SigIntel

'Ghadir', is an Iranian over the horizon radar, part of Iran's Sepehr Phased Radar System.

OTH-SW is a Chinese over-the-horizon radar. It is known to operate with pulse repetition frequencies of 43 Hz and 86 Hz.

This transmitter is found within the UHF FMRS bands, most likely used at airshows to give off barometric pressure, height in altitude represented by a voice, including various …

Unknown military-use signal reminiscent of SECURENET CVSD voice.

Nordic Mobile Telephone (NMT, NMT-450, and NMT-900) is a first generation analog cell phone system. Originally designed for and by Nordic countries (Finland, Sweden, Norway, Den…

The first generation of cellular mobile telecommunications, which used analogue NFM voice.

Original remote of KIA Carnival (2006).

29B6, nicknamed 'Контейнер' (Kontayner), is a Russian over the horizon radar. It is currently very active in Europe. The radar uses 150 antenna masts with data transmission syst…

GSM (Global System for Mobile Communications) is a standard developed by ETSI to describe the protocols for second-generation (2G) digital cellular networks used by mobile phone…

CDMA-One also known as IS-95, was the first ever cellular standard technology based on Code Division Multiple Access (CDMA). It is a predecessor of the 1xRTT (CDMA2000/IS-2000) …

WCDMA, known primarily as 3G mobile, is a family of 3G data protocols used to send voice, text and signaling data to smart phones and other wireless devices.

The sound of an RC controller signal from an old amphibious toy car

Acquired via telecommunications carrier hardware during interference investigation of an Australian cellular network.

NOTE: PLEASE TYPE A LONGER DESCRIPTION HERE IF NEEDED OTHERWISE JUST DELETE. IF THERE IS NOTHING TO ADD OR YOU DON'T REQUIRE ALL SECTIONS, JUST DELETE THE TEXT.

Long Term Evolution Network. Also known as 4G LTE Data and Evolved Universal Terrestrial Radio Access (E-UTRA). Data service for wireless consumer devices.

LTE 450 refers to the deployment of Long-Term Evolution (LTE) technology in the 380-512 MHz frequency band. LTE 450 networks allow various 4G LTE options to deliver efficient an…

5G cellular, also known by 3GPP '5G' NR (new radio), etc. is a newly released cellular standard that allows for backwards compatibility with 4G LTE, and will allow for several …

5G cellular, also known by 3GPP '5G' NR (new radio), etc. is a newly released cellular standard that allows for backwards compatibility with 4G LTE, and will allow for several …

A technology originally introduced in LTE (eMBMS) that enables efficient transmission of the same content to a large number of users at once — that is, broadcast or multicast in…

Voronezh (Воронеж) is a Russian radar family capable of aircraft and ballistic missile monitoring.

HaLow (802.11ah) is a wireless technology standard for exchanging data between devices over medium distances. Released by the Wi-Fi Alliance in 2016, it was initially developed …

IEEE 802.11ax-2021, also known as Wi-Fi 6, is a WLAN standard improves upon previous Wi-Fi standards by utilizing 1024QAM modulation, larger channel bandwidths, and improved eff…

IEEE 802.11n-2009, commonly shortened to 802.11n, is a wireless-networking standard that uses multiple antennas to increase data rates. The Wi-Fi Alliance has also retroactively…

8PSK modulation is a way to encode data using eight phase angles. Each symbol can encode three bits of data. It can achieve higher data rates than other phase modulation schemes…

Unidentified pulsating signal residing on 1915 KHz as received in Northeast (East Central NY state). Bandwidth is approximately 30KHz wide. Signal levels S5 to S9.

Accurate positioning by Low Frequencies, a former German DGPS navigation system. No longer in use as of 2013.

Used for some PC monitors to keep the monitor's power on (or sleeping) across the spectra. Monitors may transmit whatever frequency peaks needed to keep it "on" or on sleep mode.

AHICDM is a simple, slow and reliable modulation protocol that allows binary data in standard ASCII to be sent over audio.

AHSC uses a randomly generated One-Time-Pad to secure communications between transmitter and receiver. Used for unscheduled transferring of data due to the architecture of the p…

A variant of POCSAG/FLEX with audio FSK modulation based off of the bell 202 tones. Typically found as uplinks/downlinks to pager network transmitters.

ACARS is a digital datalink system for the transmission of short messages between aircraft and ground stations via airband radio or satellite.

Aist 2D is a Russian microsatellite developed and designed by a group of Samara Aerospace University students, postgraduates, and scientists in cooperation with TsSKB-Progress.

Akkord-SS-PD (АККОРД-СС-ПД), also known as “Akkord-165” is a Russian datalink used during the invasion of Ukraine. Akkord is a rather old family of datalink protocols, Akkord-16…

ALE-400 is an amateur version of the 2G ALE standard. It is adapted to the demands of amateur radio emergency traffic handling.

This is the complete list of all identified signals in our Signal Identification Guide ordered in alphabetical order. There are currently 589 identified signals in our database.

Alps Electric Co. TWB1U840 Key Fob for Nissan Sentra, Nissan Versa, and Nissan Leaf model years 2013-2017+.

The initial generation of cellular mobile radiotelecommunications, similar to trunked radio. -- (Audio Sample is *loud* ) --

Long range commercial broadcast and international radio. Also used for aviation communications.

Amplitude Modulation Signalling System (AMSS) is a DRM-based radiotext and data technology for AM broadcasting, like RDS that is used for FM. It transmits as a subcarrier, phase…

AMSAT-P3D (Known as Phase 3D, OSCAR-40, and AO-40) is a amateur radio satellite built by AMSAT. As of 2004, the satellite's systems have failed.

Data downlink from Aprizesat microsatellites. Aprizesat constellation consists of 12 Active satellites, These provide a worldwide M2M asset tracking service and relay AIS packets.

A direct broadcast sent in the X band by the NASA Aqua satellite for reception by end users.

Some polar weather satellites from the METOP and POES series carry ARGOS A-DCS (Advanced Data Collection System), which is a system to collect data from sondes and other remote …

ARQ-E, also known as ARQ-1000 Duplex or ARQ-1000D, is a synchronous full-duplex ARQ system. ARQ-E3 is a variant that uses a different alphabet encoding. Mainly used by French Mi…

ARQ-M2-242 (Also known as TDM 242, TDM-2, 96-TDM, and ARQ-28) is a two-channel time division multiplexed telex system. This is the CCIR 242 standard version. Used in Aeronautica…

ARQ-M2-342 (Also known as TDM 342, TDM-2, 96-TDM, and ARQ-28) is a two-channel time division multiplexed telex system. This is the CCIR 342 standard version. Used in Aeronautica…

ARQ-M4-242 (Also known as TDM 242, TDM-4, 192-TDM, and ARQ-56) is a four-channel time division multiplexed telex system. This is the CCIR 242 standard version. Used in Aeronauti…

ARQ-M4-342 (Also known as TDM 342, TDM-4, 192-TDM, and ARQ-56) is a four-channel time division multiplexed telex system. This is the CCIR 342 standard version. Used in Aeronauti…

ARQ-N is a synchronous dual channel ARQ mode identical to ARQ-E, with the only difference being that ARQ-N has no symbol inversions. Formerly used by Italian Diplomatic services.

ARQ6-90, also known as ARQ-6-90 and ARQ-6/90, is a 6-character block simplex ARQ system formerly used by French and Italian diplomatic services exchange of teletype-data. It is…

ARQ6-98, also known as ARQ-6-98 and ARQ-6/98, is a 6-character block simplex ARQ system formerly used by French and Italian diplomatic services for the exchange of teletype-data…

ASCII (also known as ITA5 or IRA) is an amateur radio telegraphy signal using the ITA-5 alphabet.

The Advanced Television Systems Committee (ATSC) 3.0 standard (marketed as NextGen TV) is a revised set of video broadcasting specifications that outlines improvements to spectr…

Advanced Television Systems Committee Television. 8VSB Modulation

Audi keyfobs transmit encrypted, short radio bursts that carry authentication data to the vehicle. These bursts trigger actions such as unlocking doors, opening the trunk, or en…

This is an example of the Autocab Media Data Terminals used by cab companies all over the world.

Automated Train Control System (ATCS), specifically ATCS Spec. 200, is a standardized communication system for railroads designed to ensure safety by monitoring locations of tra…

ADS-B is used by aircraft as an alternative to secondary radar. It broadcasts GPS position (latitude, longitude), pressure altitude, callsign, as well as track and ground speed.

Automatic Identification System (AIS) is used by ships to broadcast position and vessel information.

Automatic Link Establishment, 2G ALE (Official designation MIL-STD-188-141A and/or MIL-STD-188-141B (Appendix A)) is the current standardized method of establishing connections …

3G ALE (ARCS) is the next generation of ALE (Designated by MIL-STD-188-141B (Appendix C)). Also known as STANAG 4538, although MIL 188-141 does not provide Fast LSU.

Automatic Link Set-up (ALIS) is an automatic link system used by Rohde & Schwarz modems.

Packet system for real time data communications. Used by hams for location reporting, weather stations etc.

Automatic Picture Transmission (APT), also known as NOAA-GEOSAT, was an analog image transmission mode used by the NOAA weather satellites and some Russian weather satellites to…

ATIS systems are identification tags used by inland commercial waterway traffic on rivers in Europe. The FSK burst is appended at the end of every voice transmission by the vess…

AUTOSPEC is a synchronous FEC teletype system used by British coastal stations to communicate with North Sea oil rigs. Also known as Autospec-bauer, Bauer, and Autospec Mk1. Thi…

B-Netz, was an analog, commercial mobile radio telephone network that was operated by the Deutsche Bundespost in Germany (at first only West Germany) from 1972 until 1994. The s…

BalDR weather sensor SCADA telemetry, A signal standard that belongs to the BalDR brand of weather sensors, and might also belong to other brands of weather sensors that use the…

Proprietary GMSK mode used for voice by Fujian Baofeng walkie talkies

Beta is the designation of a time signal service which is transmitted from multiple Russian VLF stations.

