Satellite Frequencies - DoD and the US Government

Orbital Focus - International Spaceflight Facts and Figures

Satellite Radio Frequencies

Tyneside, UK
2024 Dec 14
Saturday, Day 349

Curated by:

Robert Christy

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VHF and low UHF from US Government & Military Satellites

The US operates many satellites, using frequencies in bands from VHF and all the way upwards. The list here is concerned mainly with VHF and the low UHF frequencies up to about 400 MHz. It specifically does not include the many fixed-bandplan VHF (250-300 MHz) transponders carried by communications satellites in geosynchronous orbit.

There are several developmental satellites operating in the 136-138 MHz satellite band as well as a number using coherent frequency pairs near 150 and 400 MHz. There are also the AFSATCOM channels near 243 MHz and a number of VHF data transmissions from geosynchronous orbit and SDS satellies in highly-elliptical, high inclination orbits.

Freq (MHz)	Satellite	Transmission	Notes
136.260	ERS 20 1967-040D 2768	AM - tone (unstable)	USAF test satellite: High orbit, visible for long periods of time - (information contributed by Michael D Kenny)
136.440	ERS 15 1966-077C 2412	AM with 1.3 kHz tone	Military satellite: Incorrectly catalogued by NORAD as SECOR 7 - (information contributed by Michael D Kenny)
136.800	Solrad 7B 1965-016D 1291	AM IRIG telemetry channels	Solar radiation studies (launched 1969): Continuous transmission - (information contributed by Michael D Kenny)
137.080	OPS 7898-2 1971-110C 5680	CW	US military satellite: (information contributed by Michael D Kenny)
137.380	OPS 7613-1 1969-082B 4256	Mixed modulation (PAM/FM/AM)	Navigation technology: (information contributed by Michael D Kenny)
137.410	OPS 7613-6 1969-082E 4237	CW	USAF test satellite: (information contributed by Michael D Kenny)
149.979	Oscar 29 1987-080B 18362	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Maintenance frequency - Coherent transmission at 399.944 MHz (has been heard to transmit tones similar to the other OSCAR satellite but 2003 December 28 - this frequency was occupied by a modulated 'buzzing' signal - No longer transmitting as of 2008 Feb 1
149.979	Oscar 31 1988-074B 19420	FM telemetry (tones) +/- 2.4 kHz from carrier	Ionospheric modelling for US military (NIMS): Maintenance frequency - Coherent transmission at 399.944 MHz - Occasionally changes between this frequency and the operational one - Sometime between 2007 Dec 21 and 2008 Feb 7, the normal transmissions at both frequencies were replaced with a highly unstable CW carrier (wandering frequency + variations in strength)
149.988	Oscar 27 1987-080A 18361	FM telemetry (tones) +/- 2.4 kHz from carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one) - No longer transmitting as of 2008 Jan 1
149.988	Oscar 23 1988-033A 19070	FM telemetry (tones) +/- 2.4 kHz from carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one)
149.988	Oscar 32 1988-033B 19071	FM telemetry (tones) +/- 2.4 kHz from carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one)
149.988	Oscar 25 1988-074A 19419	FM telemetry (tones) +/- 2.4 kHz from carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one)
150.012	Unknown	'Wandering' CW	Unidentified satellite: Satellite in GEO, possibly graveyard orbit, also transmits 400.032 MHz
150.012	Geosat 1985-021A 15595	CW - Doppler tracking beacon	Oceanography - wave height measurement: Detected being switched on and off over Europe, not continuously active. Sometime around 2007, transmissions ceased to be detected but Geosat was subsequently determined to be transmitting continuously while in sunlight. Coherent transmission at 400.032 MHz
150.012	RADCAL 1993-041A 22698	CW - Doppler tracking beacon	Radar calibration: Radar Calibration satellite - Coherent transmission at 400.032 MHz, operation is intermittent
150.012	GFO 1998-007A 25157	CW - Doppler tracking beacon	Oceanography - wave height measurement: Geosat Follow On satellite - Coherent transmission at 400.032 MHz and also transmitted at 2207.5 MHz. Ceased to transmit 2008 November.
150.012	ARGOS 1999-008A 25634	CW - Doppler tracking beacon	USAF space experiments: Coherent transmission at 400.032 MHz - Ceased to transmit 2003
