Changes in Inmarsat Frequencies

 On both the 25E and 54W satellites the 10500 bps channels were changed from around the 1546 Mhz to around 1545.4Mhz

 

With SDRReceiver this also meant changing the bandwidth setting of main vfo1 to 768000 from 384000.

Theses are the new SdrReceiver .ini files for both satellites

25E

sample_rate=1536000
center_frequency=1545600000
zmq_address=tcp://*:6003

#auto_start=1
#auto_start_tuner_idx=0

#remote_rtl=127.0.0.1:1234

#valid tuner gains r82xx_gains[] = { 0, 9, 14, 27, 37, 77, 87, 125, 144, 157, 166, 197, 207, 229, 254, 280, 297, 328, 338, 364, 372, 386, 402, 421, 434, 439, 445, 480, 496 };
tuner_gain=496
correct_dc_bias=1
mix_offset=0

 

[main_vfos]
size=2
1\frequency=1545116000
1\out_rate=768000
2\frequency=1546096000
2\out_rate=192000

[vfos]
size=6
1\frequency=1545116000
1\gain=5
1\data_rate=600
1\fiter_bandwidth=0
1\topic=VFO02
2\frequency=1545121000
2\gain=5
2\data_rate=600
2\fiter_bandwidth=0
2\topic=VFO03
3\frequency=1545125000
3\gain=5
3\data_rate=1200
3\fiter_bandwidth=0
3\topic=VFO04
4\frequency=1545131000
4\gain=5
4\data_rate=600
4\fiter_bandwidth=0
4\topic=VFO05
5\frequency=1545308000
5\gain=5
5\data_rate=10500
5\fiter_bandwidth=0
5\topic=VFO07
6\frequency=1545321000
6\gain=5
6\data_rate=10500
6\fiter_bandwidth=0
6\topic=VFO08

Exact frequencies taken from the control channel (1545.115MHz) - October 2026

2 0x40 0xAE 0x4F 0x15 0x90 0xDD 0x51 0x01 0x36 0xE0 P_R_channel_control_ISU GES = 90 Pd = 1545.120MHz at 600bps
1 0x40 0x43 0xC6 0xF8 0x90 0xDF 0x51 0x11 0x36 0xE2 P_R_channel_control_ISU GES = 90 Pd = 1545.125MHz at 1200bps
3 0x40 0x06 0xA0 0xC1 0x90 0xDE 0x51 0x01 0x36 0xE4 P_R_channel_control_ISU GES = 90 Pd = 1545.130MHz at 600bps
5 0x40 0x49 0x1D 0x99 0x90 0xD4 0x51 0x66 0x37 0x2E P_R_channel_control_ISU GES = 90 Pd = 1545.315MHz at 10500bps
5 0x40 0x48 0x45 0x61 0x90 0xD6 0x51 0x66 0x37 0x33 P_R_channel_control_ISU GES = 90 Pd = 1545.328MHz at 10500bps

54W

sample_rate=1536000
center_frequency=1545600000
zmq_address=tcp://*:6004

#auto_start=1
#auto_start_tuner_idx=0

#remote_rtl=127.0.0.1:1234

#valid tuner gains r82xx_gains[] = { 0, 9, 14, 27, 37, 77, 87, 125, 144, 157, 166, 197, 207, 229, 254, 280, 297, 328, 338, 364, 372, 386, 402, 421, 434, 439, 445, 480, 496 };
tuner_gain=496
correct_dc_bias=1
mix_offset=0

 

[main_vfos]
size=2
1\frequency=1545116000
1\out_rate=768000
2\frequency=1546096000
2\out_rate=192000

 

[vfos]
size=8
1\frequency=1545014000
1\gain=20
1\data_rate=600
1\fiter_bandwidth=0
1\topic=VFO41
2\frequency=1545024000
2\gain=20
2\data_rate=600
2\fiter_bandwidth=0
2\topic=VFO42
3\frequency=1545029000
3\gain=20
3\data_rate=600
3\fiter_bandwidth=0
3\topic=VFO43
4\frequency=1545034000
4\gain=20
4\data_rate=600
4\fiter_bandwidth=0
4\topic=VFO44
5\frequency=1545039000
5\gain=20
5\data_rate=600
5\fiter_bandwidth=0
5\topic=VFO45
6\frequency=1545194000
6\gain=20
6\data_rate=600
6\fiter_bandwidth=0
6\topic=VFO46
7\frequency=1545345000
7\gain=20
7\data_rate=10500
7\fiter_bandwidth=0
7\topic=VFO47
8\frequency=1545360000
8\gain=20
8\data_rate=10500
8\fiter_bandwidth=0
8\topic=VFO48

Exact Frequencies for 54W:

GES 43 - Control 1545.015Mhz

P_R_channel_control_ISU GES = 43 Pd = 1545.030MHz at 600bps

P_R_channel_control_ISU GES = 43 Pd = 1545.040MHz at 600bps

P_R_channel_control_ISU GES = 43 Pd = 1545.368MHz at 10500bps

GES 44 Control 1545.195MHz

P_R_channel_control_ISU GES = 44 Pd = 1545.025MHz at 600bps

P_R_channel_control_ISU GES = 44 Pd = 1545.035MHz at 600bps

P_R_channel_control_ISU GES = 44 Pd = 1545.352MHz at 10500bps

Note, there are no 1200bps channels on 54W