and antenna it keeps the harmonics back, try it out at /filter
Butterworth
filter response with no ripple in the passband, 3 dB down at the cut-off frequency, then 6 dB per octave steeper for each order
Tschebyscheff
filter response with a small, intended ripple in the passband (about 0.1 dB), in return much steeper than Butterworth for the same order
Welligkeit
in a filter, the ups and downs of the passband curve within the band, in dB; 0.1 dB corresponds to an SWR of up to about 1.36
Einfügedämpfung
how much power a filter or component costs in the passband, in dB (insertion loss): losses in coils and capacitors plus mismatch
L-Glied
matching network of two components, one in series and one in parallel; with the coil in series and the capacitor in parallel it is a low-pass filter at the same time
Träger
unmodulated oscillation on one frequency; in the waterfall a thin, even line
Schaltnetzteil
the most common source of interference in the shack: a comb of evenly spaced lines or a broad carpet that disappears when you switch off the power supply
OTH-Radar
over-the-horizon radar on HF, 10 to 40 kHz wide, often with a hard rhythm; also gets into the amateur bands and is reported by the IARU monitoring system
Antennentuner
matches the impedance, but does not turn a poor antenna into a good one
Balun
transition between a balanced antenna and an unbalanced feed line
Unun
transformer between two unbalanced systems, often used with end-fed antennas
Mantelwellensperre
stops current on the outside of the coax shield and with it RF in the house
PEP
peak envelope power, the way the limits are specified
ERP und EIRP
radiated power, relative to a dipole or to an isotropic radiator
dBd und dBi
antenna gain relative to a dipole or an isotropic radiator, difference 2.15 dB
Verkürzungsfaktor
factor between free-space wavelength and physical length; RG58 has 0.66, one metre of it takes 5.05 ns, try it out at /leitung
Wellenwiderstand
ratio of voltage to current of a wave on the line (Z0), depends only on the construction, not on the length; coax is usually 50 or 75 Ω
Reflexionsfaktor
share of the wave that is reflected at a discontinuity: Γ = (Z − Z0) / (Z + Z0); 75 Ω on 50 Ω gives 0.2, open 1, short −1
TDR
time domain reflectometer: sends a steep step into the cable and shows when and how strongly echoes come back, so where the cable ends or is damaged
Stehende Welle
superposition of forward and reflected waves on a mismatched line: peaks and nulls λ/4 apart stand still, their ratio is the SWR
Rauschzahl
how many dB a stage degrades the signal-to-noise ratio with 290 K at the input; a cable with 3 dB loss has a 3 dB noise figure, try it out at /empfangskette
Rauschtemperatur
noise of a stage expressed as the temperature of a resistor at the input: Te = 290 K · (F − 1); a 0.5 dB noise figure is 35 K, 1 dB 75 K, 3 dB 289 K
Friis-Formel
noise of stages in cascade: Te = Te1 + Te2 / G1 + Te3 / (G1 · G2) + …; each stage only counts divided by the gain before it, which is why the preamp belongs at the antenna
Antennentemperatur
noise the antenna brings along, as a temperature: cold sky at 10 GHz a few K, a dish seeing the ground in its side lobes 30 to 60 K, on HF up to millions of K because of band noise
G/T
figure of merit of a receiving system: antenna gain in dBi minus 10 log of the system temperature, in dB/K; more gain and less noise help equally
LNB
low noise block converter at the focus of a dish: amplifies and converts 10 GHz down to an intermediate frequency the cable can handle; for QO-100 usually with a 9750 MHz oscillator
Belegte Bandbreite
range containing 99 % of the transmitted power, half a percent stays outside on each side; for the adjacent channel the width at −40 or −60 dB says more, try it out at /modulation
Tastklick
clicks next to a CW signal because the carrier is switched on and off too hard; with a 5 ms soft edge instead of hard keying the width at −60 dB shrinks from several kilohertz to a few hundred hertz
Splatter
spill-over of an overdriven SSB or AM signal: the power amplifier limits, and mixing products appear next to the channel
Carson-Regel
rule of thumb for FM bandwidth: 2 · (deviation + highest audio frequency); 2.5 kHz deviation and 3 kHz audio give 11 kHz
Modulationsindex
in FM the ratio of deviation to audio frequency (β); at β = 2.405 the carrier vanishes, in AM the modulation depth goes by this name
Intermodulation
mixing products of two strong signals in a stage that is not quite linear; the 3rd order at 2·f1 − f2 and 2·f2 − f1 lands right in the band
IP3
3rd-order intercept point: where the lines of the wanted signal (slope 1) and the 3rd-order products (slope 3) would cross; IM3 = 3 · P − 2 · IIP3, the higher, the better
Dynamikbereich
range between the noise of a receiver and the level at which intermodulation rises out of the noise: 2/3 · (IIP3 − noise)
Superhet
superheterodyne receiver: mixes the signal with an oscillator to a fixed intermediate frequency, where the sharp filters sit
Zwischenfrequenz
fixed frequency after the mixer of a superhet (IF), for example 455 kHz, 9 MHz or 45 MHz
Spiegelfrequenz
second frequency that gives the same IF in a superhet: two IFs away from the wanted signal, on the other side of the oscillator
Vorselektion
filter ahead of the mixer of a superhet that attenuates the image frequency and other spurious responses; after the mixer nothing helps any more
Endfed
wire antenna fed at one end, usually with a transformer
Groundplane
vertical radiator with radials as counterpoise
Yagi
directional antenna with directors and reflector
Magnetic Loop
small, narrowband loop antenna, often for cramped locations
QRP
operating with 5 W at most, often as a challenge in itself
Shack
the radio room
CAT
Computer Aided Transceiver: commands a computer uses to control the radio over USB or the serial port; Yaesu and Kenwood send text such as FA014074000;
CI-V
Icom's CAT: short data frames of bytes with the radio's address (IC-7300: 94h), over USB or a two-wire bus that several radios can share
Speicherkanal
stored frequency with mode, offset, tone and name, called up on the radio with a turn of the knob; you can program it in Rigstudio
Bandstapelregister
Icom remembers the last three settings per band (frequency, mode, filter); the band button jumps to the one used last