BIIS (also known as BIIS 1200) is an ETSI protocol for a digital selective calling method with the added benefit of extended capability of transmitting data that exceeds what co…

Bluetooth is a wireless technology standard for exchanging data over short distances from fixed and mobile devices and building personal area networks (PANs). Invented by teleco…

"Bluetooth Smart Ready" means the device can be used with Classic or Low Energy

Wideband telemetry signal from BlueWalker-3 experimental satellite.

This coded signal was sent by BMW Car-Key. It is used to open and lock bimmer doors.

BPC is the callsign of the Chinese low-frequency time broadcasting station, located near Shangqiu, Henan in China.

BPM is a time signal transmitted by the Chinese Academy of Sciences, broadcasting from CAS's National Time Service Center in Pucheng County, China.

BR-6028 is a VFT (Voice Frequency Telegraph) frequency and time diversity modem using 7 data channels. It is sometimes also known as BARRIE, USA-7, or 6028.

BRAS-3 and the closely related RS-10 are Russian medium frequency hyperbolic navigation systems used for marine navigation

Proprietary satellite network owned and operated by Inmarsat that provides cellular 3G equivalent data and voice services to subscribers.

Canadian Meteor Orbit Radar, or CMOR, is a meteor detection radar located near Tavistock, Ontario.

CAS-4A/B Satellite 4.8 kbps GMSK Telemetry Downlink.

CBET "Critical Band Encoded Tones" are tones added into radio broadcast's audio output for identification purposes.

CCIR 493-4 Selcall, also known as HF Selcall, Australian Selcall, and Codan 8580 Selcall, is a Selcall standard developed in Australia for the HF band. Used by Amateur radio and…

CCIR selcall consists of CCIR-1, CCIR-2, and PCCIR, which are 5-tone selcall modes for VHF/UHF radios. CCIR-1 and CCIR-2 only differ in the tone duration, and PCCIR only differs…

CCITT is a 5-tone selcall system for VHF/UHF radios.

CDMA2000, or IS-2000, is a cellular network standard utilizing the CDMA technology for calls and data.

2G: GSM - D-AMPS - 2G CDMA (IS-95) 3G: CDMA2000 - UMTS - CDMA420 4G: LTE Downlink - LTE Uplink - LTE420 MCX

Naval VHF time signal found in Chilean Coast, in Vina Del Mar

Convergent Digital Radio (CDR) or China Digital Radio is an in-band-on-channel (IBOC) digital radio broadcasting format used in China. It can be found in multiple bandwidth conf…

A Chinese over the horizon radar, known as "foghorn" among amateur radio operators. Not much is known about it.

Chinese OTH radar with wide bandwidth and usually low sweep rate. Little information is available.

A 30-tone OFDM data mode, probably used by Chinese military or other agencies.

Chinese 4+4, also known as 4+4 or PRC 4+4, is a multi-carrier transmission mode. It used by Chinese Diplomatic services with most traffic originating from Beijing, China.

Commercial AM Broadcast jamming signal that plays Chinese folk songs to jam specific radio stations in Asia from being received by listeners.

Chinese radio jamming signals intended to disrupt/censor broadcast communications.

Chinese Modem MFSK-64

Chinese radios failing to mimic mdc1200 or produces really old mdc1200 sound.

CHIP is a spread-spectrum PSK mode developed by Antonino Porcino IZ8BLY. CHIP-64 runs at 37.5 bps, whereas CHIP-128 runs at 21.09 bps.

CHU is a time signal radio station operated by the Institute for National Measurement Standards of the National Research Council of Canada.

Three CIS-14 signals overlaid on top of each other in a 3100 Hz VFT bandwidth, operating at 100 bd

Three 144 Bd FSK signals in a 3100 Hz VFT bandwidth. Reportedly phased out.

Three 50 bd Baudot signals in a 3100 Hz VFT bandwidth.

CIS FTM-4 is the unofficial designation of a four-tone MFSK data mode which is apparently used by Russian military.

This MSFK-11 signal is widely believed to originate from Russia, used by Russian intelligence, military or diplomatic agencies.

Enigma Designation XPA2, also known as MFSK-16, CIS MFSK-14, and CIS MFSK-16, is a 14-tone MFSK signal said to have origin from Russian Intelligence and Foreign Ministry stations.

Enigma designation XPB is a custom 16-tone MFSK mode said to have origin from Russian Intelligence and Foreign Ministry stations.

Enigma Designation XPA, also known as MFSK-20, CIS MFSK-17, and CIS MFSK-20, is a 17-tone MFSK signal said to have origin from Russian Intelligence and Foreign Ministry stations.

An MFSK data mode that is believed to originate from Russian sources. Changes between MFSK-21, MFSK-13 and different speeds.

New Russian MFSK Modem that uses 68 MFSK (5 tones at a time) as well as a 9000 Bd 8-PSK insert every second which spans 10 kHz wide. This signal is often found attributed with C…

Russian OFDM HDR (High Data Rate) Modem. Has three main modes: CIS-45, CIS-60, and CIS-93, corresponding to the number of OFDM tones in the signal.

CIS OFDM-121 is an OFDM mode that uses OFDM bursts with 121 channels, spaced by two QPSK-like bursts. Not all of the 121 available channels of OFDM bursts are used and it's poss…

Presumably Russian MFSK signal with wide bandwidth and 17 tones

CIS-11 (Also known as TORG-11) is a radio duplex teleprinter system used by Russian meteorological stations

CIS-112 OFDM signal. Has a preamble of 7 Tones (not including carrier), then 56 tones before entering into the 112 tone data transmission.

CIS-12 (Also known as MS5, FIRE, AT-3004D, AT-3104D, T-230) is a 12-tone PSK Russian military multi-channel modem.

CIS-1200, Mahovik, "Flywheel" in Russian, is a PSK based mode that can transmit both voice and data. It is transmitted from a Russian T-230-1A.

CIS-128 is an OFDM mode that uses 128 channels, with one “off” channel in the center, so the signal is divided into two 64 channel parts.

CIS-1280 is a OQPSK (Offset Quadrature Phase Shift-Keying) modulation data modem signal. Also known as Soviet Mil(MOD)/FAPSI/PTT system. These stations are recognizable in that…

Also known as AMOR and AMOR96. Synchronous FSK duplex teleprinter system with ARQ.

CIS-16 is a BPSK 16-tone mode, possibly transmitted from a modified AT-3004D or AT-3104 type Russian military transceiver. Also known as CIS 16x75 Bd for the 75 bd speed in each…

Russian AT-3104 Modem signal, 20-tone OFDM DQPSK signal. Has characteristic pilot tone located 3300 Hz from suppressed carrier. All 20 channels operate at 75 Bd.

Known as CIS-300 Burst, FSK mode used with 300 Bd rate with a starting and ending tone on the upper part of the signal.

CIS-3000 is an 8-PSK Data Modem protocol. Its source is traced to Russia. 3000 is for its 3000 Baud speed (maximum speed is technically 9000 bps).

CIS-36-50, also known as BEE-36, is an FSK modem used by the Russian Navy.

CIS-40.5 (Also known as T-206) is an FSK signal used in Russian Military Communications Equipment. Used as a telegraph channel, encrypted.

CIS-48 is an interesting data mode with a unique format. It uses a 4 DBPSK Preamble with a constant tone and changing OFDM modes as it transmits data. Origin is suspected to be …

CIS-50-50 is very similar to CIS-36-50. The main difference is in the available baud rates and frequency shifts used.

CIS-8181 is an FSK modem used by the Russian navy.

Dump to European ground station from the CLOUDSAT cloud profiling satellite. CLOUDSAT has a CPR (Cloud Profiling Radar) that operates at 94 GHz to create a vertical sounding (cr…

CLOVER 2000 is an upgrade to CLOVER-II, a digital data protocol developed by Ray Petit and HAL Communications. Sometimes referred to as XCLOVER or 8 Tone CLOVER.

CLOVER 2500 is a new upgrade to CLOVER-2000, adding 25% more speed to the CLOVER system.

CLOVER-I was the first iteration of the Clover series of digital modes. Was never released for commercial use, replaced by CLOVER-II. Also known as Cloverleaf.

CLOVER-II is the advancement of CLOVER-I, with 4 tone pulses and a max data rate of 750 bps. Also known as Q-CLOVER and QUAD-CLOVER.

The AN/FPS-108 COBRA DANE is a PESA phased array radar installation operated by Raytheon for the United States Space Force (originally for the United States Air Force) at Eareck…

Codan Data Modulation for Codan Data Modems. Has 3 distinct signals: Data, ALE, and SELCAL. This modulation is used in Codan's 9001, 9002, 3012 and 3212 modems.

CODAR (Coastal Ocean Dynamics Applications Radar) is used for near-surface ocean monitoring, such as waves and water current.

COFDMTV is an easy-to-use picture transmission mode based on Coded Orthogonal Frequency-Division Multiplexing (COFDM).

Coherent BPSK, also known as C-BPSK, was an experimental amateur mode developed by Bill DeCarle VE2IQ.