150.012	USA 147 1999-067A 25991	CW - Doppler tracking beacon	Military meteorological satellite: Defense Meteorological Satellite Program - Also transmits at 2207.535 MHz, 2237.5 MHz and 2252.5 MHz, and 400.032 MHz - Post-launch testing revealed interference with other equipment from the 150/400 MHz transmitters so they remained inactive (apart from further testing) until 2006 Aug 14
150.012	Picosat 9 2001-043B 26930	CW - Doppler tracking beacon	USAF Space Test Program (STEP): Coherent transmission at 400.032 MHz - Ceased to transmit late-2004
243.695	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 1, no longer transmitting.
243.695	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 1, no longer transmitting.
243.705	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 2, no longer transmitting.
243.705	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 2, no longer transmitting.
243.710	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 3, no longer transmitting.
243.710	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 3, no longer transmitting.
243.715	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 4, no longer transmitting.
243.715	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 4, no longer transmitting.
243.720	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 5, no longer transmitting.
243.720	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 5, no longer transmitting.
243.725	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 6, no longer transmitting.
243.725	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 6, no longer transmitting.
243.730	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 7, no longer transmitting.
243.730	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 7, no longer transmitting.
243.735	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 8, no longer transmitting.
243.735	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 8, no longer transmitting.
243.740	USA 125 1996-038A 23945	Channel usually occupied by an unmodulated carrier	US comms and intelligence gathering: AFSATCOM Channel 9, no longer transmitting.
243.740	USA 137 1998-005A 25148	Channel usually occupied by an unmodulated carrier	US comms and intelligence gathering: AFSATCOM Channel 9, no longer transmitting.
243.745	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 10, no longer transmitting.
243.745	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 10, no longer transmitting.
243.750	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 11, no longer transmitting.
243.750	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 11, no longer transmitting.
243.760	USA 125 1996-038A 23945	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 12, no longer transmitting.
243.760	USA 137 1998-005A 25148	CW - RTTY-style data	US comms and intelligence gathering: AFSATCOM Channel 12, no longer transmitting.
243.825	USA 99 1994-009A 22988	Spread spectrum signal - +/- 64 kHz from centre frequency	Comms: Tentative identification (may be more than one satellite) in geosynchronous orbit, can be heard with relatively simple receiver/antenna setup - in CW mode, it sounds like trickling water!
250.075	USA 162 2001-046A 26948	AM - 4.8 kHz data tone	US intelligence-related satellite near 144° west longitude, possibly including communications: One of a triplet of reported frequencies carrying similar signals from satellite in geosynchronous orbit, exact frequency not known - also reported to transmit at 256.475, 263.225, 267.550 MHz and 2242.5 MHz
250.150	USA 76 1991-076D 21808	CW carrier detectable at 250.158 MHz then a series weaker carriers up and down from this frequency at 9.6 kHz intervals between approximate limits of 250.0 and 250.25 MHz	US Military ocean surveillance: Navy Ocean Surveillance System, transmission is probably from a secondary payload - Transmission intermittent - First reported 2005 September then went into a period of silence - (the listed satellite is one of a cluster)
250.158	USA 121 1996-029D 23862	AM - 4.8 kHz data tone	US Military ocean surveillance: Navy Ocean Surveillance System, transmission is probably from a secondary payload and is on for extended periods - no reports of any switch on/off activity - (the listed satellite is one of a cluster)
