UHF-Satcom.com - C-Band monitoring (Work In Progress) Updated: (28/05/2011 13:40:47 +0100)
C-band is usually associated with 'old style' satellite TV downlinks, but there are many interesting transmissions to be heard, including Inmarsat communications, old SCPC telephone circuits, many different flavours of satellite modems and of course some TV transmissions. Some of the C-band stuff mentioned on this page comes from the HEO Molniya series of satellites.
The minimum sized dish is about a 1.2m, with a good C-band LNA and down converter. If you can find a crystal controlled converter, the phase noise of the oscillator will be low allowing for narrow band CW signals to be resolved.
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The picture on the left shows a typical C-band PLL down
converter. There is a good quality oscillator that runs at 1716.6666MHz and
is referenced from an internal OCXO. The 1.7GHz signal is amplified,
and filtered leaving only the 5150MHz which is used as the local oscillator. The NF of the converter is pretty high at around 15dB, but this is fronted by a good quality LNA, i.e. something with a <1dB NF. The converter needs about +18v to keep in lock. Pictures below show a typical setup with modified C-band LNB to tap out the 4GHz signal ready to feed to the down converter. Use a cheap LNB from eBay that has a low noise figure, remove the IF and DRO and tap the 4GHz signal out. |
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Geostationary Satellites - 3.6GHz to 4.2GHz sky survey - Nils, pjm Satellite RF Freq IF Freq Modulation Position MHz MHz characteristics =========================================================================== 40.5°e 3703.7875 1446.2125 Very strong PSK Express AM1 3947.500 1202.500 TT&C 3950.000 1250.000 Continuous carrier 33°e 3703.115 1446.885 Possible TT&C Intelsat 802 3738.100 1411.900 FM channel with data RHCP 3738.145 1411.855 FM channel with data 4099.750 1050.250 Strong PSK 26°e 4178.005 971.995 Continuous carrier Badr-C 25.5°e 3599.650 1550.350 PSK Inmarsat 3F5 3603.550 1546.450 PSK 3603.750 1546.250 PSK 3603.800 1546.200 PSK 3604.275 1545.725 PSK 3604.375 1545.625 PSK 3605.250 1544.750 PSK 3605.450 1544.550 PSK 3607.525 1542.475 Continuous carrier 3608.425 1541.575 20 PSK channels 3610.250 1539.750 PSK 3610.375 1539.625 PSK 3610.750 1539.250 PSK 1°w 3812.000R 1338.000 Frequency hopping modem Intelsat 10-02 3872.000R 1278.000 Continuous carrier 3947.500R 1202.500 TT&C 3952.500R 1197.500 TT&C 3938.100R 1211.900 Narrow PSK 4027.575R 1122.425 Narrow PSK 4009.565L 1140.435 Analogue phone channel 4009.655L 1140.345 Analogue phone channel paired with 4010.962 4009.700L 1140.300 Analogue phone channel paired with 4010.369 4009.745L 1140.255 Analogue phone channel 4009.790L 1140.210 Analogue phone channel 4009.832L 1140.168 Analogue phone channel 4010.015L 1139.985 Analogue phone channel 4010.150L 1139.850 Analogue phone channel 4010.195L 1139.805 Analogue phone channel 4010.330L 1139.670 Analogue phone channel 4010.369L 1139.631 Analogue phone channel paired with 4009.700 4010.375L 1139.625 Analogue phone channel 4010.690L 1139.310 Analogue phone channel 4010.827L 1139.173 Analogue phone channel 4010.874L 1139.126 Analogue phone channel 4010.962L 1139.038 