Coherent CW (also known as CCW) was a strictly timed morse code mode designed by Ray Petit W7GHM (The same inventor of CLOVER). CCW depended on accurate timing from both receive…

Low speed FSK telemetry to monitor and control warning sirens that are used to warn the public of threats such as tsunamis, severe weather, chemical spills and civil emergencies.

Contestia, developed by Nick Fedoseev (UT2UZ) in 2005, is a digital mode derived from Olivia. It aims to deliver a compromise of speed and performance.

CTCSS, also known as Private Line and Channel Guard, is a low continuous tone transmitted on NFM voice transmissions that is used to squelch and manage transmissions on a given …

"Speed control by beacons" railway safety system used in France and the Channel Tunnel line in the UK.

Coquelet is an MFSK system, similar to Piccolo. Also known as COQ-8, COQ-12, and COQUELET 8 V 2. Uses ITA-2 charset. It's two main modes are Coquelet-8 and Coquelet-13. No longe…

Direct Broadcast digital signal from the CORIOLIS satellite, primarily carries data from the WindSat instrument.

CRY2001 is a voice scrambling mode used on Sailor CRY2001 Scramblers. Fisherman often use these modes to communicate with privacy.

Cuban jammers jam the frequencies of Radio Martí, Radio Republica and occasionally WRMI radio.

CV-786 is a wideband FSK mode built in Rockwell-Collins MDM-2001 modems. Also known as TRC-75, as it was used in TRC-75 transceivers. A military-based Radio TeleTYpe mode.

D-STAR is a digital voice protocol used by ham radio. Is sometimes routed over the internet for international communications.

Datawell Buoy HF Links transmitted by Datawell Marine measurement buoys, measuring ocean conditions, temperature, and wave current.

The is a research beacon for training neural networks.

DCF77 is a German longwave time signal radio station based at 77.5 kHz. DCF uses an AM modulated carrier and phase modulation sidebands to transmit its time signal.

Delfi-C3 Telemetry was a telemetry signal sent from the Delfi-C3 university-class satellite.

DeltaFix was a DGPS system that was used to provide precision positioning used in the survey and oceanographic industry.

Denso Wireless Key Fob 4EA built by Denso Corporation for General Motors auto brands Chevrolet and Buick. Used on Chevrolet Camaro and Malibu from 2016+. Used on Buick Lacrosse …

GRAW DFM-09 radiosonde measures temperature, humidity, air pressure, wind direction, and wind speed.

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.

Digisondes are ionosondes that use pulsed signal that can gather more radar information than a traditional ionosonde sweep.

DAB is an audio broadcasting standard containing a multiplex of digital radio stations in the signal.

DAB+ is a medium of delivering broadcast radio, containing multiple stations in a single multiplex.

Digital Dispatch Systems Mobile Data Terminal is a dispatching system used by taxi and private transportation companies.

DECT is a ETSI standard for short range communications, mainly cordless phones. It uses a 10 channel/24 slots in a TDMA FDD structure. Audio sample is 100 times slower than real…

Digital Mobile Radio (DMR) is an open digital mobile radio standard defined by ETSI and used in commercial products around the world. Mostly used by private network and local po…

Digital Multimedia Broadcasting (DMB) is a digital radio transmission technology developed in South Korea as part of the national IT project for sending multimedia such as TV, r…

Method for transmitting digital images via radio, similar to WinDRM or KG-STV

dPMR is an open, non-proprietary trunked radio standard developed by ETSI, published under ETSI TS 102 658. Supports both data and digital voice transmission.

Digital Radio Mondiale (DRM) is a digital commercial broadcasting mode used to deliver FM-comparable sound quality to shortwave radio.

DRM+ is a VHF implementation of DRM primarily for the FM broadcast band.

DVB‑C is a cable‑based digital TV transmission standard that delivers MPEG transport streams over coaxial networks using QAM modulation. It was first published as ETSI EN 300 42…

DVB‑S and DVB‑S2 are both satellite broadcasting standards, but DVB‑S2 is a more advanced and efficient evolution of the original system.

Digital Video Broadcasting — Terrestrial (DVB-T) is a digital broadcast television format used in Europe and in many other countries in the world.

Digital in-band signalling used to squelch and manage transmissions on a given frequency.

DisplayPort is a digital standard used to carry video and audio data to computer monitors. It emits RF interference in the 300-400 MHz range when in use.

Analog Distress Radiobeacons are simple siren-based transmitters that were installed in older EPIRB's, PLB's and ELT's. Currently used as a supplementary homing signal in modern…

Digital Distress Radiobeacons (EPIRB's, PLB's and ELT's) are emergency radio beacons used for search and rescue operations to locate a vessel, plane, or person in distress.

Distributed power refers to the placing of an extra locomotive at an intermediate point in the middle section of a train. This locomotive unit is remotely controlled from the l…

DominoEX, also known as just Domino, is an IFK (Incremental Frequency Keying) mode developed by Murray Greenman ZL1BPU and Con Wassilieff ZL2AFP in 2004 that was the first fully…

DominoF was the first experimental implementation of the Domino family of IFK modes, developed by Con ZL2AFP. DominoF used dual interleaved tone sets. Superseded by DominoEX.

Driftnet Radio Buoys are extensively used by fishing boats operating in open seas and oceans for collecting long fishing lines or fishing nets, with the assistance of a radio di…

DTMF is a signaling mode used for a variety of purposes. It's most known for telephony dialing, but is in use for many different applications such as DTMF paging for DTMF-enable…

Duga (Russian: Дуга́) Soviet over-the-horizon radar, now defunct

DUP-ARQ, also known as ARTRAC and 125-ARTRAC, is a semi-duplex ARQ system once used by Thai and Hungarian Diplomatic services.

DUP-ARQ-2 (also known as ARTRAC II) is a further development of the DUP-ARQ system and the system characteristics are very similar. DUP-ARQ-2 allows transmission of ITA-2 (Baudo…

DUP-FEC-2 is a further development of the DUP-ARQ system and the system characteristics are very similar. Uses FEC instead of ARQ and runs at either 125 bd or 250 bd.

Seen it on the Web-SDR Twente. It could be on any frequency. It's quite a short signal to contain a picture. Text (a callsign?) is visible in the waterfall sometimes at the en…

The EBRO keyfob is a compact wireless remote used for vehicle access and basic control functions. It features a simple, ergonomic design with clearly defined buttons for locking…

ECG Telemetry from a pacemaker.

EEA is a 5-tone selcall mode defined by the Electronic Engineering Association in the United Kingdom.

Europäische Funk-Rundsteuerung (EFR) Teleswitch (European Radio Ripple Control GmbH (ERA) Teleswitch) is an energy management system operated via long-wave radio. Uses two trans…

EIA is a 5/6-tone selcall mode defined by the Electronics Industries Association in the United States. Also known as Motorola MetroPage.

This signal comes from an RF remote control device that transmits in UHF over 433.92MHz and controls the arming and disarming system of an electric fence.

Electrical substation SCADA protocol used by EDF (Électricité de France).

Broadcasts the data from the GGAK-E cosmic ray detector onboard ELEKTRO-L geostationary weather satellites

The Emergency Alert System (EAS) is a national warning system in the United States, implemented since 1997, superceding the Emergency Broadcast System (EBS).

The Emergency Managers Weather Information Network (EMWIN) is a system for distributing a live stream of weather information in the United States. This is the VHF Repeater of th…

Transmits train telemetry such as brake status and accidental separation information to the head locomotive.

EDACS is a trunked radio system developed by General Electric and Ericsson. EDACS was invented by General Electric in the mid-80s and is currently owned by Harris Corporation. H…

Ethernet Over Powerline, is an alternative way to reach ethernet cables through a set of adapters that go into outlets that can be plugged directly in the router instead of rout…

EURO is a 6/7-tone selcall mode used in VHF/UHF radios. Also known as EuroSignal.

Downlink from train to balise. A Eurobalise is a specific variant of a balise, a transponder placed between the rails of a railway.

European Radio Message System (ERMES) is a European common standard for paging developed by the European Telecommunications Standards Institute (ESTI)

Enigma designation F03 is a family of digital FSK modes, used by the "Polish 11" numbers station operator, which is likely a Polish intelligence agency.

F07 is a Russian digital number station known for using multiple modulation types, including MFSK, BPSK and FSK.

FEC-A, also known as FEC-100 or FEC-100A, is a synchronous simplex ARQ system that uses the ITA 2 alphabet. This mode was once used by many embassies, diplomatic services, and n…

Signalling protocol developed for Federal Signal's various warning and mass notification appliances. This signal is used for activation and telemetry of all units in a network.

Fast Low-latency Access with Seamless Handoff Orthogonal Frequency Division Multiplexing (FLASH-OFDM) is a mobile data access technology developed by Flarion.

FLEX (Flexible Wide Area Paging Protocol) is Motorola's high speed one-way paging protocol that supports 1600, 3200, and 6400 bps. FLEX can transmit tone, numeric, alphanumeric,…

Commercial Broadcast FM radio stations. Used for the broadcast of many different radio programs, including music, news, sports, weather, and talk shows.

FM NBTV is a method to send moving images in a very narrow bandwidth (maximum 3 KHz)

FreeDV Coherent PSK (Also known as FreeDV 700) is a robust Digital Voice mode developed by David Rowe for his FreeDV Digital Voice Software.

FreeDV plus Video (also known as FreeDV+) combines analog FM multicarrier Narrow Band TV (NBTV) by Con Wassilieff, ZL2AFP, and FreeDV digital voice by David Rowe, VK5DGR.