251.275	USA 198 2007-060A 32378	AM - 4.8 kHz data tone plus various test modes	Intelligence-related satellite, possibly including communications: One of a pair of transmissions from a secondary payload on US classified satellite in HEO used during the test phase of the satellite up until 2008 March 13 - on March 14, USA-198 switched to its operational frequencies at 251.700 MHz and 256.375 MHz, test transmission also at 258.800 MHz, plus transmitter at 2242.50 MHz
251.325	USA 155 2000-080A 26635	AM - 4.8 kHz data tone	US intelligence-related satellite near 10° west longitude: One of a triplet of similar of transmissions from a secondary payload on a US classified satellite in GEO, signal appears to be continuous and is similar to ones from USA-179 - Also transmits at 252.675 MHz, 258.775 MHz, 268.6755 MHz and 2242.486 MHz. No longer operational.
251.700	USA 179 2004-034A 28384	AM - 4.8 kHz data tone	US intelligence-related satellite: One of a pair of transmissions from a secondary payload on US classified satellite in HEO - Switched on and off to co-ordinate coverage with USA-198 - Prior to 2008 Mar 14, USA-179 was operating alone and was providing near 8 hours' coverage per pass at this frequency - Also transmits at 256.375 MHz and 2242.50 MHz
251.700	USA 198 2007-060A 32378	AM - 4.8 kHz data tone	Intelligence-related satellite, possibly including communications: One of a pair of transmissions from a secondary payload on US classified satellite in HEO - Switched on and off to co-ordinate coverage with USA-179 - Also transmits at 256.375 MHz and 2242.50 MHz
252.675	USA 155 2000-080A 26635	AM - high speed (19.2 kb/s?) data transmission	US intelligence-related satellite near 10° west longitude: Transmissions from a secondary payload on a US classified satellite in GEO, signal appears to be continuous - Also transmits at 251.325 MHz, 258.775 MHz, 268.675 MHz and 2242.486 MHz. No longer operational.
256.375	USA 179 2004-034A 28384	AM - 4.8 kHz data tone	US intelligence-related satellite: One of a pair of transmissions from a secondary payload on US classified satellite in HEO - Switched on and off to co-ordinate coverage with USA-198 - Prior to 2008 Mar 14, USA-179 was operating alone and was providing near 8 hours' coverage per pass at this frequency - Also transmits at 251.700 MHz and 2242.50 MHz
256.375	USA 198 2007-060A 32378	AM - 4.8 kHz data tone	Intelligence-related satellite, possibly including communications: One of a pair of transmissions from a secondary payload on US classified satellite in HEO - Switched on and off to co-ordinate coverage with USA-179 - Also transmits at 251.700 MHz and 2242.50 MHz
256.475	USA 162 2001-046A 26948	AM - 4.8 kHz data tone	US intelligence-related satellite near 144° west longitude, possibly including communications: One of a triplet of reported frequencies carrying similar signals from satellite in geosynchronous orbit, exact frequency not known - also reported to transmit at 250.075, 263.225, 267.550 MHz and 2242.5 MHz
258.150	USA 81 1992-023A 21949	AM - data plus modulated tones at 4.8 and 9.6 kHz	Electronic intelligence gathering: European observations indicates that it is switched on and off on command from ground stations in Italy and Spain - also transmits at 2202.5 MHz and 2257.53 MHz, no longer active
258.775	USA 155 2000-080A 26635	AM - 4.8 kHz data tone	US intelligence-related satellite near 10° west longitude: One of a triplet of similar of transmissions from a secondary payload on a US classified satellite in GEO, signal appears to be continuous and is similar to ones from USA-179 - Also transmits at 251.325 MHz, 252.675 MHz, 268.675 MHz and 2242.486 MHz. No longer operational.
258.800	USA 198 2007-060A 32378	AM - 4.8 kHz data tone plus various test modes	Intelligence-related satellite, possibly including communications: One of a pair of transmissions from a secondary payload on US classified satellite in HEO used during the test phase of the satellite up until 2008 March 13 - on March 14, USA-198 switched to its operational frequencies at 251.700 MHz and 256.375 MHz, sharing duties with USA-179 - Test transmission also at 251.275 MHz, plus transmitter also at 2242.50 MHz