Analogue phone channel paired with 4009.655 4011.189L 1138.811 Analogue phone channel 4011.233L 1138.767 Analogue phone channel 4011.278L 1138.722 Analogue phone channel 4011.369L 1138.631 Analogue phone channel 4011.413L 1138.587 Analogue phone channel 4011.459L 1138.541 Analogue phone channel 4011.503L 1138.497 Analogue phone channel 4011.594L 1138.406 Analogue phone channel 4011.638L 1138.362 Analogue phone channel 4011.685L 1138.315 Analogue phone channel 4011.907L 1138.093 Analogue phone channel 4012.269L 1137.731 Analogue phone channel 4012.360L 1137.640 Analogue phone channel 4012.447L 1137.553 Analogue phone channel 4012.629L 1137.371 Analogue phone channel 4012.717L 1137.283 Analogue phone channel 4012.896L 1137.104 Analogue phone channel 4012.985L 1137.015 Analogue phone channel 4013.124L 1136.876 Analogue phone channel 4013.210L 1136.790 Analogue phone channel 4013.303L 1136.697 Analogue phone channel 4013.437L 1136.563 Analogue phone channel 4013.480L 1136.520 Analogue phone channel 4013.572L 1136.428 Analogue phone channel 4013.617L 1136.383 Analogue phone channel 4013.750L 1136.250 Analogue phone channel 4013.799L 1136.201 Analogue phone channel 4013.842L 1136.158 Analogue phone channel 4013.884L 1136.116 Analogue phone channel 4013.935L 1136.065 Analogue phone channel 4014.000L 1136.000 Analogue phone channel(above) SCPC traffic at C-band on 1w LHCP. 5°w 3759.245R 1390.755 Narrow band PSK data Atlantic Bird 4016.140R 1133.860 Continuous carrier 4027.710R 1122.290 PSK 4028.060R 1121.940 Strong PSK 4199.500L 950.500 TT&C 8°w 3818.500 1331.500 Possible TT&C Telecom 2D 3892.510 1257.490 Possible TT&C 3905.075 1244.925 PSK 3905.250 1244.750 PSK 3941.750 1208.250 PSK 11°w 3700.000 1450.000 Continuous carrier Express A3 3775.000 1375.000 Continuous carrier 3800.000 1350.000 Continuous carrier 3941.750 1208.250 Very strong PSK 14°w 3758.270 1391.730 Narrow band PSK Express 4A 3758.330 1391.670 Slow rate FSK data 3759.250 1390.750 TT&C / Data 3800.010 1349.990 Continuous carrier 3950.675 1199.325 Data with two sidebands 15.5°w 3605.425 1544.575 Analogue phone channel (1535.425 return) Inmarsat 3F2 3605.450 1544.550 Analogue phone channel (1535.450 return) 3605.475 1544.525 Analogue phone channel (1535.475 return) 3605.500 1544.500 Analogue phone channel (1535.500 return) 3605.525 1544.475 Analogue phone channel (1535.525 return) 3608.450 1541.550 Analogue phone channel (1538.450 return) 3608.475 1541.525 Analogue phone channel (1538.475 return) 3609.875 1540.125 Analogue phone channel (1539.875 return) 3610.050 1539.950 Analogue phone channel (1540.050 return) 3610.975 1539.025 Analogue phone channel (1540.975 return) 3611.025 1538.975 Analogue phone channel (1541.025 return) 3611.200 1538.800 Analogue phone channel (1541.200 return) 3612.000 1538.000 Analogue phone channel (1542.000 return) Transponder RX band MHz TX band MHz Forward 6424.000 to 6454.000 1525.000 to 1559.000 Return 1626.500 to 1660.500 3600.000 to 3629.000 C to C 6432.300 to 6433.200 3607.300 to 3608.200 L to L 1640.850 to 1641.850 1539.350 to 1540.350 Nav (Egnos etc) 3629.400 to 3631.600 1574.400 to 1576.600 18°w 3947.500 1202.500 TT&C Intelsat 901 3950.000 1200.000 continuous carrier RHCP 3952.500 1197.500 TT&C 4065.075 1084.925 Radio Station