Frequency Division Multiplex Digital Voice (FDMDV), also known as FDMDV 14+1-tone, is a digital voice mode originally developed by Peter Martinez G3PLX and Francesca Lanza HB9TL…

FSK441 is a high speed meteor scatter communication mode. FSK441 uses a baud rate of 441 Bd.

Fast Simple QSO (FSQ) is an amateur radio digital modulation mode developed by Con Wassilieff ZL2AFP with Murray Greenman ZL1BPU in 2015.

FST4 is a 4-GFSK amateur radio communications mode, designed especially for making contacts (QSO's) on LF and MF frequency ranges under extreme weak-signal conditions. It is par…

FST4W is an amateur radio digital protocol designed particularly for the LF and MF bands, for quasi-beacon transmissions of WSPR-style messages. FST4W uses 4-GFSK modulation and…

FT4 is an amateur radio contesting communication protocol developed by Joe Taylor (K1JT) and Steve Franke (K9AN) descended from FT8.

FT8 is an extremely-weak-signal amateur radio mode that transmits very limited communications. JS8, a variant of FT8, can send full conversations and relay messages

FUNcube-1 Telemetry is a telemetry signal sent from the Funcube-1 Cubesat amateur radio satellite.

72-75 MHz transmitters are used to control various types of RC models. RC Controllers that use 72-75 MHz don't seem to be used as often as they used to.

Golay-Teleprinting Over Radio (G-TOR) is an FSK proprietary standard developed by Kantronics Inc. and is used by radio amateurs, military (Irish Air Corps/Navy, Mexican army) an…

Gandalf MDT was developed by Gandalf Mobile Systems, a subsidiary of Canadian company Gandalf Technologies. Used primarily by taxi and courier services in Canada and the United …

LRIT (Low-Rate Image Transmission) is used to transmit images on the GK-2A satellite

Glenayre's Paging Link. With QAM being used, It is a way to upkeep a linked paging transmitter when no data is broadcast. Glenayre C2100/C2000 model control systems were likely…

Globe Wireless' Maritime Digital Radio was a system of 24 stations around the globe offering data services to large cargo vessels. Since 2014, GW has discontinued their HF network.

This is the proprietary HF Data Signal Protocol for the Rohde & Schwarz HF Modem GM2100.

Global Maritime Distress and Safety System's Digital Selective Calling (GMDSS-DSC) is a maritime communication protocol intended to initiate ship-to-ship, ship-to-shore and shor…

Telemetry signal sent from GOES 16, 17 and 18. GOES is a family of Geostationary Operational Environmental Satellite operated by the United States National Oceanic and Atmospher…

Comes from the geostationary satellites GOES 16 and GOES 17. Relays information about water levels, lightning strikes, and other information.

GOES HRIT is a retransmission of satellite imagery and other information from the GOES-R series of satellites.

GOES Rebroadcast (GRB) is a form of data sent from the GOES-R series of satellites that contain information from all of the instruments on board the GOES satellites

Golay Paging (or Golay Sequential Code, GSC) is a one-way 2-FSK paging format developed by Motorola. It is capable of transmitting tone, numeric, alphanumeric, and voice pages.

Gonets (Russian Гонец, for Messenger) is a Russian civilian low Earth orbit communications satellite system.

1.925hz pulsing signal (5 pulses) that repeats every few seconds around 5-10 times, then stops for an unknown period. Strong enough to completely disrupt AGC on CB band. Signal …

The Grand Réseau Adapté à la Veille Spatiale (GRAVES) system is a French space-surveillance system for low-orbit (up to 1000km) satellites. Emitter is based near Dijon, France.

The DFM-06 is a standard radiosonde for most applications. It is perfectly suited for synoptic observations or military applications.

GRAW DFM-09 performs measurement of temperature, humidity, air pressure, wind direction and wind speed.

Radiosonde developed by Graw/Noris Group GmbH for upper air weather observation

SAQ stands as the sole transmitter reliant on an alternating current generator. Recognized as a UNESCO World Heritage site, it employs the last operational Alexanderson alternat…

GBAS is an advanced aircraft navigation system that provides GPS corrections to aircraft on approach.

Transmitting site owned by the Ministry of Defense. Originally constructed in 1946 and was originally used as a shortwave radio station. In present time, the transmitting site i…

HC-265 is a Voice Scrambling mode developed by Hagelin Crypto for their HC-265 CRYPTOCOM secure voice unit.

Haegelin Crypto ARQ (HC-ARQ) was an FSK synchronous simplex ARQ system used by the UN and International Rescue Committee. This mode has been phased out and is no longer in use.

HD Radio is a proprietary digital broadcast radio format transmitted in North America, usually as sidebands on analog carriers. This is the AM band implementation of HD Radio.

HD Radio is a proprietary digital broadcast radio format transmitted in North America, usually as sidebands on analog carriers. This is the FM band implementation of HD Radio.

HDMI is a popular media source for delivering video, audio, all in the same stream. Unfortunately, there is massive interference from it when a neighboring SDR is near it. It …

Hellschreiber (Also known as Feld Hell or just Hell) is a teleprinter system developed in the late 1920's by Rudolf Hell, a German inventor.

A HF trading link in idle state which strongly resembles an FMCW radar with 120 Hz sweep rate. Has been observed to transmit CW ID once per hour.

HFGCS is a series of networks deployed by the United States Air Force to send encoded messages to deployed aircraft. This network is well known for it's coded EAM's (Emergency A…

HAARP is a ionospheric research program conducted in Gakona, Alaska.

HFDVL (or HFD+VL) is an experimental mode developed by research groups from The University of Las Palmas de Gran Canaria and The Polytechnic University of Madrid. This mode is i…

HFDL, also known as HF-ACARS, ARINC 753, ARINC 635, and HF DATALINK,is a data link that aircraft use to communicate short messages over long distances using HF signals.

The HIPAS (HIgh Power Auroral Stimulation) Observatory was a research facility, built to study the ionosphere and its influence on radio communications. It was located 25 miles …

The HRD direct broadcast is an X-band continuous downlink from NOAA JPSS satellites of mission environmental data to users on the ground that are equipped with a suitable receiver.

High Speed USB 2.0 clock noise. Shows up at multiples of 480 MHz.

HNG-FEC was a full duplex system developed and used solely by the Ministry of Foreign Affairs in Hungary. Used 100.05 bd with 500 Hz shift FSK. This mode is no longer used today.

Proprietary FFSK data network used for public transport telemetry. It is primarily used to track and control vehicles, and facilitates PTT-ID for communication with tram drivers.

An efficient RTTY-like 4FSK mode that transmits binary data, used for amateur high altitude balloon telemetry. Developed by the Project Horus group.

Telemetry signal sent from the HORYU-4 university-class satellite Launched by Kyushu Institute of Technology in Japan

RF Interference Signals From HP Laptop

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.

Hyundai Mobis RKE-4F16 Wireless Key Fob for Hyundai Sonata models 2014-Present.

ICAO Selcal (also known as AVCALL, ANNEX 10, or just SELCAL) is a HF/VHF aviation selective calling system used by ground stations to initiate radio communications with aircraft.

ICARUS aims its services primarily at scientific groups that perform basic and application-oriented research with migrating animals.

ICV is a NATO-operated VLF transmitted located in the island of Tavolara, Sardinia, Italy.

ILS Marker Beacons are used by aircraft for Instrument Landing Systems, transmitted by an upward-facing directive antenna at known distances along the approach path.

Radiosonde launched on a weather balloon.

ALIS-2, also known as RS-ARQ, RS ARQ 240, and MERLIN, is an improvement of the original ALIS system. ALIS-2 is used in the Rohde & Schwarz MERLIN modem.

RF interference from nearby induction cooker can sometimes be mistaken for a real LF or VLF transmission.

key opener commonly used in industrial applications

Inmarsat Aero is the protocol that's used to link ground stations with aircraft via Inmarsat's satellite link. This protocol carries digital voice, fax and low speed data such a…

IsatM2M Service operated by Inmarsat on existing Inmarsat-D/D+ infrastructure.

Inmarsat C provides two-way data and messaging communication services to and from virtually anywhere in the world. The low-cost terminals and antennas are small enough to be fit…

Inmarsat D+ (and it's predecessor, Inmarsat D) was Inmarsat's satellite paging system. The main use of the technology was in tracking trucks and buoys and SCADA applications.

Radio navigation system that allows aircraft to perform precision approaches in low visibility conditions.

iDEN is a TDMA-based digital wireless standard developed by Motorola. It is a type of trunked radio with cellular phone benefits.

ISDB-T (Integrated Services Digital Broadcasting – Terrestrial) is a new type of digital broadcasting system for providing audio, video and multimedia services. ISDB-T system wa…

A very crunchy signal coming from my Old hyundai computer screen, the sound changes depending on what is shown on the screen

Transmits train telemetry

Meteors traversing the E region of the atmosphere approximately 60 - 90 miles up create ionizing trails which can reflect and refract radio waves from commercial FM radio statio…

An Ionosonde (Also known as a chirpsounder or ionospheric sounder) is a radar that examines the Ionosphere and monitors HF propagation conditions by sweeping the HF band and rec…

IRA-ARQ, also known as BULG-ASCII and ASCII-ARQ, is a high data rate ARQ FSK system used by Bulgarian, Slovakian, and Czech diplomatic stations. The maximum speed of this mode h…

Iranian broadcast jammer with characteristic sound. Used to suppress Radio Farda and other independent stations which broadcast to Iranian audience.

Iranian Navy QPSK Modem is a QPSK mode used by the Iranian Navy. It has gone through several versions. The current version (2015) is V2 and supports speeds of 468 Bd, 936 Bd, an…

This is the L-band uplink/downlink for the Low Earth Orbit Iridium Satellite Constellation. This system is used for satellite based phone calls.