263.225	USA 162 2001-046A 26948	AM - high speed (19.2 kb/s?) data transmission	US intelligence-related satellite near 144° west longitude, possibly including communications: Reported frequency for a satellite in geosynchronous orbit, exact frequency not known - also reported to transmit at 250.075 MHz,256.475, 267.550 MHz and 2242.5 MHz
267.550	USA 162 2001-046A 26948	AM - 4.8 kHz data tone	US intelligence-related satellite near 144° west longitude, possibly including communications: One of a triplet of reported frequencies carrying similar signals from satellite in geosynchronous orbit, exact frequency not known - also reported to transmit at 250.075 MHz, 256.475 MHz, 263.225MHz and 2242.5 MHz
268.675	USA 155 2000-080A 26635	AM - 4.8 kHz data tone	US intelligence-related satellite near 10° west longitude: One of a triplet of similar of transmissions from a secondary payload on a US classified satellite in GEO, signal appears to be continuous and is similar to ones from USA-179 - Also transmits at 251.325 MHz, 252.675 MHz, 258.775 MHz and 2242.486 MHz. No longer operational.
399.944	Oscar 29 1987-080B 18362	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Maintenance frequency - Coherent transmission at 149.979 MHz (known to change between this frequency and the operational one) - No longer transmitting as of 2008 Jan 1
399.944	Oscar 31 1988-074B 19420	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Maintenance frequency - Coherent transmission at 149.979 MHz (known to change between this frequency and the operational one) - Sometime between 2007 Dec 21 and 2008 Feb 7, the normal transmissions at both frequencies were replaced with a highly unstable CW carrier (wandering frequency + variations in strength)
399.968	Oscar 27 1987-080A 18361	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one) - No longer transmitting as of 2008 Feb 1
399.968	Oscar 23 1988-033A 19070	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one)
399.968	Oscar 32 1988-033B 19071	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one)
399.968	Oscar 25 1988-074A 19419	Modulated CW carrier	Ionospheric modelling for US military (NIMS): Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one)
400.032	Unknown	'Wandering' CW	Unidentified satellite: Satellite in GEO, possibly graveyard orbit, also transmits 150.012 MHz
400.032	Geosat 1985-021A 15595	CW - Doppler tracking beacon	Oceanography - wave height measurement: Detected being switched on and off over Europe, not continuously active. Sometime around 2007, transmissions ceased to be detected but Geosat was subsequently determined to be transmitting continuously while in sunlight. Coherent transmission at 150.012 MHz
400.032	RADCAL 1993-041A 22698	CW - Doppler tracking beacon	Radar calibration: Radar Calibration satellite - Coherent transmission at 150.012 MHz, operation is intermittent
400.032	GFO 1998-007A 25157	CW - Doppler tracking beacon	Oceanography - wave height measurement: Geosat Follow On - Coherent transmission at 150.012 MHz and also transmittedat 2207.5 MHz. Ceased to transmit 2008 November.
400.032	ARGOS 1999-008A 25634	CW - Doppler tracking beacon	USAF space experiments: Coherent transmission at 150.012 MHz - Ceased to transmit 2003
400.032	USA 147 1999-067A 25991	CW - Doppler tracking beacon	Military meteorological satellite: Defense Meteorological Satellite Program - also transmits at 2207.535 MHz, 2237.5 MHz, and 150.012 MHz - Post-launch testing revealed interference with other equipment from the 150/400 MHz transmitters so they remained inactive (apart from further testing) until 2006 Aug 14 .
400.032	Picosat 9 2001-043B 26930	CW - Doppler tracking beacon	USAF Space Test Program (STEP): Detected being switched on and off over Europe, not continuously active - Coherent transmission at 150.012 MHz - Ceased to transmit late-2004
400.180	USA 217 2010-062A 37222	Trigger pulse for ground ground-based transmitters at 16s intervals	Military space technology experiments incl Store-Dump comms: Transmission from Ocean Data Telemetry Microsat Link payload to collect data from sensors on such as ocean data buoys or small, unattended ground stations. Transmits only when in range of an active sensor.