Feeder (not 24h) LHCP 4194.175 955.825 Strong PSK 22°w 3873.000 1277.000 Strong PSK NSS 7 3943.275 1206.725 Strong PSK 24.5°w 3952.500 1197.500 TT&C Intelsat 905 3961.800 1188.200 Very strong PSK 27.5°w 3894.275 1255.725 Very Strong PSK Intelsat 907 3947.500 1202.500 TT&C RHCP 3952.500 1197.500 TT&C 3959.110 1190.890 Analogue phone circuit 3959.155 1190.845 Analogue phone circuit 3959.785 1190.215 Arabic Radio Station feeder 3959.875 1190.125 Analogue phone circuit 3959.920 1190.080 Analogue phone circuit 3959.650 1190.350 Analogue phone circuit 3960.370 1189.630 Analogue phone circuit 3960.595 1189.405 Analogue phone circuit 3960.865 1189.135 Analogue phone circuit 3960.945 1189.055 Analogue phone circuit 3961.085 1188.915 Analogue phone circuit 3961.270 1188.730 Analogue phone circuit 3961.360 1188.640 Analogue phone circuit 3961.405 1188.595 Analogue phone circuit 3961.585 1188.415 Analogue phone circuit 3961.810 1188.190 Very strong PSK 3961.945 1188.055 Analogue phone circuit 3962.080 1187.920 Analogue phone circuit with periodic ASCII data 3962.620 1187.380 Analogue phone circuit 3962.710 1187.290 Analogue phone circuit 3962.940 1187.060 Analogue phone circuit 3963.295 1186.705 Analogue phone circuit 3963.465 1186.535 Analogue phone circuit 3963.520 1186.480 Analogue phone circuit 3964.005 1185.995 Analogue phone circuit 3986.700 1163.300 Radio Station Feeder 31.5°w 3650.475 1499.525 Very strong PSK Intelsat 801 3650.550 1499.450 Very strong PSK RHCP 3650.775 1499.225 PSK 3651.425 1498.575 PSK 3651.575 1498.425 PSK 3651.600 1498.400 PSK 3723.875 1426.125 Cluster of 12 narrow band PSK 3789.000 1361.000 Continuous carrier 3789.305 1360.695 Analogue phone circuit 3789.425 1360.575 Analogue phone circuit 3789.545 1360.455 Analogue phone circuit 3789.6625 1360.3375 Analogue phone circuit 3790.025 1359.975 Analogue phone circuit 3790.980 1359.020 Analogue phone circuit 3795.120 1354.880 Analogue phone circuit 3795.180 1354.8125 Analogue phone circuit 3795.420 1354.575 Analogue phone circuit 3795.540 1354.460 Analogue phone circuit 3795.6625 1354.3375 Analogue phone circuit 3796.800 1353.200 Analogue phone circuit 3796.980 1353.020 Analogue phone circuit 3798.000 1352.000 Continuous carrier 3807.120 1342.880 Analogue phone circuit 3807.182 1342.818 Analogue phone circuit 3807.205 1342.795 Analogue phone circuit 3807.360 1342.640 Analogue phone circuit 3807.450 1342.550 Analogue phone circuit 3807.750 1342.250 Analogue phone circuit 3807.870 1342.130 Analogue phone circuit 3807.902 1342.098 Analogue phone circuit 3807.925 1342.075 Analogue phone circuit 3808.084 1341.916 Analogue phone circuit 3808.175 1341.825 Analogue phone circuit 3808.320 1341.680 Analogue phone circuit 3808.439 1341.561 Analogue phone circuit 3815.790 1334.210 African Radio Feeder with stereo pilots 3947.500 1202.500 TT&C 3950.000 1200.000 Tracking Beacon 3952.500 1197.500 TT&C LHCP 3899.967 1250.033 Continuous carrier 4117.100 1032.900 PSK 34.0°w 3945.526 1204.474 TT&C 1000bps DBPSK Marisat F2 Highly inclined
(above) Marisat-F2 TT&C at 3945.526 34.5°w RHCP 3932.825 1217.175 PSK Intelsat 903 3947.500 1202.500 TT&C 3952.500 1197.500 TT&C 3669.275 1480.725 PSK 4104.925 1045.075 PSK LHCP 3695.500 1454.500 QRT? Radio Station Feeder - Danish Radio Faro/Greenland (Tnx Brian-DK) 3698.000 1452.000 QRT? Radio Station Feeder (Norway) 3701.2525 1448.7475 Carrier with flutter 3703.000 1447.000 QRT? Radio Station Feeder - Danish Radio Programme 1 (Tnx Brian-DK)