D-AMPS, also known as IS-54 and IS-136, is a second generation (2G) mobile phone system standard which develops on analog AMPS, a 1G standard. This system is also colloquially k…

Inmarsat's M2M data service for SCADA asset tracking and reporting.

Ionospheric Scattering (ISCAT) mode used for weak signal long distance radio contact by meteor and Ionosphere scattering.

An ISM band device such as a power meter or a wireless doorbell.

Data returned from a consumer weather sensor using the AlectoV1 protocol.

Israeli Intelligence based FSK VFT.

The Israeli Naval Hybrid Modem is based on the MIL-STD-188-110 Serial Standard. Has characteristic preamble with 4/6 Tone and 18 QPSK parallel mode before 110 Serial transmissio…

Israeli based VFT transmission, most likely used by Israeli government or military.

Data signal thought to originate from Japanese Military/Navy

The Japanese Slot Machine (Enigma Designation XSL) is a simplex system used by the Japanese Maritime Self-Defense Force in Ichihara, Japan.

Jim Creek Naval Radio Station is used by the US Navy to transmit commands to distant submarines.

JORN is an Australian OTHR system that operates uniquely in that it's radar bursts include an intro tone before the burst.

JJY, also known as JJY-40 and JJY-60, is the call sign for a pair of longwave Time Signal stations in Japan.

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 sa…

JS8Call is an extremely-weak-signal amateur radio communication mode based on FT8. It allows FT8 to be used for conversations and message relaying.

JT4 is a 4-FSK extreme weak-signal mode which is designed especially for Earth-Moon-Earth communications. It is part of the WSJT-X software.

JT65 is an amateur radio QSO communication protocol developed by Joe Taylor, K1JT . JT65 has 3 submodes: JT65A, JT65B, and JT65C. The most popular submode of JT65 is JT65A. JT65…

JT6M is part of the WSJT suite of digital weak signal software applications developed by Joe Taylor, K1JT

JT9 is a 9-FSK mode for making contact (QSO's) under extreme weak-signal conditions. It is part of the WSJT-X software.

JTMS is a meteor scatter mode that uses MSK. JTMS behaves similarily to FSK441.

FleetSync is a manufacturer specific signaling standard which includes a number of features: unit ID, status, emergency button, inhibit, status check, GPS, and selective calling.

KG-STV is an image transmission mode developed by JJ0OBZ in Japan.

Kia SVI-JFRGE04 Keyless entry transponder used for multiple Kia models, for model years 2014-2020

Kiwi is a telemetry mode developed by CNES used on amateur rockets and radio balloons in France.

The KY57/58/68 Transmission Security Device is designed to protect the transmission of voice or data in the form of audio tones. Uses CVSD modulation like Securenet.

2FSK transmission mode 20828 baud, Information is transmitted by the code "Manchester", respectively, the data transfer rate is twice lower (7785.63 baud).

Lentus is an extremely slow QRP mode developed by Patrick Lindecker F6CTE used to transmit QRP's at very low power. Each 43-character (75 bit) transmission takes roughly 5 minut…

Cospas-Sarsat downlink from polar-orbiting weather satellites. The International Cospas-Sarsat Programme is a satellite-aided search and rescue initiative.

VLF RF emissions from lightning in the atmosphere that can affect up to HF frequencies and beyond depending on strength. Has a popping crackle sound with both USB and AM modes o…

Link-11 (Also known as ALLIGATOR, STANAG 5511, TADIL-A, MIL-STD-6011, and MIL-STD-188-203-1A) is a Tactical Data Link standard (formerly known as Tactical Digital Information Li…

This is the UHF band variant of Link-11, which is transmitted on a FM carrier. The FM-demodulated baseband is identical to the HF Link-11 waveform.

The LMS-6 is a radiosonde developed by Lockheed Martin which contains a temperature, barometric pressure (On the 1680 MHz models only), and humidity sensor for upper air weather…

Logic Trunked Radio, is an analog trunked radio format developed by EF Johnson Company.

This signal comes from Logitech(R) Brand wireless mouse and keyboard combo unit.

LoJack is a vehicle tracking system that allows vehicles to be tracked by police, with the aim of recovering them in case of theft via a small radio transceiver clandestinely in…

LoRa (Long Range) is a proprietary low-power wide-area network modulation technique.

LORAN (short for LOng RAnge Navigation) is a hyperbolic radio navigation system.

This is an electromagnetic emission from a budget wireless bicycle computer speed sensor. It is not a traditional radio signal, but rather a magnetic induction pulse generated b…

The Low Rate Picture Transmission (LRPT) is a digital transmission system, commonly transmitted by METEOR-M satellites, used to deliver weather images and data.

LRS restaurant pagers operate in the PMR446 band, most commonly on 446.15625 MHz. The system uses narrowband FM (NFM) modulation with a 12.5 kHz channel bandwidth, transmitting …

Band 88 FDD

An open source digital mode developed for amateur and other radio applications.

Telemetry signal transmitted by M20 radiosondes

Magnetron produces regularly repeating pulses of microwave energy. These pulses have a defined repetition rate, a stable peak amplitude, and a consistent pulse width.

The Marconi Selenia 25-Tone Modem is a military modem developed sometime around 2003 by Marconi Selenia Communications (Now Finmeccanica). It supports ECCM capability and transm…

SKE126-01 Key Fob used for multiple Mazda models between 2006-2014. Manufactured by Mitsubishi Electric Company.

Mazielka (X06) is a diplomatic selcall system used by the Russian Ministry of Foreign Affairs. Used to alert that a Serdolik transmission is going to occur soon, usually on a di…

MD-522 (Also known as MIL-M-55529A) is a synchronous FSK mode built into GRC-MD522 teletypewriter sets and used for wirelessly transmitting ASCII information. MD-522 has a narro…

MD-674, also known as Wireline FSK, is a very old United States Military FSK Modem from the 1960's. Uses 85 Hz FSK shift. Speeds of 50 Bd, 75 Bd, 100 Bd, and 150 Bd have been lo…

Motorola's MDC-4800 is a data protocol that was used in ARDIS and DataTAC Networks as well as in MDT networks. RD-LAP was derived from this mode. Also known as Motorola Mobile D…

MDC (Motorola Data Communications), also known as Stat-Alert, MDC-1200 and MDC-600, is a Motorola two-way radio low-speed data system.

Weather balloon (radiosonde) telemetry data.

Weather balloon telemetry data.

A variant of the NOAA HRPT signal, which has a different data structure and better low-signal handling characteristics.

Meteosat WEFAX is a WEFAX used to transmit satellite images via Meteosat Satellites. WEFAX was introduced with the first Meteosat in 1977.

A high-speed digital link used by METOP weather satellites for direct data dissemination.

Popular antenna analyzer among ham operators and the like. Output power is only ~20mW so if heard, source is nearby. Other MFJ models may be similar.

Weather balloon telemetry data. The LORAN-C signal is mixed into the carrier.

Microwave motion sensor uses a small Doppler radar module to detect movement. The sensor emits microwave signals and monitors the reflected waves.

MIL-STD-110-342 was a US Dept. of Defense standard for a 16 channel VFT teletype transmission. This mode was officially cancelled as of December 5th, 1995.

MIL-STD-188-110 Appendix A is a 16-tone OFDM PSK signal used to transmit data. As of 110C revision, this mode is being phased out.

MIL-STD-188-110 Appendix B is a 39-tone OFDM DQPSK mode used to send data and voice.

MIL-STD-188-110 Serial is a US Department of Defense standard for HF Communications, Serial PSK mode. Can transmit both data and voice with a range of interleaving and speed mod…

UHF FHSS Downlink of Milstar, a US joint military service satellite communications system that provides secure, jam resistant, worldwide communications. Nicknamed 'Waterdroplets…

MMP-4800 was a MDT (Mobile Data Terminal) protocol developed by Canadian company Mobile Data International (MDI) in 1982 for their Mobile Data Terminals. Used by public safety a…

MOBITEX is an OSI based open standard, national public access wireless packet-switched data network.

MODAT is a 7-tone Automatic Number Identification (ANI) status system used by handheld radios. It provides unit ID and emergency statuses to receiving radio sets when transmitted.

The Modernised High Frequency Communications System (MHFCS) is an Australian Department of Defense HF System for their military communications network. Also known as AUS MIL ISB…

Fire alarm control panel built for the United States of America's Department of Defense.

Monitor-2 is a Russian 3u Cubesat used for cosmic flare observation. It is most likely only active when above Russia.

CW Morse Code is the simplest form of transmission found virtually all over the RF bands for a variety of uses. The most common use of this is for Call-sign Beacons by both Amat…

Motorola's ASTRO 25 High Performance Data Air Interface allows Motorola ASTRO 25 HPD modems to transfer data at up to 96 kbps over a 25 kHz channel in the 700 MHz or 800 MHz bands.

Motorola SECURENET ("analog" encryption) was a secure voice option for conventional and Motorola Type II trunked systems, encoding the voice using 12kbps CVSD and encrypting the…

Radio trunking control channel.

Experimental Multi‑Parallel Differential Amplitude Shift Keying (MP‑DASK) narrowband data mode for HF/VHF amateur radio text communication, created by amateur radio operator 6L5…

MPT1327 (Ministry of Posts and Telegraph 1327) is a signaling protocol standard for analog trunked radio

Remote key less entry fob for Honda car's with door lock, Unlock and remote boot/trunk open feature (keyfob data may be same as other manufactures)

MRZ-3MK is a Russian weather radiosonde.

