Navigation

Click the name of a signal to see more detailed information, possible decoding, and additional sound and waterfall samples

Signal Name	Description	Frequency	Mode	Modulation	Bandwidth	Location	Sample Audio	Waterfall image
'Vario' Airplane Data Controller	This transmitter is found within the UHFUltra High Frequency (300-3000 MHz) FMRS bands, most likely used at airshows to give off barometric pressure, height in altitude represented by a voice, including various tones representing how high/how low the model plane is in the air.	462.61 MHzMegaHertz (MHz) 10^6 Hz — 462.725 MHzMegaHertz (MHz) 10^6 Hz	NFMNarrowband Frequency Modulation		6 kHzKiloHertz (kHz) 10^3 Hz	United States
Accurate positioning by Low Frequencies (ALF)	Accurate positioning by Low Frequencies, a former German DGPS navigation system. No longer in use as of 2013.	123.7 kHzKiloHertz (kHz) 10^3 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	PSKPhase-Shift Keying	2.1 kHzKiloHertz (kHz) 10^3 Hz	Germany
DeltaFix	DeltaFix was a DGPS system that was used to provide precision positioning used in the survey and oceanographic industry.	1.7 MHzMegaHertz (MHz) 10^6 Hz — 3.4 MHzMegaHertz (MHz) 10^6 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	FSKFrequency-Shift Keying	250 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).	Worldwide
Differential Global Positioning System (DGPS)	Differential GPS (DGPS), also known as M823 DGPS and SC-104 DGPS, is a supplementary correction signal used by GPS receivers to increase the accuracy of GPS based positioning.	283.5 kHzKiloHertz (kHz) 10^3 Hz — 2.95 MHzMegaHertz (MHz) 10^6 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	MSKMinimum-Shift Keying (When Shift/Bd = 0.5. It is impossible to get this ratio to be lower than 0.5, hence it is called the 'Minimum' shift.)	150 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). — 250 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).	Worldwide
Eurobalise downlink	Downlink from train to balise. A Eurobalise is a specific variant of a balise, a transponder placed between the rails of a railway.	27.095 MHzMegaHertz (MHz) 10^6 Hz	AMAmplitude Modulation			Europe
Global Positioning System (GPS)	GPS is the USA's global navigation satellite system which provides precision position, navigation, and timing services to devices around the globe.	1,176.45 MHzMegaHertz (MHz) 10^6 Hz — 1,575.42 MHzMegaHertz (MHz) 10^6 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	BPSKBinary Phase-Shift Keying (1 bit per symbol), QAMQuadrature Amplitude Modulation, DSSS, BOC, TMBOC	22 MHzMegaHertz (MHz) 10^6 Hz — 25 MHzMegaHertz (MHz) 10^6 Hz	Worldwide
Ground-Based Augmentation System (GBAS)	GBAS is an advanced aircraft navigation system that provides GPS corrections to aircraft on approach.	108 MHzMegaHertz (MHz) 10^6 Hz — 117.975 MHzMegaHertz (MHz) 10^6 Hz	AMAmplitude Modulation	D8PSK	15 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
HyperFix	HyperFix was a radio-navigation system developed by Racal. Was used by vessels and ships. Has largely been phased out in favor of Differential GPS.	1.6 MHzMegaHertz (MHz) 10^6 Hz — 3.4 MHzMegaHertz (MHz) 10^6 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)		250 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).	Worldwide
Instrument Landing System	Radio navigation system that allows aircraft to perform precision approaches in low visibility conditions.	108 MHzMegaHertz (MHz) 10^6 Hz — 335 MHzMegaHertz (MHz) 10^6 Hz	AMAmplitude Modulation		15 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
John Deere RTK Radio 450	Real-time Kinematic GPS is a satellite navigation technique used to enhance the precision of position data derived from satellite-based positioning systems (global navigation satellite systems, GNSS) such as GPS, BeiDou, GLONASS, Galileo and NavIC.	435 MHzMegaHertz (MHz) 10^6 Hz — 470 MHzMegaHertz (MHz) 10^6 Hz	FMFrequency Modulation	FSKFrequency-Shift Keying	7.49 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
LORAN	LORAN (short for LOng RAnge Navigation) is a hyperbolic radio navigation system.	100 kHzKiloHertz (kHz) 10^3 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	PPMPulse Position Modulation	20 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
Non-Directional Beacon (NDB)	A Non-Directional Beacon (NDB) is a ground-based, low frequency radio transmitter used as an instrument approach for airports and offshore platforms.	190 kHzKiloHertz (kHz) 10^3 Hz — 1.8 MHzMegaHertz (MHz) 10^6 Hz	CWContinuous Wave	A2A (AMAmplitude Modulation)	2 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
Primary Aeronautical Surveillance Radar	A Primary radar (PSR Primary Surveillance Radar) is a conventional radar sensor that illuminates a large portion of space with an electromagnetic wave and receives back the reflected waves from targets within that space.	1,215 MHzMegaHertz (MHz) 10^6 Hz — 1,400 MHzMegaHertz (MHz) 10^6 Hz	RAW	Pulse	3 MHzMegaHertz (MHz) 10^6 Hz	Worldwide
Radioteknicheskaya Systema Dalney Navigatsii (RSDN-20)	RSDN-20, also known as Alpha, is a Russian hyperbolic radio navigation system. Presumed to be used for Russian ships, submarines and aircraft in the northern hemisphere, possibly worldwide.	11.91 kHzKiloHertz (kHz) 10^3 Hz — 14.88 kHzKiloHertz (kHz) 10^3 Hz	CWContinuous Wave		20 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).	Russia
Secondary surveillance radar (SSR)	Secondary surveillance radar (SSR)is a radar system used in air traffic control. A surveillance radar system which uses transmitters/receivers (interrogators) and transponders.	1,030 MHzMegaHertz (MHz) 10^6 Hz	RAW	PPMPulse Position Modulation	3 MHzMegaHertz (MHz) 10^6 Hz	Worldwide
Sonne	Sonne (Called Consol by the Britons) was a low-frequency radio range based radio navigation system used for long range navigation.	250 kHzKiloHertz (kHz) 10^3 Hz — 350 kHzKiloHertz (kHz) 10^3 Hz	USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)	OOKOn-Off Keying Modulation	1 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).	Worldwide
Tactical Air Navigation System (TACAN)	Radio navigation technology that measures the slant range (distance) between an aircraft and a ground station by timing the propagation delay of radio signals.	960 MHzMegaHertz (MHz) 10^6 Hz — 1,213 MHzMegaHertz (MHz) 10^6 Hz				Worldwide
Transit 5B-5	Transit 5B-5, a former TRANSIT navigation satellite, is the oldest satellite known to still transmit a signal. Considered "dead" because its navigational systems failed after 19 days of operation, it still emits a telemetry signal when illuminated.	136.658 MHzMegaHertz (MHz) 10^6 Hz	WFMWideband Frequency Modulation	PCM, PAMPulse Amplitude Modulation, FMFrequency Modulation, PM	32 kHzKiloHertz (kHz) 10^3 Hz	Worldwide
VHF Omnidirectional Range (VOR)	A type of radio navigation system used by aircraft. It is distinctive in that the center frequency is flanked by two FMFrequency Modulation waves.	108 MHzMegaHertz (MHz) 10^6 Hz — 117.95 MHzMegaHertz (MHz) 10^6 Hz	NFMNarrowband Frequency Modulation	AMAmplitude Modulation, FMFrequency Modulation	21 kHzKiloHertz (kHz) 10^3 Hz	Worldwide