(above) Spectrum of Danmarks Radio feeder via 34.5 west at 3703.000 LHCP 37.5°w Hor 4008.020 1141.980 French station Tropical music (Tnx to LR) 40.5°w RHCP 3628.730 1521.270 Very strong PSK NSS 806 3629.360 1520.640 Very strong PSK 3725.000 1425.000 Continuous carrier 3861.500 1288.500 Continuous carrier 3947.500 1202.500 TT&C 3952.500 1197.500 TT&C 43°w 3703.000 1447.000 Possible TT&C Carrier + 2 sidebands Panamsat 3R 3719.400 1430.600 Strong PSK 3991.900 1158.100 PSK 4199.500 950.500 Possible TT&C Carrier + 2 sidebands 45°w 3801.450 1348.550 Continuous Carrier Panamsat 1R 4126.300 1023.700 Very strong PSK 4198.490 951.510 Possible TT&C Carrier + 2 sidebands 4198.990 951.010 Possible TT&C Carrier + 2 sidebands 4199.510 950.490 Continuous Carrier 50°w RHCP 3952.000 1198.000 TT&C Intelsat 705 3950.000 1200.000 Continuous carrier 3947.500 1202.500 TT&C 109.2°W Hor 3897.915 1252.085 Unknown FM station from San Diego Cal. Satmex 6 3897.120 1252.880 Unknown FM station (Tnx to LR) 3891.330 1258.670 Unknown Jazz station Ver 3899.730 1250.270 La voz de Guayana. Estado Bolivar ( Bolivar State) 89.7 FM Spanish
Some general information about Intelsat TT&C tracking beacons: Intelsat Satellite Designation Frequency (MHz) IF (MHz) VII, VIIA, VIII, VIIIA and IX 3,947.500 1202.500 3,948.000 1202.000 Note: only two of these may 3,952.000 1198.000 be active at any one time 3,952.500 1197.500 3,950.000 1200.000 continuous carrier Panamsat satellites use the following c-band frequencies for tt&c / beacons Frequency (MHz) IF (MHz) 4198.500 951.500 4199.000 951.000 4199.500 950.500 More to come! Tnx to c.h. for this great info!
High Earth Orbit Satellites - 3.6GHz to 4.2GHz sky survey - pjm Satellite RF Freq IF Freq Modulation
MHz MHz characteristics
=========================================================================== Meridian 3 3691.000 1459.000 2MHz wide lump 3645.000 1505.000 500MHz wide lump 3625.000 1525.000 PSK with sidebands, strong 3610.025 1539.975 50 bps FSK 3605.000 1545.000 400KHz wide noise 'lump' possible TPX loop Molniya 3-53 3857.555 1292.445 PSK HEO 3758.900 1391.100 Very strong PSK (periodic Doppler correction on downlink) USSR Apogee 3765.640 1384.360 DSSS 3770.445 1379.555 DSSS 3870.425 1279.575 DSSS 3882.925 1267.075 DSSS 3657.610 1492.390 PSK Canada Apogee 3680.765 1469.235 PSK (New 8/7/2006) 3758.875 1391.125 PSK 3760.950 1389.050 PSK 3761.650 1388.350 PSK 3764.650 1385.350 PSK (New 8/7/2006) 3857.520 1292.490 PSK 3869.720 1280.280 PSK Molniya 3-5? 3759.030 1390.970 PSK HEO 3760.855 1389.145 PSK Canada Apogee 3761.550 1388.450 PSK 3764.600 1385.400 PSK with regular framing Transponder frequencies for Molniya-1 C-Band (obtained from observations) TPX-1 3700.000 to 3750.000 50MHz b/w TPX-2 3775.000 to 3825.000 50MHz b/w TPX-3 3850.000 to 3900.000 50MHz b/w Transponder frequencies for Molniya-3 C-Band (obtained from observations) TPX-1 3650.000 to 3700.000 50MHz b/w TPX-2 3750.000 to 3800.000 50MHz b/w TPX-3 3850.000 to 3900.000 50MHz b/w
 3758.900 from Molniya 3-53 HEO |
 3760.770 from Molniya 3-53 HEO |