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 |
Payload |
Signal Type |
Notes |
| 136.260 |
ERS 20
(OV5-3)
1967-040D
2768 |
USAF test satellite |
AM - tone (unstable) |
High orbit, visible for long periods of time - (information contributed by Michael D Kenny) |
| 136.440 |
ERS 15
(NORAD lists as Secor 7)
1966-077C
2412 |
Military satellite |
AM with 1.3 kHz tone |
Incorrectly catalogued by NORAD as SECOR 7 - (information contributed by Michael D Kenny) |
| 136.800 |
Solrad 7B
(SR 7B)
1965-016D
1291 |
Solar radiation studies (launched 1969) |
AM IRIG telemetry channels |
Continuous transmission - (information contributed by Michael D Kenny) |
| 137.080 |
OPS 7898-2
(NOSS B1?)
1971-110C
5680 |
US military satellite |
CW |
(information contributed by Michael D Kenny) |
| 137.380 |
OPS 7613-1
(NRL PL176)
1969-082B
4256 |
Navigation technology |
Mixed modulation (PAM/FM/AM) |
(information contributed by Michael D Kenny) |
| 137.410 |
OPS 7613-6
(NOSS A1?)
1969-082E
4237 |
USAF test satellite |
CW |
(information contributed by Michael D Kenny) |
| 149.979 |
Oscar 29
(Transit/NIMS)
1987-080B
18362 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
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
(Transit/NIMS)
1988-074B
19420 |
Ionospheric modelling for US military (NIMS) |
FM telemetry (tones) +/- 2.4 kHz from carrier |
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
(Transit/NIMS)
1987-080A
18361 |
Ionospheric modelling for US military (NIMS) |
FM telemetry (tones) +/- 2.4 kHz from carrier |
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
(Transit/NIMS)
1988-033A
19070 |
Ionospheric modelling for US military (NIMS) |
FM telemetry (tones) +/- 2.4 kHz from carrier |
Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one) |
| 149.988 |
Oscar 32
(Transit/NIMS)
1988-033B
19071 |
Ionospheric modelling for US military (NIMS) |
FM telemetry (tones) +/- 2.4 kHz from carrier |
Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one) |
| 149.988 |
Oscar 25
(Transit/NIMS)
1988-074A
19419 |
Ionospheric modelling for US military (NIMS) |
FM telemetry (tones) +/- 2.4 kHz from carrier |
Operational frequency - Coherent transmission at 399.968 MHz - Occasionally changes between this frequency and the maintenance one) |
| 150.012 |
Unknown |
Not known |
'Wandering' CW |
Satellite in GEO, possibly graveyard orbit, also transmits 400.032 MHz |
| 150.012 |
Geosat
1985-021A
15595 |
Oceanography - wave height measurement |
CW - Doppler tracking beacon |
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
(STEP P92-1)
1993-041A
22698 |
Radar calibration |
CW - Doppler tracking beacon |
Radar Calibration satellite - Coherent transmission at 400.032 MHz, operation is intermittent |
| 150.012 |
GFO
1998-007A
25157 |
Oceanography - wave height measurement |
CW - Doppler tracking beacon |
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
(STEP P91-1)
1999-008A
25634 |
USAF space experiments |
CW - Doppler tracking beacon |
Coherent transmission at 400.032 MHz - Ceased to transmit 2003 |
| 150.012 |
USA 147
(DMSP 5D-3 F-15)
1999-067A
25991 |
RADCAL secondary payload aboard US military metsat |
CW - Doppler tracking beacon |
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
(STEP P97-1)
2001-043B
26930 |
USAF Space Test Program (STEP) |
CW - Doppler tracking beacon |
Coherent transmission at 400.032 MHz - Ceased to transmit late-2004 |
| 243.695 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 1 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.695 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 1 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.705 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 2 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.705 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 2 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.710 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 3 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.710 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 3 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.715 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 4 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.715 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 4 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.720 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 5 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.720 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 5 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.725 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 6 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.725 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 6 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.730 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 7 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.730 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 7 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.735 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 8 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.735 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 8 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.740 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
Channel usually occupied by an unmodulated carrier |
AFSATCOM Channel 9 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.740 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
Channel usually occupied by an unmodulated carrier |
AFSATCOM Channel 9 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.745 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 10 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.745 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 10 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.750 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 11 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.750 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 11 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.760 |