MRZ-N1 is a russian weather radiosonde.

MSF is a time signal station in Anthorn, United Kingdom, which broadcasts the UK national time reference

MSK144 is a Minimum Shift Keying FSK signal used for amateur radio meteor-scatter contacts. It transmits 144 bit long packets at a baudrate of 2000 bps using frequencies 1000 an…

MSM-1250 (Medium Speed Modem) is a 10 FSK-2 OFDM digital data protocol used by the stand-alone modem "SkyFax", used to transmit and receive faxes on HF.

MT63 is a Orthogonal Frequency Division Multiplexed (OFDM) digital data mode aimed for use in high noise environments.

MFSK is a generic family of frequency shift keying digital transmission methods using more than the two tones of BFSK (binary FSK). Many digital signals, especially on HF, use M…

Multiplite sub-Nyquist Sampling Encoding (MUSE) also known as Hi-Vision was a early analogue high-defition television standard developed by NHK Science and Technical Research La…

Multiplexed Analogue Components (MAC/packet) family was a analogue television broadcasting standard. Replaced by digital broadcast.

Multitone Paging signal, developed by Multitone Electronics in the UK. Uses similar coding to POCSAG but the headers are different and only work with Multitone's range of paging…

Narrow-Bandwidth Television (NBTV).

NATEL is a 5-tone selcall mode defined by Scandinavian National Telephone recommendations.

The National Public Alerting System (NPAS), branded to consumers as Alert Ready, is a national warning system in Canada. The tone does not carry any information to be decoded. I…

Narrowband Internet of Things (NB-IoT) is a Low Power Wide Area Network (LPWAN) radio technology standard developed by 3GPP to enable a wide range of cellular devices and services.

Near-field communication (NFC) is a set of communication protocols that enables communication between two electronic devices over a distance of 4 cm (11⁄2 in) or less.

NICAM is used to provide digital stereo audio alongside PAL video for television broadcasts.

NXDN is a digital narrowband trunked radio protocol used in commercial, business & industry, transport and Public Safety professional radio systems.

Used in analog walkie-talkies and communication systems.

Wireless entry rolling code car key.

Naval Radio Transmitter Facility (NRTF) transmits encrypted commands to submerged US submarines.

The Direct Sounder Broadcast (DSB) is an auxiliary telemetry downlink from NOAA Polar Operational Environmental Satellites (POES), transmitted alongside Automatic Picture Transm…

An analog signal broadcast from NOAA ITOS polar satellites that transmitted images from the VHRR radiometer.

A digital link to transmit images and other data collected from the satellite at a high resolution.

The Nokia Adaptive Message Terminal, also known as Nokia Adaptive Burst Modem and Kryapp 302, is a Finnish encrypted messaging system suggested to be used by Finnish Intelligenc…

A Non-Directional Beacon (NDB) is a ground-based, low frequency radio transmitter used as an instrument approach for airports and offshore platforms.

North Korean Diplomatic FSK link, teletype radio diplomatic usage. Also known as DPRK-FSK, KRE-FSK, DPRK-ARQ, and KEGURI. Has a FEC stream mode and a burst ARQ mode.

North Korean Diplomatic PSK link. Also known as KRE-PSK. Four speed modes have been seen, 150 bd, 300 bd, 600 bd, and 1200 bd. All use BPSK modulation. The main identifying feat…

Noise jammer with a carrier than tends to switch frequencies slightly lower and higher than the main signal frequency. Commonly found on 6.6 MHz

The North Korean Siren Jammer is among the signal disruption techniques employed by North Korea, commonly targeting shortwave radio stations.

TACAMO (take charge and move out) is the back up communications system to the US nuclear submarine fleet in case an attack on land based transmitters disables them. A rotating f…

Naval Radio Transmitting Facility (NRTF) sends encrypted commands to submerged US naval submarines in the Pacific.

National Television System Committee (NTSC) Television broadcast is an analogue television broadcast mode. Currently being phased out in parts of the world in favor of digital b…

Naval Communication Station (NCS) Harold E. Holt. Used jointly by the Australian and United States navies to transmit encrypted orders to submerged submarines in the Pacific.

OFDM NBTV is an analog technique, in fact it is a true Fuzzy design as well. The transmission technique used is quite different from conventional TV

OLIVIA is an amateur digital teletype mode designed by Pawel Jalocha SP9VRC in 2005. Its goal was to be effective even in poor propagation conditions.

One Beep, Two Beeps is a nickname given to a signal emitted by the Norwegian Navy communications center in Bodø

Cheap RC Cars with only for buttons (Forward, Reverse, Left, Right) Typically use 27Mhz or 49Mhz as the transmit frequency. There's typically no channel switching system on the …

OpenSky is an encrypted TDMA protocol that is heavily used but is being phased out by the Pennsylvania State Police. No one other than the intended user has been able to decrypt…

This is a signal from a OpenWay Centron Electric 'Smart Meter'. Each house is now fitted with one of these, and they are strong - typically 50 dB above the atmospheric noise level.

OPERA Ad-Hoc Data/Beacon. The system is unique in that utilizes a serial data stream and Manchester coding, its therefore impossible to lose lock and its extremely robust in dis…

Orbcomm satellites are used for monitoring and sending short text messages.

Orbcomm digitized mobile satellite-based telephone signal intercepted over Hawaii, preceding NOAA 19 pass.

Musical transmission originating from the OTP-2 Cubesat

Enigma designation P03 is a family of digital PSK modes, used by the "Polish 11" numbers station operator, which is likely a Polish intelligence agency.

Enigma designation P07 is a custom digital mode used by the "Russian 7" numbers station operator which is likely a major Russian intelligence agency.

Packet, also known as FSK300, AFSK1200, BPSK300, QPSK600, BPSK1200, QPSK2400, AX.25 and IL2P, is a packet based protocol derived from X.25 and HDLC computer network protocols. P…

PACTOR-I is a digital data protocol combining elements of PACKET and AMTOR ARQ.

PACTOR II is an advancement of PACTOR I. It is up to 8 times faster than PACTOR I.

PACTOR III introduces 6 speed levels that provide higher throughput and improved robustness compared to PACTOR I and II. PACTOR III is on average 3.5 times faster than PACTOR II…

PACTOR IV is the newest iteration of the PACTOR series, advancing from PACTOR I-III. It is 1.5x-3x faster than PACTOR III, and has 10 speed levels.

[POCSAG 1200] Used in places like hospitals and other areas. Transmits at 1200 bps.

An unknown use of pager data thats sent in the form of frames, possibly used to send SSTV or confidnetial Faxes over a re-purposed POCSAG or FLEX transmitter.

Phase Alternating Line (PAL) Analogue Television Broadcast. Now phased out in most of the world.

Panther-H is an intelligent frequency hopping transceiver developed by Racal (now Thales Group). Has a signature 8-burst SOC (Start Of Conversation) sync procedure. Used in Pant…

PAX and PAX2 are developed by Patrick Lindecker F6CTE in 2005, and was derived from Olivia. It utilizes the AX.25 protocol that PACKET uses, and had a minimum SNR of -10dB. Can …

PSK is a digital teletype mode based on Phase-Shift Keying (PSK) modulation. The most popular amateur radio PSK mode is PSK 31.

PI4 (PharusIgnis4) is a 4-MFSK mode designed for amateur radio beacons. It is designed to work via different propagation modes.

Piccolo was a MFSK system developed by the UK Foreign and Commonwealth Office (FCO) to communicate with foreign embassies and UK military stations around the world. No longer used.

PLUTO II is an Over The Horizon Radar located in the Sovereign Base Area just outside RAF Akrotiri in Cyprus. PLUTO II is very active in Europe.

POCSAG (Post Office Code Standardisation Advisory Group), also known as Super-POCSAG, Radio Paging Code No. 1 or RPC1, is a one-way 2FSK paging protocol that supports 512, 1200,…

A Russian over the horizon radar, also known as "Sunflower"

POL-ARQ was a duplex ARQ system used by Polish and Italian diplomatic services. This system uses the CCIR 476-4 alphabet with polatiry retained. No longer in use.

Also known as F11, this is a one-way broadcast system that was used by one of Polish intelligence agencies for delivery of messages to their operatives abroad on fixed schedules.

Signals sent from portable traffic lights that are often used at roadworks.

Positive train control (PTC) is a system of functional requirements for monitoring and controlling train movements as an attempt to provide increased safety.

possible quarry telemetry observed on 462.775, appears to pulse every second

PRC-16 is a Chinese sourced PSK data link, traced to Shanghai. Suspected user Chinese Military.

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 refl…

Primex Wireless Time Sync is a VHF Time Synchronization signal used in Primex Wireless's XR Series.

Dump of satellite data to Redu, Belgium ground station from the PROBA (Project for On-Board Autonomy) 1, 2, and V ESA satellites.

Project 25 (P25 or APCO-25) is a trunked radio standard developed by The Association of Public Safety Communications Officials International (APCO-25) for use with public safety…

ProVoice is a digital voice mode used in EDACS trunked systems.

Also known as PSK paging, is a signal that allows side-by-side PSK to exist in AFSK paging links, allowing for more dynamically processed DSP available.

PSK-AM is an amateur digital mode developed by Patrick Lindecker F6CTE in 2002/2003, and incorporates FEC interleaving. PSK-AM uses the modulation of PSK10/31 with the FEC of SI…

PSK2K is a meteor scatter type of mode written by DJ5HG Using a modulation scheme of BPSK at 2000 Bd.

Signal used for remote control (RC) Toys.