USA 125
(SDS-2 F4)
1996-038A
23945 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 12 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - 2007 Oct 15, USA-125 ceased to transmit AFSATCOM |
| 243.760 |
USA 137
(SDS-2 F5)
1998-005A
25148 |
Military quick reaction comms |
CW - RTTY-style data |
AFSATCOM Channel 12 transmission - 2005-2007, USA-137 and USA-125 were providing alternating coverage of the northern hemisphere from HEO - Second transmission frequency at 2242.50 MHz - Early in 2007, USA-137 ceased to transmit AFSATCOM but it was back on air early 2008 |
| 243.825 |
USA 99
(Milstar 1)
1994-009A
22988 |
USA Military communications from geosynchronous orbit |
Spread spectrum signal - +/- 64 kHz from centre frequency |
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
(SDS-3 F2)
2001-046A
26948 |
US intelligence-related satellite near 144° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(NOSS 2-2)
1991-076D
21808 |
US Military ocean surveillance |
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 |
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 122
(NOSS 2-3)
1996-029D
23862 |
US Military ocean surveillance |
AM - 4.8 kHz data tone |
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
(SDS-3 F4)
2007-060A
32378 |
US intelligence-related satellite - possibly including communications |
AM - 4.8 kHz data tone plus various test modes |
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
(SDS-3 F1)
2000-080A
26635 |
US intelligence-related satellite near 10° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F3)
2004-034A
28384 |
US intelligence-related satellite, possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F4)
2007-060A
32378 |
US intelligence-related satellite, possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F1)
2000-080A
26635 |
US intelligence-related satellite near 10° west longitude, possibly including communications |
AM - high speed (19.2 kb/s?) data transmission |
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
(SDS-3 F3)
2004-034A
28384 |
US intelligence-related satellite - possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F4)
2007-060A
32378 |
US intelligence-related satellite - possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F2)
2001-046A
26948 |
US intelligence-related satellite near 144° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(Singleton 3)
1992-023A
21949 |
Electronic Intelligence Gathering similar to USA-32 |
AM - data plus modulated tones at 4.8 and 9.6 kHz |
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
(SDS-3 F1)
2000-080A
26635 |
US intelligence-related satellite near 10° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F4)
2007-060A
32378 |
US intelligence-related satellite - possibly including communications |
AM - 4.8 kHz data tone plus various test modes |
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
(SDS-3 F2)
2001-046A
26948 |
US intelligence-related satellite near 144° west longitude, possibly including communications |
AM - high speed (19.2 kb/s?) data transmission |
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
(SDS-3 F2)
2001-046A
26948 |
US intelligence-related satellite near 144° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(SDS-3 F1)
2000-080A
26635 |
US intelligence-related satellite near 10° west longitude, possibly including communications |
AM - 4.8 kHz data tone |
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
(Transit/NIMS)
1987-080B
18362 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
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
(Transit/NIMS)
1988-074B
19420 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
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
(Transit/NIMS)
1987-080A
18361 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
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
(Transit/NIMS)
1988-033A
19070 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one) |
| 399.968 |
Oscar 32
(Transit/NIMS)
1988-033B
19071 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one) |
| 399.968 |
Oscar 25
(Transit/NIMS)
1988-074A
19419 |
Ionospheric modelling for US military (NIMS) |
Modulated CW carrier |
Operational frequency - Coherent transmission at 149.988 MHz (known to change between this frequency and the maintenance one) |
| 400.032 |
Unknown |
Not known |
'Wandering' CW |
Satellite in GEO, possibly graveyard orbit, also transmits 150.012 MHz |
| 400.032 |
Geosat
1985-021A
15595 |
Oceanography - wave height measurement |
CW - Doppler tracking beacon |
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
(STEP P92-1)
1993-041A
22698 |
Radar calibration |
CW - Doppler tracking beacon |
Radar Calibration satellite - Coherent transmission at 150.012 MHz, operation is intermittent |
| 400.032 |
GFO
1998-007A
25157 |
Oceanography - wave height measurement |
CW - Doppler tracking beacon |
Geosat Follow On - Coherent transmission at 150.012 MHz and also transmittedat 2207.5 MHz. Ceased to transmit 2008 November. |
| 400.032 |
ARGOS
(STEP P91-1)
1999-008A
25634 |
USAF space experiments |
CW - Doppler tracking beacon |
Coherent transmission at 150.012 MHz - Ceased to transmit 2003 |
| 400.032 |
USA 147
(DMSP 5D-3 F-15)
1999-067A
25991 |
RADCAL secondary payload aboard US military metsat |
CW - Doppler tracking beacon |
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
(STEP P97-1)
2001-043B
26930 |
USAF Space Test Program (STEP) |
CW - Doppler tracking beacon |
Detected being switched on and off over Europe, not continuously active - Coherent transmission at 150.012 MHz - Ceased to transmit late-2004 |