Pursuit series wireless car alarm entry key, for use on vehicles equipped with Pursuit Series Car Alarm System.

The Q-MAC HF Modem is a military modem developed by Q-MAC (acquired by Barrett Communications). It uses OFDM with a BPSK sync channel in a gap of the signal.

Q15X25, also known as NEWQPSK, is an experimental amateur radio packet modem developed by Pawel Jalocha SP9VRC. Q15X25 is a OFDM QPSK implementation of the AX.25 Packet protocol…

Q65 is a 65-FSK extreme weak-signal mode which is designed for Earth-Moon-Earth communications and fast-fading propagation modes such as tropospheric scatter, rain scatter and t…

High speed modem for QO-100 (Es'hail 2) amateur satellite narrow transponder.

This signal originates from the Silicon Instruments Si1000 Software Defined Radio (SDR) that is a component of the 3DR Telemetry Radio, sold for use as a data link between a com…

A digital text message protocol included in the stock firmware of some Quansheng brand handheld radios to send up to 30 characters in a short packet type message.

RAC-ARQ, also known as MEROD and RACAL-ARQ, is a teleprinter system by Racal, used in MEROD devices. MEROD stands for Message Entry and Read Out Device. Hasn't been seen since 2…

Aircrafts radar altimeter.

Motorola's Radio Data Link Access Procedure (RD-LAP) is a 1G protocol that was used in ARDIS and DataTAC Networks, and is still used in some MDT's, as well as gas companies, pol…

Radio Data System (RDS) and its North American variant, Radio Broadcast Data System (RBDS), are data modes transmitted on subcarriers of commercial FM radio station transmissions.

Generic positioning, navigation, and timing (PNT) signals transmitted by global/regional navigation satellite system (GNSS/RNSS) and Satellite-Based Augmentation System (SBAS) c…

The Radio Telephone Network C (German: Funktelefonnetz-C, abbreviated as C-Netz), was a first generation analog cellular phone system deployed and operated in Germany (at first …

RTTY (Also known as Baudot or ITA2) uses the Baudot 5-bit alphabet with FSK to send text messages over the shortwave. This mode is gradually dying out in favor of more robust mo…

A radio‑relay (microwave) link using small parabolic antennas is a short‑range, high‑capacity point‑to‑point microwave connection commonly deployed when fiber is unavailable or …

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, possibl…

Control signal for grass sprinkler watering system

RBU is a time code radio station located in Moscow. It transmits a continuous 10 kW time code on 66.66 kHz.

RDL is a Russian VLF station located in Krasnodar. It is one of the few VLF stations that changes modes during routine transmissions.

RDFT is an amateur radio digital mode used to transmit files.

ReFLEX is a two-way paging variant of FLEX.

Relocatable Over-the-Horizon Radar (ROTHR), also known as AN/TPS-71, is an OTH Radar used by the United States Navy that uses bistatic ionospheric backscattering for wide area s…

Radio frequency heating and welding equipment may radiate interference which can be picked up by radio receivers. On a waterfall display, it usually appears as wobbly peaks that…

Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. The tags contain electronically-stored informatio…

A sort of SCADA signaling method used to cooordinate traffic or other road works using external NFM transmitters. Can also be shared with road commission vehicles and related t…

Robust PACKET, also known as HF-APRS, RPR, Winlink RMS, and APRSlink, is an OFDM version of the amateur mode PACKET which is optimized for shortwave use. This mode was developed…

ROS is an amateur radio teletype free running QSO mode designed for low signal/high noise conditions.

RTTYM, developed by Nick Fedoseev (UT2UZ) in 2005, is a digital mode derived from Olivia. It aims to deliver a compromise of speed and performance. RTTYM is about 4x faster tha…

RUM-FEC, also known as ROU-FEC and SAU-FEC, is a FSK FEC system used by Romanian diplomatic services. This is no longer used today, replaced by MIL-STD 188-110 Serial.

RUM-MOI FEC, also known as RUM-MIL 115.76 Bd, is a FSK FEC mode used by the Romanian Ministry of Internal Affairs, supposedly under military use. This is no longer used today, r…

Russian Diplomatic 3 channel VFT PSK running at 64 Bd. Enigma M42 designation

Also known as F06, this is a one-way error-correcting broadcast system, used by one of Russian intelligence agencies for delivery of messages to their operatives abroad on fixed…

Also known as F01, this is a digital FSK mode used by Russian intelligence to deliver encrypted messages to their operatives abroad. Transmissions usually happen on fixed schedu…

A supposedly Russian HF data mode with MFSK, OFDM and frequency sweeps, resulting in an interesting spectrogram and sound.

Slow 20-baud FSK signal with very large 7 kHz frequency shift. Used by Russian military.

Over The Horizon radar with a very similar signal structure as Ghadir. Operating in west Russia.

Russian telemetry system, transmitted over the overhead power lines.

RWM is a Russian shortwave time signal station.

This is what the signal of a military S-Band (In this case 2.4 GHz) RADAR and WiFi intentional interference (Jamming) device looks like. This signal is generated by a DDS system…

The MHF-50 MFSK Modem by Saab Grintek Technologies in South Africa is a data modem that utilizes RTTY, 2-FSK, and 33-MFSK to transmit data

Interference from a samsung washing machine. Manifests as lines and bulb-looking patterns across the spectrum.

Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio)

Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio) and is activated less often as the other Swedish transmitters used for VLF …

Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio).

Schneider Trio E-Series Modems are industrial modems used for SCADA, telemetry, and other ASCII-based messaging applications.

Sequential Colour with Memory (SECAM) Analogue Television Broadcast. Now phased out in most of the world.

Secondary surveillance radar (SSR)is a radar system used in air traffic control. A surveillance radar system which uses transmitters/receivers (interrogators) and transponders.

SECOR 4 ( COSPAR ID: 1965-027B ) was a SEquential COllation of Range series satellite, and is occasionally active when receiving adequate solar power on it's panels. It is not c…

These are samples from the Sensus Water meters. They are a FHSS ASK encoded data transmission for purposes of providing municipalities water meter telemetry (for billing how muc…

Serdolik is a MFSK signal used by the Russian diplomatic service.

Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio).

SI-ARQ, also known as ARQ-S and ARQ-1000S, is a simplex ARQ system designed by Siemens formerly used by Austrian and Indonesian diplomatic services. No longer used today.

SI-FEC, also known as FEC-S, FEC 1000 Simplex, and FEC-1000S, was the FEC variant of SI-ARQ, and was only used under extremely poor propagation conditions. SI-FEC was developed …

Radio signal used by MRI machines to excite protons and obtain their response.

CHX200, also known as Siemens CHP200 and PRC-921/GY, is a backpack HF ECCOM transceiver, designed and built by Siemens.

SIGFOX is a IoT wireless network system utilizing ETSI's specification for Low Throughput Networks (LTN) and Ultra Narrow-Band (UNB) modulation.

The SIMONe radar is a meteor detection system that is operated in multiple research sites around the world. It uses continuous spread-spectrum coded transmissions which gives it…

Russian telemetry system, transmitted over the overhead power lines.

Single-sideband voice is a subtype of AM voice modulation. It is used in HF amateur bands and for weak signal VHF and UHF voice, as well as aircraft weather reports.

SiriusXM Satellite Radio: Terrestrial Repeater Signal

SITOR-A (Also known as AMTOR-A) is one of two modes of SITOR, which stands for Simplex Teletype Over Radio.

SITOR-B is one of two modes of SITOR (Simplex Teletype Over Radio).

SKiYMET is a meteor detection radar which is used by many research institutes around the world. It can use different transmission parameters and can be received over long distan…

Data transmission mode developed by SkySweep Technologies in Finland. Probably used by Finnish MFA

Slow-scan television (SSTV) is a method for picture transmission used by amateur radio operators to transmit and receive images.

Interference from Smart TV units

A remote control transmission from the controller from an Elenco Snap Circuits SCROV-10 kit.

SNOTEL stations are a set of precipitation and other sensors spread across the mountains of the United States by the Department of Agriculture through the National Resources Con…

SOLRAD-7B is one of the many "zombie satellites" in orbit and is an artifact of the mid 1960's US space program. It occasionally will become active again when illuminated by sun…

Sonne (Called Consol by the Britons) was a low-frequency radio range based radio navigation system used for long range navigation.

Russian spacecraft telemetry system.

SP-14 (XP) was a 14 tone MFSK mode with origins from the Russian Intelligence and Foreign Ministry. Also known as NUM-13. Inactive since 2005, superseded by XPA.

A form of SSTV that directly modulates an image to IQ by scanning across it so it shows up when viewed using a waterfall. Used by Hams for experimentation methods.

SPREAD, also known as AUTOSPEC Mk2, SPREAD-11, SPREAD-21, and SPREAD-51, was a FEC system used by Romanian diplomatic stations and the Brazilian Navy and shore stations. SPREAD …

STANAG 4197 is a NATO QPSK OFDM signal used in ANDVT modems that transmit encrypted digital voice over HF.

STANAG 4285 is specified by the NATO (North Atlantic Treaty Organization) Military Agency for Standardization in "Characteristics of 1200 / 2400 / 3600 Bits per Second Single To…

STANAG 4415 is a NATO standard for robust, non-hopping digital data communication, used on severely degraded HF channels with large Doppler and multipath spreads.

STANAG 4481, also known as CRATT, Link-4, and NATO-75, is specified by the NATO (North Atlantic Treaty Organization) Military Agency for Standardization as a "Minimum technical …

STANAG 4529 a modification of STANAG 4285 to deliver data and voice in 1240 Hz of bandwidth at rates of up to 1800 bps.

STANAG 4539 or MIL-STD-188-110B/C Appendix C is a HDR (110B) / MDR (110C) serial PSK/QAM signal that can reach speeds up to 9600 bps (12800 bps with no interleaving).

STANAG 5065 is defined as "Minimum Standards for Naval Low Frequency (LF) Shore-To-Ship Surface Broadcast Systems", with two primary protocols, FSK75 and MSK300.

STP403 is a bus PIT system used to update digital displays at bus stops. STP403 was developed by French companies INEO and CESATEC.

SuperDARN (Super Dual Auroral Radar Network) is an international radar network used for scientific purposes. The network is used to study plasma convection in the upper atmosphere.

Supervisory Control And Data Acquisition (SCADA) is a control system architecture that is used in industrial applications for computerized automated systems. Wireless telemetry …

SWED-ARQ, also known as ARQ-SWE, was a Swedish simplex ARQ system used by Swedish diplomatic services. This protocol supported three packet lengths and was able to change packet…

Commonly experienced interfering RF emissions from switching electronics (i.e. switched-mode power supplies, power converters, digital electronics, etc.) which use inductors (co…

Radio navigation technology that measures the slant range (distance) between an aircraft and a ground station by timing the propagation delay of radio signals.

TDF, also known as ALS162, is a time signal transmitted on the former carrier of France's France Inter longwave AM radio station on 162 kHz.

TETRA is a professional mobile radio and two-way transceiver (walkie-talkie) specification

Tetrapol is a digital professional mobile radio standard for digital voice and data communication used by public safety and military throughout Europe. Tetrapol was originally d…

Thales SALAMANDRE (using HFXL waveform) uses up to 16 separate contiguous or not-contiguous narrowband HF channels for high datarate military and tactical communications. Operat…

Thales Système 3000 is a HF modem capable of many different modes of transmission. It has a unique preamble and format to it's signals.

Thales Système 3000 Skyhopper is the frequency hopping mode of the Système 3000 Modem. Characterized by it's very short bursts and frequency hopping behavior.

Voice Scrambling mode from Thales Système 3000 HF Modem. Has characteristic PSK and MFSK bursts at the beginning and end of a voice transmission.

"The Air Horn" is a Russian military commandment network serving the Western Military District, which also serves the same purpose as the buzzer. It was first heard in 2017, bro…

Channel marker of a Russian military station nicknamed "The Alarm". "The Alarm" is a Russian military commandment network serving the Western Military District. So far, apart fr…

The Buzzer, call-sign NZhTI (formerly ANVF, ZhUOZ, MDZhB and UZB-76), is a Russian Military Commandment system signal used to broadcast diplomatic ciphered messages known as "mo…

"The Goose" is a Russian military commandment network serving the Western Military District. It broadcasts on 4310 kHz during daytime, changing to 3243 kHz for nighttime.

The Pip is the nickname given by radio listeners to a shortwave radio station that broadcasts on the frequency 5448 kHz by day, and 3756 kHz during the night. It broadcasts shor…

THOR is an adaptation of DominoEX with MFSK16 binary varicode and FEC.

THROB is a unique data mode that relies heavily on DSP techniques, using MFSK and AM modulation techniques together.

TPMS (Tire-Pressure Monitoring System), more specifically Direct TPMS (dTPMS), is a system that uses pressure sensors to monitor tire pressure on vehicles.

A first generation analogue mobile cellular system which operated in the United Kingdom and a handful of other countries in Europe. It is also the EU's form of AMPS.

Wireless entry rolling code car key.

AFSK Modulated signal with 2400Baud for traffic light control. Contains R09.16 telegrams as specified per VDV Standard 420 .

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…

TT2300, also known as TT2300B, TT2300-ARQ, TRA-2300, and TPLEX, is an 8MFSK synchronous system developed by Thrane & Thrane of Denmark (acquired by UK defense firm Cobham in 2012).

These signals are narrowband technical carriers transmitted by the Thor‑5 satellite in the Ku‑band, close to 11700 MHz. They are part of the satellite’s TT&C (Telemetry, Trackin…

TWINPLEX, also known as F7B4 and TWINPLEX-SITOR, was a diplex 4-FSK ARQ mode developed by Mackay Radio and Telegraph Company, based in New York City, in the early 1950's. TWINPL…

UHF Vehicle Location System

The UIC radio is an analogue radio, which consists of lineside and mobile (trainborne) equipment. Radio systems following this basic subset allow for simplex and duplex voice co…

UK AM Data System (UK-AMDS) was developed by BBC Research and Development in 1984 as a way to transmit low bitrate data on BBC Radio 4's LF AM carrier. Elements of this system w…

UK GOV/MIL "WinDRM51" variant. Unknown purpose, But link between UK & Cyprus has been found some years ago.

A 48k or 24k baud OQPSK signal that is strongly suspected (through numerous circumstantial pieces of evidence) to be either an experimental or active P2P RF link between financi…

Unable to identify this transmission. It was found in Hawaiian airspace operating on band reserved for military transmissions. Some sort of FSK? Bears resemblance to Unknown 707.

UTC (Coordinated Universal Time) time standard transmission from NIST (National Institute of Standards and Technology) stations WWV in Fort Collins, Colorado USA (2.5, 5, 10, 15…

Weather balloon (radiosonde) telemetry data.

Valsala Radiosonde RS80. This is an analog weather balloon radiosonde. Measures Temperature, Pressure and Humidity.

RS92-KL and RS92-K are analog radiosondes built by Vaisala in Finland. These radiosondes are used for weather balloons.

Weather balloon (radiosonde) telemetry data.

VARA HF is a sound-card mode used to exchange traffic (Mostly Winlink traffic) on the HF bands

VDEW is a 5-tone selcall mode defined by the Vereinigung Deutscher Elektrizitaetswerke in Germany.

Data transmitted from a vehicle counting system installed in car parks. The data is frequency hopping over 10 MHz.

Two-way 100 Bd/500 Hz Russian Telegraph system, attributed name VEZHA-C (Tower-S), usage claimed to be by Russian Ministry of Communications (MinComSvyaz Rossii). Possible usage…

VDL-M2 (Known as VDL2 or VDLM2) is a means of sending information between aircraft and ground stations. VDL Mode 2 is the only VDL mode being implemented operationally to suppor…

A type of radio navigation system used by aircraft. It is distinctive in that the center frequency is flanked by two FM waves.

Used to interrupt AM boardcast stations such as Radio Free Asia, Radio Đáp Lời Song Núi as well as Radio Sweden.

VISEL, also known as YUG-MIL 120.9 Bd, FEC-12, and YUG-MIL FEC, is a synchronous teleprinter system used by the former Yugoslav military. No longer active today.

MCT-201 is a Miniature Pendant PowerCode Wireless Transmitter by Visonic. It is designed for emergency and control applications in wireless security systems, and home automation…

VOICE is a MFSK mode developed by Patrick Lindecker F6CTE in 2006, and was derived from Olivia. It was designed for blind or partially sighted amateur radio operators.

Analog Voice Inversion Scrambling divides the spectra into multiple bands and swaps them.

Radiofax (Also known as Weatherfax, HF-FAX, WEFAX, and Weather Facsimile) is a slow scan analog image transmission mode used for the transmission of weather charts and meteorolo…

The E084 is a radiosonde designed in 1990 by Deutsche Wetterdienst. It broadcasts a temperature reading at 403.05 MHz via a FM-modulated tone which changes pitch depending on th…

Use to monitor and control warning sirens

WiMAX is a family of of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) o…

WinDRM is an amateur radio derivation of the Digital Radio Mondiale (DRM) digital voice and data transmission protocol. Also known as HamDRM, and Digital SSTV.

434.225 MHz MegaHertz (MHz) 10^6 Hz

Wireless Smart Utility Networks (Wi-SUN）

The freezer temperature is requested by a master at regular intervals, and the slave attached to a freezer responds. The communication format appears to be a variant of chirp sp…

This is a placholder for the WLO channel marker and associated signals. -- Mbeam ( talk ) 18:36, 22 May 2016 (NZST) More information located on its originating home page : http:…

Weak Signal Propagation Reporter.

WWVB is the lowest frequency time signal in the USA.

XMPP (Extensible Messaging and Presence Protocol) on shortwave is used by the military and are known for using MIL 188-110A Serial HF waveform and 6-bit code clear text with dua…

Yachta or Yakhta (Russian for 'Boat') T-219 is an analogue voice scrambler. It is unique in that an FSK sync signal is transmitted in the middle of the main signal, with the scr…

System Fusion is Yaesu's digital voice/data protocol for amateur radio, using the AMBE+2 vocoder on a C4FM signal.

The Yugoslavian 16-Tone Modem, also known as YUG-Diplo 16-Tone, is a 16 tone OFDM PSK modem used in former Yugoslavia for diplomatic use. No longer used today.

The Yugoslavian 20-Tone Modem, also known as YUG-MIL 20-Tone and YUG Diplo 20-Tone, is a 20 tone OFDM PSK modem used in former Yugoslavia for military and diplomatic use. No lon…

Military shortwave station broadcasting from the Western Military District in Russia. First heard in March 2017, this station has no channel marker, and it mainly broadcasts Mon…

Zigbee is a low-power, low-data-rate, low-latency mesh network, based on the IEEE 802.15.4 LR-WPAN standard. It is commonly used for automation and IoT devices, including sensor…

ZVEI is a family of selcall modes defined by the Zentralverband der Electrotechnischen Industrie in Germany. Selcall modes include ZVEI-1, ZVEI-2, ZVEI-3, PZVEI, DZVEI, PDZVEI a…